4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23 * Copyright (c) 2011, 2018 by Delphix. All rights reserved.
24 * Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
25 * Copyright (c) 2014 Integros [integros.com]
28 #include <sys/zfs_context.h>
30 #include <sys/dmu_tx.h>
31 #include <sys/space_map.h>
32 #include <sys/metaslab_impl.h>
33 #include <sys/vdev_impl.h>
35 #include <sys/spa_impl.h>
36 #include <sys/zfeature.h>
37 #include <sys/vdev_indirect_mapping.h>
40 #define GANG_ALLOCATION(flags) \
41 ((flags) & (METASLAB_GANG_CHILD | METASLAB_GANG_HEADER))
43 uint64_t metaslab_aliquot
= 512ULL << 10;
44 uint64_t metaslab_force_ganging
= SPA_MAXBLOCKSIZE
+ 1; /* force gang blocks */
47 * Since we can touch multiple metaslabs (and their respective space maps)
48 * with each transaction group, we benefit from having a smaller space map
49 * block size since it allows us to issue more I/O operations scattered
52 int zfs_metaslab_sm_blksz
= (1 << 12);
55 * The in-core space map representation is more compact than its on-disk form.
56 * The zfs_condense_pct determines how much more compact the in-core
57 * space map representation must be before we compact it on-disk.
58 * Values should be greater than or equal to 100.
60 int zfs_condense_pct
= 200;
63 * Condensing a metaslab is not guaranteed to actually reduce the amount of
64 * space used on disk. In particular, a space map uses data in increments of
65 * MAX(1 << ashift, space_map_blksize), so a metaslab might use the
66 * same number of blocks after condensing. Since the goal of condensing is to
67 * reduce the number of IOPs required to read the space map, we only want to
68 * condense when we can be sure we will reduce the number of blocks used by the
69 * space map. Unfortunately, we cannot precisely compute whether or not this is
70 * the case in metaslab_should_condense since we are holding ms_lock. Instead,
71 * we apply the following heuristic: do not condense a spacemap unless the
72 * uncondensed size consumes greater than zfs_metaslab_condense_block_threshold
75 int zfs_metaslab_condense_block_threshold
= 4;
78 * The zfs_mg_noalloc_threshold defines which metaslab groups should
79 * be eligible for allocation. The value is defined as a percentage of
80 * free space. Metaslab groups that have more free space than
81 * zfs_mg_noalloc_threshold are always eligible for allocations. Once
82 * a metaslab group's free space is less than or equal to the
83 * zfs_mg_noalloc_threshold the allocator will avoid allocating to that
84 * group unless all groups in the pool have reached zfs_mg_noalloc_threshold.
85 * Once all groups in the pool reach zfs_mg_noalloc_threshold then all
86 * groups are allowed to accept allocations. Gang blocks are always
87 * eligible to allocate on any metaslab group. The default value of 0 means
88 * no metaslab group will be excluded based on this criterion.
90 int zfs_mg_noalloc_threshold
= 0;
93 * Metaslab groups are considered eligible for allocations if their
94 * fragmenation metric (measured as a percentage) is less than or equal to
95 * zfs_mg_fragmentation_threshold. If a metaslab group exceeds this threshold
96 * then it will be skipped unless all metaslab groups within the metaslab
97 * class have also crossed this threshold.
99 int zfs_mg_fragmentation_threshold
= 85;
102 * Allow metaslabs to keep their active state as long as their fragmentation
103 * percentage is less than or equal to zfs_metaslab_fragmentation_threshold. An
104 * active metaslab that exceeds this threshold will no longer keep its active
105 * status allowing better metaslabs to be selected.
107 int zfs_metaslab_fragmentation_threshold
= 70;
110 * When set will load all metaslabs when pool is first opened.
112 int metaslab_debug_load
= 0;
115 * When set will prevent metaslabs from being unloaded.
117 int metaslab_debug_unload
= 0;
120 * Minimum size which forces the dynamic allocator to change
121 * it's allocation strategy. Once the space map cannot satisfy
122 * an allocation of this size then it switches to using more
123 * aggressive strategy (i.e search by size rather than offset).
125 uint64_t metaslab_df_alloc_threshold
= SPA_OLD_MAXBLOCKSIZE
;
128 * The minimum free space, in percent, which must be available
129 * in a space map to continue allocations in a first-fit fashion.
130 * Once the space map's free space drops below this level we dynamically
131 * switch to using best-fit allocations.
133 int metaslab_df_free_pct
= 4;
136 * A metaslab is considered "free" if it contains a contiguous
137 * segment which is greater than metaslab_min_alloc_size.
139 uint64_t metaslab_min_alloc_size
= DMU_MAX_ACCESS
;
142 * Percentage of all cpus that can be used by the metaslab taskq.
144 int metaslab_load_pct
= 50;
147 * Determines how many txgs a metaslab may remain loaded without having any
148 * allocations from it. As long as a metaslab continues to be used we will
151 int metaslab_unload_delay
= TXG_SIZE
* 2;
154 * Max number of metaslabs per group to preload.
156 int metaslab_preload_limit
= SPA_DVAS_PER_BP
;
159 * Enable/disable preloading of metaslab.
161 boolean_t metaslab_preload_enabled
= B_TRUE
;
164 * Enable/disable fragmentation weighting on metaslabs.
166 boolean_t metaslab_fragmentation_factor_enabled
= B_TRUE
;
169 * Enable/disable lba weighting (i.e. outer tracks are given preference).
171 boolean_t metaslab_lba_weighting_enabled
= B_TRUE
;
174 * Enable/disable metaslab group biasing.
176 boolean_t metaslab_bias_enabled
= B_TRUE
;
179 * Enable/disable remapping of indirect DVAs to their concrete vdevs.
181 boolean_t zfs_remap_blkptr_enable
= B_TRUE
;
184 * Enable/disable segment-based metaslab selection.
186 boolean_t zfs_metaslab_segment_weight_enabled
= B_TRUE
;
189 * When using segment-based metaslab selection, we will continue
190 * allocating from the active metaslab until we have exhausted
191 * zfs_metaslab_switch_threshold of its buckets.
193 int zfs_metaslab_switch_threshold
= 2;
196 * Internal switch to enable/disable the metaslab allocation tracing
199 boolean_t metaslab_trace_enabled
= B_TRUE
;
202 * Maximum entries that the metaslab allocation tracing facility will keep
203 * in a given list when running in non-debug mode. We limit the number
204 * of entries in non-debug mode to prevent us from using up too much memory.
205 * The limit should be sufficiently large that we don't expect any allocation
206 * to every exceed this value. In debug mode, the system will panic if this
207 * limit is ever reached allowing for further investigation.
209 uint64_t metaslab_trace_max_entries
= 5000;
211 static uint64_t metaslab_weight(metaslab_t
*);
212 static void metaslab_set_fragmentation(metaslab_t
*);
213 static void metaslab_free_impl(vdev_t
*, uint64_t, uint64_t, boolean_t
);
214 static void metaslab_check_free_impl(vdev_t
*, uint64_t, uint64_t);
215 static void metaslab_passivate(metaslab_t
*msp
, uint64_t weight
);
216 static uint64_t metaslab_weight_from_range_tree(metaslab_t
*msp
);
218 kmem_cache_t
*metaslab_alloc_trace_cache
;
221 * ==========================================================================
223 * ==========================================================================
226 metaslab_class_create(spa_t
*spa
, metaslab_ops_t
*ops
)
228 metaslab_class_t
*mc
;
230 mc
= kmem_zalloc(sizeof (metaslab_class_t
), KM_SLEEP
);
235 mutex_init(&mc
->mc_lock
, NULL
, MUTEX_DEFAULT
, NULL
);
236 mc
->mc_alloc_slots
= kmem_zalloc(spa
->spa_alloc_count
*
237 sizeof (refcount_t
), KM_SLEEP
);
238 mc
->mc_alloc_max_slots
= kmem_zalloc(spa
->spa_alloc_count
*
239 sizeof (uint64_t), KM_SLEEP
);
240 for (int i
= 0; i
< spa
->spa_alloc_count
; i
++)
241 refcount_create_tracked(&mc
->mc_alloc_slots
[i
]);
247 metaslab_class_destroy(metaslab_class_t
*mc
)
249 ASSERT(mc
->mc_rotor
== NULL
);
250 ASSERT(mc
->mc_alloc
== 0);
251 ASSERT(mc
->mc_deferred
== 0);
252 ASSERT(mc
->mc_space
== 0);
253 ASSERT(mc
->mc_dspace
== 0);
255 for (int i
= 0; i
< mc
->mc_spa
->spa_alloc_count
; i
++)
256 refcount_destroy(&mc
->mc_alloc_slots
[i
]);
257 kmem_free(mc
->mc_alloc_slots
, mc
->mc_spa
->spa_alloc_count
*
258 sizeof (refcount_t
));
259 kmem_free(mc
->mc_alloc_max_slots
, mc
->mc_spa
->spa_alloc_count
*
261 mutex_destroy(&mc
->mc_lock
);
262 kmem_free(mc
, sizeof (metaslab_class_t
));
266 metaslab_class_validate(metaslab_class_t
*mc
)
268 metaslab_group_t
*mg
;
272 * Must hold one of the spa_config locks.
274 ASSERT(spa_config_held(mc
->mc_spa
, SCL_ALL
, RW_READER
) ||
275 spa_config_held(mc
->mc_spa
, SCL_ALL
, RW_WRITER
));
277 if ((mg
= mc
->mc_rotor
) == NULL
)
282 ASSERT(vd
->vdev_mg
!= NULL
);
283 ASSERT3P(vd
->vdev_top
, ==, vd
);
284 ASSERT3P(mg
->mg_class
, ==, mc
);
285 ASSERT3P(vd
->vdev_ops
, !=, &vdev_hole_ops
);
286 } while ((mg
= mg
->mg_next
) != mc
->mc_rotor
);
292 metaslab_class_space_update(metaslab_class_t
*mc
, int64_t alloc_delta
,
293 int64_t defer_delta
, int64_t space_delta
, int64_t dspace_delta
)
295 atomic_add_64(&mc
->mc_alloc
, alloc_delta
);
296 atomic_add_64(&mc
->mc_deferred
, defer_delta
);
297 atomic_add_64(&mc
->mc_space
, space_delta
);
298 atomic_add_64(&mc
->mc_dspace
, dspace_delta
);
302 metaslab_class_get_alloc(metaslab_class_t
*mc
)
304 return (mc
->mc_alloc
);
308 metaslab_class_get_deferred(metaslab_class_t
*mc
)
310 return (mc
->mc_deferred
);
314 metaslab_class_get_space(metaslab_class_t
*mc
)
316 return (mc
->mc_space
);
320 metaslab_class_get_dspace(metaslab_class_t
*mc
)
322 return (spa_deflate(mc
->mc_spa
) ? mc
->mc_dspace
: mc
->mc_space
);
326 metaslab_class_histogram_verify(metaslab_class_t
*mc
)
328 vdev_t
*rvd
= mc
->mc_spa
->spa_root_vdev
;
332 if ((zfs_flags
& ZFS_DEBUG_HISTOGRAM_VERIFY
) == 0)
335 mc_hist
= kmem_zalloc(sizeof (uint64_t) * RANGE_TREE_HISTOGRAM_SIZE
,
338 for (int c
= 0; c
< rvd
->vdev_children
; c
++) {
339 vdev_t
*tvd
= rvd
->vdev_child
[c
];
340 metaslab_group_t
*mg
= tvd
->vdev_mg
;
343 * Skip any holes, uninitialized top-levels, or
344 * vdevs that are not in this metalab class.
346 if (!vdev_is_concrete(tvd
) || tvd
->vdev_ms_shift
== 0 ||
347 mg
->mg_class
!= mc
) {
351 for (i
= 0; i
< RANGE_TREE_HISTOGRAM_SIZE
; i
++)
352 mc_hist
[i
] += mg
->mg_histogram
[i
];
355 for (i
= 0; i
< RANGE_TREE_HISTOGRAM_SIZE
; i
++)
356 VERIFY3U(mc_hist
[i
], ==, mc
->mc_histogram
[i
]);
358 kmem_free(mc_hist
, sizeof (uint64_t) * RANGE_TREE_HISTOGRAM_SIZE
);
362 * Calculate the metaslab class's fragmentation metric. The metric
363 * is weighted based on the space contribution of each metaslab group.
364 * The return value will be a number between 0 and 100 (inclusive), or
365 * ZFS_FRAG_INVALID if the metric has not been set. See comment above the
366 * zfs_frag_table for more information about the metric.
369 metaslab_class_fragmentation(metaslab_class_t
*mc
)
371 vdev_t
*rvd
= mc
->mc_spa
->spa_root_vdev
;
372 uint64_t fragmentation
= 0;
374 spa_config_enter(mc
->mc_spa
, SCL_VDEV
, FTAG
, RW_READER
);
376 for (int c
= 0; c
< rvd
->vdev_children
; c
++) {
377 vdev_t
*tvd
= rvd
->vdev_child
[c
];
378 metaslab_group_t
*mg
= tvd
->vdev_mg
;
381 * Skip any holes, uninitialized top-levels,
382 * or vdevs that are not in this metalab class.
384 if (!vdev_is_concrete(tvd
) || tvd
->vdev_ms_shift
== 0 ||
385 mg
->mg_class
!= mc
) {
390 * If a metaslab group does not contain a fragmentation
391 * metric then just bail out.
393 if (mg
->mg_fragmentation
== ZFS_FRAG_INVALID
) {
394 spa_config_exit(mc
->mc_spa
, SCL_VDEV
, FTAG
);
395 return (ZFS_FRAG_INVALID
);
399 * Determine how much this metaslab_group is contributing
400 * to the overall pool fragmentation metric.
402 fragmentation
+= mg
->mg_fragmentation
*
403 metaslab_group_get_space(mg
);
405 fragmentation
/= metaslab_class_get_space(mc
);
407 ASSERT3U(fragmentation
, <=, 100);
408 spa_config_exit(mc
->mc_spa
, SCL_VDEV
, FTAG
);
409 return (fragmentation
);
413 * Calculate the amount of expandable space that is available in
414 * this metaslab class. If a device is expanded then its expandable
415 * space will be the amount of allocatable space that is currently not
416 * part of this metaslab class.
419 metaslab_class_expandable_space(metaslab_class_t
*mc
)
421 vdev_t
*rvd
= mc
->mc_spa
->spa_root_vdev
;
424 spa_config_enter(mc
->mc_spa
, SCL_VDEV
, FTAG
, RW_READER
);
425 for (int c
= 0; c
< rvd
->vdev_children
; c
++) {
427 vdev_t
*tvd
= rvd
->vdev_child
[c
];
428 metaslab_group_t
*mg
= tvd
->vdev_mg
;
430 if (!vdev_is_concrete(tvd
) || tvd
->vdev_ms_shift
== 0 ||
431 mg
->mg_class
!= mc
) {
436 * Calculate if we have enough space to add additional
437 * metaslabs. We report the expandable space in terms
438 * of the metaslab size since that's the unit of expansion.
439 * Adjust by efi system partition size.
441 tspace
= tvd
->vdev_max_asize
- tvd
->vdev_asize
;
442 if (tspace
> mc
->mc_spa
->spa_bootsize
) {
443 tspace
-= mc
->mc_spa
->spa_bootsize
;
445 space
+= P2ALIGN(tspace
, 1ULL << tvd
->vdev_ms_shift
);
447 spa_config_exit(mc
->mc_spa
, SCL_VDEV
, FTAG
);
452 metaslab_compare(const void *x1
, const void *x2
)
454 const metaslab_t
*m1
= x1
;
455 const metaslab_t
*m2
= x2
;
459 if (m1
->ms_allocator
!= -1 && m1
->ms_primary
)
461 else if (m1
->ms_allocator
!= -1 && !m1
->ms_primary
)
463 if (m2
->ms_allocator
!= -1 && m2
->ms_primary
)
465 else if (m2
->ms_allocator
!= -1 && !m2
->ms_primary
)
469 * Sort inactive metaslabs first, then primaries, then secondaries. When
470 * selecting a metaslab to allocate from, an allocator first tries its
471 * primary, then secondary active metaslab. If it doesn't have active
472 * metaslabs, or can't allocate from them, it searches for an inactive
473 * metaslab to activate. If it can't find a suitable one, it will steal
474 * a primary or secondary metaslab from another allocator.
481 if (m1
->ms_weight
< m2
->ms_weight
)
483 if (m1
->ms_weight
> m2
->ms_weight
)
487 * If the weights are identical, use the offset to force uniqueness.
489 if (m1
->ms_start
< m2
->ms_start
)
491 if (m1
->ms_start
> m2
->ms_start
)
494 ASSERT3P(m1
, ==, m2
);
500 * Verify that the space accounting on disk matches the in-core range_trees.
503 metaslab_verify_space(metaslab_t
*msp
, uint64_t txg
)
505 spa_t
*spa
= msp
->ms_group
->mg_vd
->vdev_spa
;
506 uint64_t allocated
= 0;
507 uint64_t sm_free_space
, msp_free_space
;
509 ASSERT(MUTEX_HELD(&msp
->ms_lock
));
511 if ((zfs_flags
& ZFS_DEBUG_METASLAB_VERIFY
) == 0)
515 * We can only verify the metaslab space when we're called
516 * from syncing context with a loaded metaslab that has an allocated
517 * space map. Calling this in non-syncing context does not
518 * provide a consistent view of the metaslab since we're performing
519 * allocations in the future.
521 if (txg
!= spa_syncing_txg(spa
) || msp
->ms_sm
== NULL
||
525 sm_free_space
= msp
->ms_size
- space_map_allocated(msp
->ms_sm
) -
526 space_map_alloc_delta(msp
->ms_sm
);
529 * Account for future allocations since we would have already
530 * deducted that space from the ms_freetree.
532 for (int t
= 0; t
< TXG_CONCURRENT_STATES
; t
++) {
534 range_tree_space(msp
->ms_allocating
[(txg
+ t
) & TXG_MASK
]);
537 msp_free_space
= range_tree_space(msp
->ms_allocatable
) + allocated
+
538 msp
->ms_deferspace
+ range_tree_space(msp
->ms_freed
);
540 VERIFY3U(sm_free_space
, ==, msp_free_space
);
544 * ==========================================================================
546 * ==========================================================================
549 * Update the allocatable flag and the metaslab group's capacity.
550 * The allocatable flag is set to true if the capacity is below
551 * the zfs_mg_noalloc_threshold or has a fragmentation value that is
552 * greater than zfs_mg_fragmentation_threshold. If a metaslab group
553 * transitions from allocatable to non-allocatable or vice versa then the
554 * metaslab group's class is updated to reflect the transition.
557 metaslab_group_alloc_update(metaslab_group_t
*mg
)
559 vdev_t
*vd
= mg
->mg_vd
;
560 metaslab_class_t
*mc
= mg
->mg_class
;
561 vdev_stat_t
*vs
= &vd
->vdev_stat
;
562 boolean_t was_allocatable
;
563 boolean_t was_initialized
;
565 ASSERT(vd
== vd
->vdev_top
);
566 ASSERT3U(spa_config_held(mc
->mc_spa
, SCL_ALLOC
, RW_READER
), ==,
569 mutex_enter(&mg
->mg_lock
);
570 was_allocatable
= mg
->mg_allocatable
;
571 was_initialized
= mg
->mg_initialized
;
573 mg
->mg_free_capacity
= ((vs
->vs_space
- vs
->vs_alloc
) * 100) /
576 mutex_enter(&mc
->mc_lock
);
579 * If the metaslab group was just added then it won't
580 * have any space until we finish syncing out this txg.
581 * At that point we will consider it initialized and available
582 * for allocations. We also don't consider non-activated
583 * metaslab groups (e.g. vdevs that are in the middle of being removed)
584 * to be initialized, because they can't be used for allocation.
586 mg
->mg_initialized
= metaslab_group_initialized(mg
);
587 if (!was_initialized
&& mg
->mg_initialized
) {
589 } else if (was_initialized
&& !mg
->mg_initialized
) {
590 ASSERT3U(mc
->mc_groups
, >, 0);
593 if (mg
->mg_initialized
)
594 mg
->mg_no_free_space
= B_FALSE
;
597 * A metaslab group is considered allocatable if it has plenty
598 * of free space or is not heavily fragmented. We only take
599 * fragmentation into account if the metaslab group has a valid
600 * fragmentation metric (i.e. a value between 0 and 100).
602 mg
->mg_allocatable
= (mg
->mg_activation_count
> 0 &&
603 mg
->mg_free_capacity
> zfs_mg_noalloc_threshold
&&
604 (mg
->mg_fragmentation
== ZFS_FRAG_INVALID
||
605 mg
->mg_fragmentation
<= zfs_mg_fragmentation_threshold
));
608 * The mc_alloc_groups maintains a count of the number of
609 * groups in this metaslab class that are still above the
610 * zfs_mg_noalloc_threshold. This is used by the allocating
611 * threads to determine if they should avoid allocations to
612 * a given group. The allocator will avoid allocations to a group
613 * if that group has reached or is below the zfs_mg_noalloc_threshold
614 * and there are still other groups that are above the threshold.
615 * When a group transitions from allocatable to non-allocatable or
616 * vice versa we update the metaslab class to reflect that change.
617 * When the mc_alloc_groups value drops to 0 that means that all
618 * groups have reached the zfs_mg_noalloc_threshold making all groups
619 * eligible for allocations. This effectively means that all devices
620 * are balanced again.
622 if (was_allocatable
&& !mg
->mg_allocatable
)
623 mc
->mc_alloc_groups
--;
624 else if (!was_allocatable
&& mg
->mg_allocatable
)
625 mc
->mc_alloc_groups
++;
626 mutex_exit(&mc
->mc_lock
);
628 mutex_exit(&mg
->mg_lock
);
632 metaslab_group_create(metaslab_class_t
*mc
, vdev_t
*vd
, int allocators
)
634 metaslab_group_t
*mg
;
636 mg
= kmem_zalloc(sizeof (metaslab_group_t
), KM_SLEEP
);
637 mutex_init(&mg
->mg_lock
, NULL
, MUTEX_DEFAULT
, NULL
);
638 mg
->mg_primaries
= kmem_zalloc(allocators
* sizeof (metaslab_t
*),
640 mg
->mg_secondaries
= kmem_zalloc(allocators
* sizeof (metaslab_t
*),
642 avl_create(&mg
->mg_metaslab_tree
, metaslab_compare
,
643 sizeof (metaslab_t
), offsetof(struct metaslab
, ms_group_node
));
646 mg
->mg_activation_count
= 0;
647 mg
->mg_initialized
= B_FALSE
;
648 mg
->mg_no_free_space
= B_TRUE
;
649 mg
->mg_allocators
= allocators
;
651 mg
->mg_alloc_queue_depth
= kmem_zalloc(allocators
* sizeof (refcount_t
),
653 mg
->mg_cur_max_alloc_queue_depth
= kmem_zalloc(allocators
*
654 sizeof (uint64_t), KM_SLEEP
);
655 for (int i
= 0; i
< allocators
; i
++) {
656 refcount_create_tracked(&mg
->mg_alloc_queue_depth
[i
]);
657 mg
->mg_cur_max_alloc_queue_depth
[i
] = 0;
660 mg
->mg_taskq
= taskq_create("metaslab_group_taskq", metaslab_load_pct
,
661 minclsyspri
, 10, INT_MAX
, TASKQ_THREADS_CPU_PCT
);
667 metaslab_group_destroy(metaslab_group_t
*mg
)
669 ASSERT(mg
->mg_prev
== NULL
);
670 ASSERT(mg
->mg_next
== NULL
);
672 * We may have gone below zero with the activation count
673 * either because we never activated in the first place or
674 * because we're done, and possibly removing the vdev.
676 ASSERT(mg
->mg_activation_count
<= 0);
678 taskq_destroy(mg
->mg_taskq
);
679 avl_destroy(&mg
->mg_metaslab_tree
);
680 kmem_free(mg
->mg_primaries
, mg
->mg_allocators
* sizeof (metaslab_t
*));
681 kmem_free(mg
->mg_secondaries
, mg
->mg_allocators
*
682 sizeof (metaslab_t
*));
683 mutex_destroy(&mg
->mg_lock
);
685 for (int i
= 0; i
< mg
->mg_allocators
; i
++) {
686 refcount_destroy(&mg
->mg_alloc_queue_depth
[i
]);
687 mg
->mg_cur_max_alloc_queue_depth
[i
] = 0;
689 kmem_free(mg
->mg_alloc_queue_depth
, mg
->mg_allocators
*
690 sizeof (refcount_t
));
691 kmem_free(mg
->mg_cur_max_alloc_queue_depth
, mg
->mg_allocators
*
694 kmem_free(mg
, sizeof (metaslab_group_t
));
698 metaslab_group_activate(metaslab_group_t
*mg
)
700 metaslab_class_t
*mc
= mg
->mg_class
;
701 metaslab_group_t
*mgprev
, *mgnext
;
703 ASSERT3U(spa_config_held(mc
->mc_spa
, SCL_ALLOC
, RW_WRITER
), !=, 0);
705 ASSERT(mc
->mc_rotor
!= mg
);
706 ASSERT(mg
->mg_prev
== NULL
);
707 ASSERT(mg
->mg_next
== NULL
);
708 ASSERT(mg
->mg_activation_count
<= 0);
710 if (++mg
->mg_activation_count
<= 0)
713 mg
->mg_aliquot
= metaslab_aliquot
* MAX(1, mg
->mg_vd
->vdev_children
);
714 metaslab_group_alloc_update(mg
);
716 if ((mgprev
= mc
->mc_rotor
) == NULL
) {
720 mgnext
= mgprev
->mg_next
;
721 mg
->mg_prev
= mgprev
;
722 mg
->mg_next
= mgnext
;
723 mgprev
->mg_next
= mg
;
724 mgnext
->mg_prev
= mg
;
730 * Passivate a metaslab group and remove it from the allocation rotor.
731 * Callers must hold both the SCL_ALLOC and SCL_ZIO lock prior to passivating
732 * a metaslab group. This function will momentarily drop spa_config_locks
733 * that are lower than the SCL_ALLOC lock (see comment below).
736 metaslab_group_passivate(metaslab_group_t
*mg
)
738 metaslab_class_t
*mc
= mg
->mg_class
;
739 spa_t
*spa
= mc
->mc_spa
;
740 metaslab_group_t
*mgprev
, *mgnext
;
741 int locks
= spa_config_held(spa
, SCL_ALL
, RW_WRITER
);
743 ASSERT3U(spa_config_held(spa
, SCL_ALLOC
| SCL_ZIO
, RW_WRITER
), ==,
744 (SCL_ALLOC
| SCL_ZIO
));
746 if (--mg
->mg_activation_count
!= 0) {
747 ASSERT(mc
->mc_rotor
!= mg
);
748 ASSERT(mg
->mg_prev
== NULL
);
749 ASSERT(mg
->mg_next
== NULL
);
750 ASSERT(mg
->mg_activation_count
< 0);
755 * The spa_config_lock is an array of rwlocks, ordered as
756 * follows (from highest to lowest):
757 * SCL_CONFIG > SCL_STATE > SCL_L2ARC > SCL_ALLOC >
758 * SCL_ZIO > SCL_FREE > SCL_VDEV
759 * (For more information about the spa_config_lock see spa_misc.c)
760 * The higher the lock, the broader its coverage. When we passivate
761 * a metaslab group, we must hold both the SCL_ALLOC and the SCL_ZIO
762 * config locks. However, the metaslab group's taskq might be trying
763 * to preload metaslabs so we must drop the SCL_ZIO lock and any
764 * lower locks to allow the I/O to complete. At a minimum,
765 * we continue to hold the SCL_ALLOC lock, which prevents any future
766 * allocations from taking place and any changes to the vdev tree.
768 spa_config_exit(spa
, locks
& ~(SCL_ZIO
- 1), spa
);
769 taskq_wait(mg
->mg_taskq
);
770 spa_config_enter(spa
, locks
& ~(SCL_ZIO
- 1), spa
, RW_WRITER
);
771 metaslab_group_alloc_update(mg
);
772 for (int i
= 0; i
< mg
->mg_allocators
; i
++) {
773 metaslab_t
*msp
= mg
->mg_primaries
[i
];
775 mutex_enter(&msp
->ms_lock
);
776 metaslab_passivate(msp
,
777 metaslab_weight_from_range_tree(msp
));
778 mutex_exit(&msp
->ms_lock
);
780 msp
= mg
->mg_secondaries
[i
];
782 mutex_enter(&msp
->ms_lock
);
783 metaslab_passivate(msp
,
784 metaslab_weight_from_range_tree(msp
));
785 mutex_exit(&msp
->ms_lock
);
789 mgprev
= mg
->mg_prev
;
790 mgnext
= mg
->mg_next
;
795 mc
->mc_rotor
= mgnext
;
796 mgprev
->mg_next
= mgnext
;
797 mgnext
->mg_prev
= mgprev
;
805 metaslab_group_initialized(metaslab_group_t
*mg
)
807 vdev_t
*vd
= mg
->mg_vd
;
808 vdev_stat_t
*vs
= &vd
->vdev_stat
;
810 return (vs
->vs_space
!= 0 && mg
->mg_activation_count
> 0);
814 metaslab_group_get_space(metaslab_group_t
*mg
)
816 return ((1ULL << mg
->mg_vd
->vdev_ms_shift
) * mg
->mg_vd
->vdev_ms_count
);
820 metaslab_group_histogram_verify(metaslab_group_t
*mg
)
823 vdev_t
*vd
= mg
->mg_vd
;
824 uint64_t ashift
= vd
->vdev_ashift
;
827 if ((zfs_flags
& ZFS_DEBUG_HISTOGRAM_VERIFY
) == 0)
830 mg_hist
= kmem_zalloc(sizeof (uint64_t) * RANGE_TREE_HISTOGRAM_SIZE
,
833 ASSERT3U(RANGE_TREE_HISTOGRAM_SIZE
, >=,
834 SPACE_MAP_HISTOGRAM_SIZE
+ ashift
);
836 for (int m
= 0; m
< vd
->vdev_ms_count
; m
++) {
837 metaslab_t
*msp
= vd
->vdev_ms
[m
];
839 if (msp
->ms_sm
== NULL
)
842 for (i
= 0; i
< SPACE_MAP_HISTOGRAM_SIZE
; i
++)
843 mg_hist
[i
+ ashift
] +=
844 msp
->ms_sm
->sm_phys
->smp_histogram
[i
];
847 for (i
= 0; i
< RANGE_TREE_HISTOGRAM_SIZE
; i
++)
848 VERIFY3U(mg_hist
[i
], ==, mg
->mg_histogram
[i
]);
850 kmem_free(mg_hist
, sizeof (uint64_t) * RANGE_TREE_HISTOGRAM_SIZE
);
854 metaslab_group_histogram_add(metaslab_group_t
*mg
, metaslab_t
*msp
)
856 metaslab_class_t
*mc
= mg
->mg_class
;
857 uint64_t ashift
= mg
->mg_vd
->vdev_ashift
;
859 ASSERT(MUTEX_HELD(&msp
->ms_lock
));
860 if (msp
->ms_sm
== NULL
)
863 mutex_enter(&mg
->mg_lock
);
864 for (int i
= 0; i
< SPACE_MAP_HISTOGRAM_SIZE
; i
++) {
865 mg
->mg_histogram
[i
+ ashift
] +=
866 msp
->ms_sm
->sm_phys
->smp_histogram
[i
];
867 mc
->mc_histogram
[i
+ ashift
] +=
868 msp
->ms_sm
->sm_phys
->smp_histogram
[i
];
870 mutex_exit(&mg
->mg_lock
);
874 metaslab_group_histogram_remove(metaslab_group_t
*mg
, metaslab_t
*msp
)
876 metaslab_class_t
*mc
= mg
->mg_class
;
877 uint64_t ashift
= mg
->mg_vd
->vdev_ashift
;
879 ASSERT(MUTEX_HELD(&msp
->ms_lock
));
880 if (msp
->ms_sm
== NULL
)
883 mutex_enter(&mg
->mg_lock
);
884 for (int i
= 0; i
< SPACE_MAP_HISTOGRAM_SIZE
; i
++) {
885 ASSERT3U(mg
->mg_histogram
[i
+ ashift
], >=,
886 msp
->ms_sm
->sm_phys
->smp_histogram
[i
]);
887 ASSERT3U(mc
->mc_histogram
[i
+ ashift
], >=,
888 msp
->ms_sm
->sm_phys
->smp_histogram
[i
]);
890 mg
->mg_histogram
[i
+ ashift
] -=
891 msp
->ms_sm
->sm_phys
->smp_histogram
[i
];
892 mc
->mc_histogram
[i
+ ashift
] -=
893 msp
->ms_sm
->sm_phys
->smp_histogram
[i
];
895 mutex_exit(&mg
->mg_lock
);
899 metaslab_group_add(metaslab_group_t
*mg
, metaslab_t
*msp
)
901 ASSERT(msp
->ms_group
== NULL
);
902 mutex_enter(&mg
->mg_lock
);
905 avl_add(&mg
->mg_metaslab_tree
, msp
);
906 mutex_exit(&mg
->mg_lock
);
908 mutex_enter(&msp
->ms_lock
);
909 metaslab_group_histogram_add(mg
, msp
);
910 mutex_exit(&msp
->ms_lock
);
914 metaslab_group_remove(metaslab_group_t
*mg
, metaslab_t
*msp
)
916 mutex_enter(&msp
->ms_lock
);
917 metaslab_group_histogram_remove(mg
, msp
);
918 mutex_exit(&msp
->ms_lock
);
920 mutex_enter(&mg
->mg_lock
);
921 ASSERT(msp
->ms_group
== mg
);
922 avl_remove(&mg
->mg_metaslab_tree
, msp
);
923 msp
->ms_group
= NULL
;
924 mutex_exit(&mg
->mg_lock
);
928 metaslab_group_sort_impl(metaslab_group_t
*mg
, metaslab_t
*msp
, uint64_t weight
)
930 ASSERT(MUTEX_HELD(&mg
->mg_lock
));
931 ASSERT(msp
->ms_group
== mg
);
932 avl_remove(&mg
->mg_metaslab_tree
, msp
);
933 msp
->ms_weight
= weight
;
934 avl_add(&mg
->mg_metaslab_tree
, msp
);
939 metaslab_group_sort(metaslab_group_t
*mg
, metaslab_t
*msp
, uint64_t weight
)
942 * Although in principle the weight can be any value, in
943 * practice we do not use values in the range [1, 511].
945 ASSERT(weight
>= SPA_MINBLOCKSIZE
|| weight
== 0);
946 ASSERT(MUTEX_HELD(&msp
->ms_lock
));
948 mutex_enter(&mg
->mg_lock
);
949 metaslab_group_sort_impl(mg
, msp
, weight
);
950 mutex_exit(&mg
->mg_lock
);
954 * Calculate the fragmentation for a given metaslab group. We can use
955 * a simple average here since all metaslabs within the group must have
956 * the same size. The return value will be a value between 0 and 100
957 * (inclusive), or ZFS_FRAG_INVALID if less than half of the metaslab in this
958 * group have a fragmentation metric.
961 metaslab_group_fragmentation(metaslab_group_t
*mg
)
963 vdev_t
*vd
= mg
->mg_vd
;
964 uint64_t fragmentation
= 0;
965 uint64_t valid_ms
= 0;
967 for (int m
= 0; m
< vd
->vdev_ms_count
; m
++) {
968 metaslab_t
*msp
= vd
->vdev_ms
[m
];
970 if (msp
->ms_fragmentation
== ZFS_FRAG_INVALID
)
974 fragmentation
+= msp
->ms_fragmentation
;
977 if (valid_ms
<= vd
->vdev_ms_count
/ 2)
978 return (ZFS_FRAG_INVALID
);
980 fragmentation
/= valid_ms
;
981 ASSERT3U(fragmentation
, <=, 100);
982 return (fragmentation
);
986 * Determine if a given metaslab group should skip allocations. A metaslab
987 * group should avoid allocations if its free capacity is less than the
988 * zfs_mg_noalloc_threshold or its fragmentation metric is greater than
989 * zfs_mg_fragmentation_threshold and there is at least one metaslab group
990 * that can still handle allocations. If the allocation throttle is enabled
991 * then we skip allocations to devices that have reached their maximum
992 * allocation queue depth unless the selected metaslab group is the only
993 * eligible group remaining.
996 metaslab_group_allocatable(metaslab_group_t
*mg
, metaslab_group_t
*rotor
,
997 uint64_t psize
, int allocator
)
999 spa_t
*spa
= mg
->mg_vd
->vdev_spa
;
1000 metaslab_class_t
*mc
= mg
->mg_class
;
1003 * We can only consider skipping this metaslab group if it's
1004 * in the normal metaslab class and there are other metaslab
1005 * groups to select from. Otherwise, we always consider it eligible
1008 if (mc
!= spa_normal_class(spa
) || mc
->mc_groups
<= 1)
1012 * If the metaslab group's mg_allocatable flag is set (see comments
1013 * in metaslab_group_alloc_update() for more information) and
1014 * the allocation throttle is disabled then allow allocations to this
1015 * device. However, if the allocation throttle is enabled then
1016 * check if we have reached our allocation limit (mg_alloc_queue_depth)
1017 * to determine if we should allow allocations to this metaslab group.
1018 * If all metaslab groups are no longer considered allocatable
1019 * (mc_alloc_groups == 0) or we're trying to allocate the smallest
1020 * gang block size then we allow allocations on this metaslab group
1021 * regardless of the mg_allocatable or throttle settings.
1023 if (mg
->mg_allocatable
) {
1024 metaslab_group_t
*mgp
;
1026 uint64_t qmax
= mg
->mg_cur_max_alloc_queue_depth
[allocator
];
1028 if (!mc
->mc_alloc_throttle_enabled
)
1032 * If this metaslab group does not have any free space, then
1033 * there is no point in looking further.
1035 if (mg
->mg_no_free_space
)
1038 qdepth
= refcount_count(&mg
->mg_alloc_queue_depth
[allocator
]);
1041 * If this metaslab group is below its qmax or it's
1042 * the only allocatable metasable group, then attempt
1043 * to allocate from it.
1045 if (qdepth
< qmax
|| mc
->mc_alloc_groups
== 1)
1047 ASSERT3U(mc
->mc_alloc_groups
, >, 1);
1050 * Since this metaslab group is at or over its qmax, we
1051 * need to determine if there are metaslab groups after this
1052 * one that might be able to handle this allocation. This is
1053 * racy since we can't hold the locks for all metaslab
1054 * groups at the same time when we make this check.
1056 for (mgp
= mg
->mg_next
; mgp
!= rotor
; mgp
= mgp
->mg_next
) {
1057 qmax
= mgp
->mg_cur_max_alloc_queue_depth
[allocator
];
1059 qdepth
= refcount_count(
1060 &mgp
->mg_alloc_queue_depth
[allocator
]);
1063 * If there is another metaslab group that
1064 * might be able to handle the allocation, then
1065 * we return false so that we skip this group.
1067 if (qdepth
< qmax
&& !mgp
->mg_no_free_space
)
1072 * We didn't find another group to handle the allocation
1073 * so we can't skip this metaslab group even though
1074 * we are at or over our qmax.
1078 } else if (mc
->mc_alloc_groups
== 0 || psize
== SPA_MINBLOCKSIZE
) {
1085 * ==========================================================================
1086 * Range tree callbacks
1087 * ==========================================================================
1091 * Comparison function for the private size-ordered tree. Tree is sorted
1092 * by size, larger sizes at the end of the tree.
1095 metaslab_rangesize_compare(const void *x1
, const void *x2
)
1097 const range_seg_t
*r1
= x1
;
1098 const range_seg_t
*r2
= x2
;
1099 uint64_t rs_size1
= r1
->rs_end
- r1
->rs_start
;
1100 uint64_t rs_size2
= r2
->rs_end
- r2
->rs_start
;
1102 if (rs_size1
< rs_size2
)
1104 if (rs_size1
> rs_size2
)
1107 if (r1
->rs_start
< r2
->rs_start
)
1110 if (r1
->rs_start
> r2
->rs_start
)
1117 * Create any block allocator specific components. The current allocators
1118 * rely on using both a size-ordered range_tree_t and an array of uint64_t's.
1121 metaslab_rt_create(range_tree_t
*rt
, void *arg
)
1123 metaslab_t
*msp
= arg
;
1125 ASSERT3P(rt
->rt_arg
, ==, msp
);
1126 ASSERT(msp
->ms_allocatable
== NULL
);
1128 avl_create(&msp
->ms_allocatable_by_size
, metaslab_rangesize_compare
,
1129 sizeof (range_seg_t
), offsetof(range_seg_t
, rs_pp_node
));
1133 * Destroy the block allocator specific components.
1136 metaslab_rt_destroy(range_tree_t
*rt
, void *arg
)
1138 metaslab_t
*msp
= arg
;
1140 ASSERT3P(rt
->rt_arg
, ==, msp
);
1141 ASSERT3P(msp
->ms_allocatable
, ==, rt
);
1142 ASSERT0(avl_numnodes(&msp
->ms_allocatable_by_size
));
1144 avl_destroy(&msp
->ms_allocatable_by_size
);
1148 metaslab_rt_add(range_tree_t
*rt
, range_seg_t
*rs
, void *arg
)
1150 metaslab_t
*msp
= arg
;
1152 ASSERT3P(rt
->rt_arg
, ==, msp
);
1153 ASSERT3P(msp
->ms_allocatable
, ==, rt
);
1154 VERIFY(!msp
->ms_condensing
);
1155 avl_add(&msp
->ms_allocatable_by_size
, rs
);
1159 metaslab_rt_remove(range_tree_t
*rt
, range_seg_t
*rs
, void *arg
)
1161 metaslab_t
*msp
= arg
;
1163 ASSERT3P(rt
->rt_arg
, ==, msp
);
1164 ASSERT3P(msp
->ms_allocatable
, ==, rt
);
1165 VERIFY(!msp
->ms_condensing
);
1166 avl_remove(&msp
->ms_allocatable_by_size
, rs
);
1170 metaslab_rt_vacate(range_tree_t
*rt
, void *arg
)
1172 metaslab_t
*msp
= arg
;
1174 ASSERT3P(rt
->rt_arg
, ==, msp
);
1175 ASSERT3P(msp
->ms_allocatable
, ==, rt
);
1178 * Normally one would walk the tree freeing nodes along the way.
1179 * Since the nodes are shared with the range trees we can avoid
1180 * walking all nodes and just reinitialize the avl tree. The nodes
1181 * will be freed by the range tree, so we don't want to free them here.
1183 avl_create(&msp
->ms_allocatable_by_size
, metaslab_rangesize_compare
,
1184 sizeof (range_seg_t
), offsetof(range_seg_t
, rs_pp_node
));
1187 static range_tree_ops_t metaslab_rt_ops
= {
1189 metaslab_rt_destroy
,
1196 * ==========================================================================
1197 * Common allocator routines
1198 * ==========================================================================
1202 * Return the maximum contiguous segment within the metaslab.
1205 metaslab_block_maxsize(metaslab_t
*msp
)
1207 avl_tree_t
*t
= &msp
->ms_allocatable_by_size
;
1210 if (t
== NULL
|| (rs
= avl_last(t
)) == NULL
)
1213 return (rs
->rs_end
- rs
->rs_start
);
1216 static range_seg_t
*
1217 metaslab_block_find(avl_tree_t
*t
, uint64_t start
, uint64_t size
)
1219 range_seg_t
*rs
, rsearch
;
1222 rsearch
.rs_start
= start
;
1223 rsearch
.rs_end
= start
+ size
;
1225 rs
= avl_find(t
, &rsearch
, &where
);
1227 rs
= avl_nearest(t
, where
, AVL_AFTER
);
1234 * This is a helper function that can be used by the allocator to find
1235 * a suitable block to allocate. This will search the specified AVL
1236 * tree looking for a block that matches the specified criteria.
1239 metaslab_block_picker(avl_tree_t
*t
, uint64_t *cursor
, uint64_t size
,
1242 range_seg_t
*rs
= metaslab_block_find(t
, *cursor
, size
);
1244 while (rs
!= NULL
) {
1245 uint64_t offset
= P2ROUNDUP(rs
->rs_start
, align
);
1247 if (offset
+ size
<= rs
->rs_end
) {
1248 *cursor
= offset
+ size
;
1251 rs
= AVL_NEXT(t
, rs
);
1255 * If we know we've searched the whole map (*cursor == 0), give up.
1256 * Otherwise, reset the cursor to the beginning and try again.
1262 return (metaslab_block_picker(t
, cursor
, size
, align
));
1266 * ==========================================================================
1267 * The first-fit block allocator
1268 * ==========================================================================
1271 metaslab_ff_alloc(metaslab_t
*msp
, uint64_t size
)
1274 * Find the largest power of 2 block size that evenly divides the
1275 * requested size. This is used to try to allocate blocks with similar
1276 * alignment from the same area of the metaslab (i.e. same cursor
1277 * bucket) but it does not guarantee that other allocations sizes
1278 * may exist in the same region.
1280 uint64_t align
= size
& -size
;
1281 uint64_t *cursor
= &msp
->ms_lbas
[highbit64(align
) - 1];
1282 avl_tree_t
*t
= &msp
->ms_allocatable
->rt_root
;
1284 return (metaslab_block_picker(t
, cursor
, size
, align
));
1287 static metaslab_ops_t metaslab_ff_ops
= {
1292 * ==========================================================================
1293 * Dynamic block allocator -
1294 * Uses the first fit allocation scheme until space get low and then
1295 * adjusts to a best fit allocation method. Uses metaslab_df_alloc_threshold
1296 * and metaslab_df_free_pct to determine when to switch the allocation scheme.
1297 * ==========================================================================
1300 metaslab_df_alloc(metaslab_t
*msp
, uint64_t size
)
1303 * Find the largest power of 2 block size that evenly divides the
1304 * requested size. This is used to try to allocate blocks with similar
1305 * alignment from the same area of the metaslab (i.e. same cursor
1306 * bucket) but it does not guarantee that other allocations sizes
1307 * may exist in the same region.
1309 uint64_t align
= size
& -size
;
1310 uint64_t *cursor
= &msp
->ms_lbas
[highbit64(align
) - 1];
1311 range_tree_t
*rt
= msp
->ms_allocatable
;
1312 avl_tree_t
*t
= &rt
->rt_root
;
1313 uint64_t max_size
= metaslab_block_maxsize(msp
);
1314 int free_pct
= range_tree_space(rt
) * 100 / msp
->ms_size
;
1316 ASSERT(MUTEX_HELD(&msp
->ms_lock
));
1317 ASSERT3U(avl_numnodes(t
), ==,
1318 avl_numnodes(&msp
->ms_allocatable_by_size
));
1320 if (max_size
< size
)
1324 * If we're running low on space switch to using the size
1325 * sorted AVL tree (best-fit).
1327 if (max_size
< metaslab_df_alloc_threshold
||
1328 free_pct
< metaslab_df_free_pct
) {
1329 t
= &msp
->ms_allocatable_by_size
;
1333 return (metaslab_block_picker(t
, cursor
, size
, 1ULL));
1336 static metaslab_ops_t metaslab_df_ops
= {
1341 * ==========================================================================
1342 * Cursor fit block allocator -
1343 * Select the largest region in the metaslab, set the cursor to the beginning
1344 * of the range and the cursor_end to the end of the range. As allocations
1345 * are made advance the cursor. Continue allocating from the cursor until
1346 * the range is exhausted and then find a new range.
1347 * ==========================================================================
1350 metaslab_cf_alloc(metaslab_t
*msp
, uint64_t size
)
1352 range_tree_t
*rt
= msp
->ms_allocatable
;
1353 avl_tree_t
*t
= &msp
->ms_allocatable_by_size
;
1354 uint64_t *cursor
= &msp
->ms_lbas
[0];
1355 uint64_t *cursor_end
= &msp
->ms_lbas
[1];
1356 uint64_t offset
= 0;
1358 ASSERT(MUTEX_HELD(&msp
->ms_lock
));
1359 ASSERT3U(avl_numnodes(t
), ==, avl_numnodes(&rt
->rt_root
));
1361 ASSERT3U(*cursor_end
, >=, *cursor
);
1363 if ((*cursor
+ size
) > *cursor_end
) {
1366 rs
= avl_last(&msp
->ms_allocatable_by_size
);
1367 if (rs
== NULL
|| (rs
->rs_end
- rs
->rs_start
) < size
)
1370 *cursor
= rs
->rs_start
;
1371 *cursor_end
= rs
->rs_end
;
1380 static metaslab_ops_t metaslab_cf_ops
= {
1385 * ==========================================================================
1386 * New dynamic fit allocator -
1387 * Select a region that is large enough to allocate 2^metaslab_ndf_clump_shift
1388 * contiguous blocks. If no region is found then just use the largest segment
1390 * ==========================================================================
1394 * Determines desired number of contiguous blocks (2^metaslab_ndf_clump_shift)
1395 * to request from the allocator.
1397 uint64_t metaslab_ndf_clump_shift
= 4;
1400 metaslab_ndf_alloc(metaslab_t
*msp
, uint64_t size
)
1402 avl_tree_t
*t
= &msp
->ms_allocatable
->rt_root
;
1404 range_seg_t
*rs
, rsearch
;
1405 uint64_t hbit
= highbit64(size
);
1406 uint64_t *cursor
= &msp
->ms_lbas
[hbit
- 1];
1407 uint64_t max_size
= metaslab_block_maxsize(msp
);
1409 ASSERT(MUTEX_HELD(&msp
->ms_lock
));
1410 ASSERT3U(avl_numnodes(t
), ==,
1411 avl_numnodes(&msp
->ms_allocatable_by_size
));
1413 if (max_size
< size
)
1416 rsearch
.rs_start
= *cursor
;
1417 rsearch
.rs_end
= *cursor
+ size
;
1419 rs
= avl_find(t
, &rsearch
, &where
);
1420 if (rs
== NULL
|| (rs
->rs_end
- rs
->rs_start
) < size
) {
1421 t
= &msp
->ms_allocatable_by_size
;
1423 rsearch
.rs_start
= 0;
1424 rsearch
.rs_end
= MIN(max_size
,
1425 1ULL << (hbit
+ metaslab_ndf_clump_shift
));
1426 rs
= avl_find(t
, &rsearch
, &where
);
1428 rs
= avl_nearest(t
, where
, AVL_AFTER
);
1432 if ((rs
->rs_end
- rs
->rs_start
) >= size
) {
1433 *cursor
= rs
->rs_start
+ size
;
1434 return (rs
->rs_start
);
1439 static metaslab_ops_t metaslab_ndf_ops
= {
1443 metaslab_ops_t
*zfs_metaslab_ops
= &metaslab_df_ops
;
1446 * ==========================================================================
1448 * ==========================================================================
1452 * Wait for any in-progress metaslab loads to complete.
1455 metaslab_load_wait(metaslab_t
*msp
)
1457 ASSERT(MUTEX_HELD(&msp
->ms_lock
));
1459 while (msp
->ms_loading
) {
1460 ASSERT(!msp
->ms_loaded
);
1461 cv_wait(&msp
->ms_load_cv
, &msp
->ms_lock
);
1466 metaslab_load(metaslab_t
*msp
)
1469 boolean_t success
= B_FALSE
;
1471 ASSERT(MUTEX_HELD(&msp
->ms_lock
));
1472 ASSERT(!msp
->ms_loaded
);
1473 ASSERT(!msp
->ms_loading
);
1475 msp
->ms_loading
= B_TRUE
;
1477 * Nobody else can manipulate a loading metaslab, so it's now safe
1478 * to drop the lock. This way we don't have to hold the lock while
1479 * reading the spacemap from disk.
1481 mutex_exit(&msp
->ms_lock
);
1484 * If the space map has not been allocated yet, then treat
1485 * all the space in the metaslab as free and add it to ms_allocatable.
1487 if (msp
->ms_sm
!= NULL
) {
1488 error
= space_map_load(msp
->ms_sm
, msp
->ms_allocatable
,
1491 range_tree_add(msp
->ms_allocatable
,
1492 msp
->ms_start
, msp
->ms_size
);
1495 success
= (error
== 0);
1497 mutex_enter(&msp
->ms_lock
);
1498 msp
->ms_loading
= B_FALSE
;
1501 ASSERT3P(msp
->ms_group
, !=, NULL
);
1502 msp
->ms_loaded
= B_TRUE
;
1505 * If the metaslab already has a spacemap, then we need to
1506 * remove all segments from the defer tree; otherwise, the
1507 * metaslab is completely empty and we can skip this.
1509 if (msp
->ms_sm
!= NULL
) {
1510 for (int t
= 0; t
< TXG_DEFER_SIZE
; t
++) {
1511 range_tree_walk(msp
->ms_defer
[t
],
1512 range_tree_remove
, msp
->ms_allocatable
);
1515 msp
->ms_max_size
= metaslab_block_maxsize(msp
);
1517 cv_broadcast(&msp
->ms_load_cv
);
1522 metaslab_unload(metaslab_t
*msp
)
1524 ASSERT(MUTEX_HELD(&msp
->ms_lock
));
1525 range_tree_vacate(msp
->ms_allocatable
, NULL
, NULL
);
1526 msp
->ms_loaded
= B_FALSE
;
1527 msp
->ms_weight
&= ~METASLAB_ACTIVE_MASK
;
1528 msp
->ms_max_size
= 0;
1532 metaslab_init(metaslab_group_t
*mg
, uint64_t id
, uint64_t object
, uint64_t txg
,
1535 vdev_t
*vd
= mg
->mg_vd
;
1536 objset_t
*mos
= vd
->vdev_spa
->spa_meta_objset
;
1540 ms
= kmem_zalloc(sizeof (metaslab_t
), KM_SLEEP
);
1541 mutex_init(&ms
->ms_lock
, NULL
, MUTEX_DEFAULT
, NULL
);
1542 mutex_init(&ms
->ms_sync_lock
, NULL
, MUTEX_DEFAULT
, NULL
);
1543 cv_init(&ms
->ms_load_cv
, NULL
, CV_DEFAULT
, NULL
);
1545 ms
->ms_start
= id
<< vd
->vdev_ms_shift
;
1546 ms
->ms_size
= 1ULL << vd
->vdev_ms_shift
;
1547 ms
->ms_allocator
= -1;
1548 ms
->ms_new
= B_TRUE
;
1551 * We only open space map objects that already exist. All others
1552 * will be opened when we finally allocate an object for it.
1555 error
= space_map_open(&ms
->ms_sm
, mos
, object
, ms
->ms_start
,
1556 ms
->ms_size
, vd
->vdev_ashift
);
1559 kmem_free(ms
, sizeof (metaslab_t
));
1563 ASSERT(ms
->ms_sm
!= NULL
);
1567 * We create the main range tree here, but we don't create the
1568 * other range trees until metaslab_sync_done(). This serves
1569 * two purposes: it allows metaslab_sync_done() to detect the
1570 * addition of new space; and for debugging, it ensures that we'd
1571 * data fault on any attempt to use this metaslab before it's ready.
1573 ms
->ms_allocatable
= range_tree_create(&metaslab_rt_ops
, ms
);
1574 metaslab_group_add(mg
, ms
);
1576 metaslab_set_fragmentation(ms
);
1579 * If we're opening an existing pool (txg == 0) or creating
1580 * a new one (txg == TXG_INITIAL), all space is available now.
1581 * If we're adding space to an existing pool, the new space
1582 * does not become available until after this txg has synced.
1583 * The metaslab's weight will also be initialized when we sync
1584 * out this txg. This ensures that we don't attempt to allocate
1585 * from it before we have initialized it completely.
1587 if (txg
<= TXG_INITIAL
)
1588 metaslab_sync_done(ms
, 0);
1591 * If metaslab_debug_load is set and we're initializing a metaslab
1592 * that has an allocated space map object then load the its space
1593 * map so that can verify frees.
1595 if (metaslab_debug_load
&& ms
->ms_sm
!= NULL
) {
1596 mutex_enter(&ms
->ms_lock
);
1597 VERIFY0(metaslab_load(ms
));
1598 mutex_exit(&ms
->ms_lock
);
1602 vdev_dirty(vd
, 0, NULL
, txg
);
1603 vdev_dirty(vd
, VDD_METASLAB
, ms
, txg
);
1612 metaslab_fini(metaslab_t
*msp
)
1614 metaslab_group_t
*mg
= msp
->ms_group
;
1616 metaslab_group_remove(mg
, msp
);
1618 mutex_enter(&msp
->ms_lock
);
1619 VERIFY(msp
->ms_group
== NULL
);
1620 vdev_space_update(mg
->mg_vd
, -space_map_allocated(msp
->ms_sm
),
1622 space_map_close(msp
->ms_sm
);
1624 metaslab_unload(msp
);
1625 range_tree_destroy(msp
->ms_allocatable
);
1626 range_tree_destroy(msp
->ms_freeing
);
1627 range_tree_destroy(msp
->ms_freed
);
1629 for (int t
= 0; t
< TXG_SIZE
; t
++) {
1630 range_tree_destroy(msp
->ms_allocating
[t
]);
1633 for (int t
= 0; t
< TXG_DEFER_SIZE
; t
++) {
1634 range_tree_destroy(msp
->ms_defer
[t
]);
1636 ASSERT0(msp
->ms_deferspace
);
1638 range_tree_destroy(msp
->ms_checkpointing
);
1640 mutex_exit(&msp
->ms_lock
);
1641 cv_destroy(&msp
->ms_load_cv
);
1642 mutex_destroy(&msp
->ms_lock
);
1643 mutex_destroy(&msp
->ms_sync_lock
);
1644 ASSERT3U(msp
->ms_allocator
, ==, -1);
1646 kmem_free(msp
, sizeof (metaslab_t
));
1649 #define FRAGMENTATION_TABLE_SIZE 17
1652 * This table defines a segment size based fragmentation metric that will
1653 * allow each metaslab to derive its own fragmentation value. This is done
1654 * by calculating the space in each bucket of the spacemap histogram and
1655 * multiplying that by the fragmetation metric in this table. Doing
1656 * this for all buckets and dividing it by the total amount of free
1657 * space in this metaslab (i.e. the total free space in all buckets) gives
1658 * us the fragmentation metric. This means that a high fragmentation metric
1659 * equates to most of the free space being comprised of small segments.
1660 * Conversely, if the metric is low, then most of the free space is in
1661 * large segments. A 10% change in fragmentation equates to approximately
1662 * double the number of segments.
1664 * This table defines 0% fragmented space using 16MB segments. Testing has
1665 * shown that segments that are greater than or equal to 16MB do not suffer
1666 * from drastic performance problems. Using this value, we derive the rest
1667 * of the table. Since the fragmentation value is never stored on disk, it
1668 * is possible to change these calculations in the future.
1670 int zfs_frag_table
[FRAGMENTATION_TABLE_SIZE
] = {
1690 * Calclate the metaslab's fragmentation metric. A return value
1691 * of ZFS_FRAG_INVALID means that the metaslab has not been upgraded and does
1692 * not support this metric. Otherwise, the return value should be in the
1696 metaslab_set_fragmentation(metaslab_t
*msp
)
1698 spa_t
*spa
= msp
->ms_group
->mg_vd
->vdev_spa
;
1699 uint64_t fragmentation
= 0;
1701 boolean_t feature_enabled
= spa_feature_is_enabled(spa
,
1702 SPA_FEATURE_SPACEMAP_HISTOGRAM
);
1704 if (!feature_enabled
) {
1705 msp
->ms_fragmentation
= ZFS_FRAG_INVALID
;
1710 * A null space map means that the entire metaslab is free
1711 * and thus is not fragmented.
1713 if (msp
->ms_sm
== NULL
) {
1714 msp
->ms_fragmentation
= 0;
1719 * If this metaslab's space map has not been upgraded, flag it
1720 * so that we upgrade next time we encounter it.
1722 if (msp
->ms_sm
->sm_dbuf
->db_size
!= sizeof (space_map_phys_t
)) {
1723 uint64_t txg
= spa_syncing_txg(spa
);
1724 vdev_t
*vd
= msp
->ms_group
->mg_vd
;
1727 * If we've reached the final dirty txg, then we must
1728 * be shutting down the pool. We don't want to dirty
1729 * any data past this point so skip setting the condense
1730 * flag. We can retry this action the next time the pool
1733 if (spa_writeable(spa
) && txg
< spa_final_dirty_txg(spa
)) {
1734 msp
->ms_condense_wanted
= B_TRUE
;
1735 vdev_dirty(vd
, VDD_METASLAB
, msp
, txg
+ 1);
1736 spa_dbgmsg(spa
, "txg %llu, requesting force condense: "
1737 "ms_id %llu, vdev_id %llu", txg
, msp
->ms_id
,
1740 msp
->ms_fragmentation
= ZFS_FRAG_INVALID
;
1744 for (int i
= 0; i
< SPACE_MAP_HISTOGRAM_SIZE
; i
++) {
1746 uint8_t shift
= msp
->ms_sm
->sm_shift
;
1748 int idx
= MIN(shift
- SPA_MINBLOCKSHIFT
+ i
,
1749 FRAGMENTATION_TABLE_SIZE
- 1);
1751 if (msp
->ms_sm
->sm_phys
->smp_histogram
[i
] == 0)
1754 space
= msp
->ms_sm
->sm_phys
->smp_histogram
[i
] << (i
+ shift
);
1757 ASSERT3U(idx
, <, FRAGMENTATION_TABLE_SIZE
);
1758 fragmentation
+= space
* zfs_frag_table
[idx
];
1762 fragmentation
/= total
;
1763 ASSERT3U(fragmentation
, <=, 100);
1765 msp
->ms_fragmentation
= fragmentation
;
1769 * Compute a weight -- a selection preference value -- for the given metaslab.
1770 * This is based on the amount of free space, the level of fragmentation,
1771 * the LBA range, and whether the metaslab is loaded.
1774 metaslab_space_weight(metaslab_t
*msp
)
1776 metaslab_group_t
*mg
= msp
->ms_group
;
1777 vdev_t
*vd
= mg
->mg_vd
;
1778 uint64_t weight
, space
;
1780 ASSERT(MUTEX_HELD(&msp
->ms_lock
));
1781 ASSERT(!vd
->vdev_removing
);
1784 * The baseline weight is the metaslab's free space.
1786 space
= msp
->ms_size
- space_map_allocated(msp
->ms_sm
);
1788 if (metaslab_fragmentation_factor_enabled
&&
1789 msp
->ms_fragmentation
!= ZFS_FRAG_INVALID
) {
1791 * Use the fragmentation information to inversely scale
1792 * down the baseline weight. We need to ensure that we
1793 * don't exclude this metaslab completely when it's 100%
1794 * fragmented. To avoid this we reduce the fragmented value
1797 space
= (space
* (100 - (msp
->ms_fragmentation
- 1))) / 100;
1800 * If space < SPA_MINBLOCKSIZE, then we will not allocate from
1801 * this metaslab again. The fragmentation metric may have
1802 * decreased the space to something smaller than
1803 * SPA_MINBLOCKSIZE, so reset the space to SPA_MINBLOCKSIZE
1804 * so that we can consume any remaining space.
1806 if (space
> 0 && space
< SPA_MINBLOCKSIZE
)
1807 space
= SPA_MINBLOCKSIZE
;
1812 * Modern disks have uniform bit density and constant angular velocity.
1813 * Therefore, the outer recording zones are faster (higher bandwidth)
1814 * than the inner zones by the ratio of outer to inner track diameter,
1815 * which is typically around 2:1. We account for this by assigning
1816 * higher weight to lower metaslabs (multiplier ranging from 2x to 1x).
1817 * In effect, this means that we'll select the metaslab with the most
1818 * free bandwidth rather than simply the one with the most free space.
1820 if (metaslab_lba_weighting_enabled
) {
1821 weight
= 2 * weight
- (msp
->ms_id
* weight
) / vd
->vdev_ms_count
;
1822 ASSERT(weight
>= space
&& weight
<= 2 * space
);
1826 * If this metaslab is one we're actively using, adjust its
1827 * weight to make it preferable to any inactive metaslab so
1828 * we'll polish it off. If the fragmentation on this metaslab
1829 * has exceed our threshold, then don't mark it active.
1831 if (msp
->ms_loaded
&& msp
->ms_fragmentation
!= ZFS_FRAG_INVALID
&&
1832 msp
->ms_fragmentation
<= zfs_metaslab_fragmentation_threshold
) {
1833 weight
|= (msp
->ms_weight
& METASLAB_ACTIVE_MASK
);
1836 WEIGHT_SET_SPACEBASED(weight
);
1841 * Return the weight of the specified metaslab, according to the segment-based
1842 * weighting algorithm. The metaslab must be loaded. This function can
1843 * be called within a sync pass since it relies only on the metaslab's
1844 * range tree which is always accurate when the metaslab is loaded.
1847 metaslab_weight_from_range_tree(metaslab_t
*msp
)
1849 uint64_t weight
= 0;
1850 uint32_t segments
= 0;
1852 ASSERT(msp
->ms_loaded
);
1854 for (int i
= RANGE_TREE_HISTOGRAM_SIZE
- 1; i
>= SPA_MINBLOCKSHIFT
;
1856 uint8_t shift
= msp
->ms_group
->mg_vd
->vdev_ashift
;
1857 int max_idx
= SPACE_MAP_HISTOGRAM_SIZE
+ shift
- 1;
1860 segments
+= msp
->ms_allocatable
->rt_histogram
[i
];
1863 * The range tree provides more precision than the space map
1864 * and must be downgraded so that all values fit within the
1865 * space map's histogram. This allows us to compare loaded
1866 * vs. unloaded metaslabs to determine which metaslab is
1867 * considered "best".
1872 if (segments
!= 0) {
1873 WEIGHT_SET_COUNT(weight
, segments
);
1874 WEIGHT_SET_INDEX(weight
, i
);
1875 WEIGHT_SET_ACTIVE(weight
, 0);
1883 * Calculate the weight based on the on-disk histogram. This should only
1884 * be called after a sync pass has completely finished since the on-disk
1885 * information is updated in metaslab_sync().
1888 metaslab_weight_from_spacemap(metaslab_t
*msp
)
1890 uint64_t weight
= 0;
1892 for (int i
= SPACE_MAP_HISTOGRAM_SIZE
- 1; i
>= 0; i
--) {
1893 if (msp
->ms_sm
->sm_phys
->smp_histogram
[i
] != 0) {
1894 WEIGHT_SET_COUNT(weight
,
1895 msp
->ms_sm
->sm_phys
->smp_histogram
[i
]);
1896 WEIGHT_SET_INDEX(weight
, i
+
1897 msp
->ms_sm
->sm_shift
);
1898 WEIGHT_SET_ACTIVE(weight
, 0);
1906 * Compute a segment-based weight for the specified metaslab. The weight
1907 * is determined by highest bucket in the histogram. The information
1908 * for the highest bucket is encoded into the weight value.
1911 metaslab_segment_weight(metaslab_t
*msp
)
1913 metaslab_group_t
*mg
= msp
->ms_group
;
1914 uint64_t weight
= 0;
1915 uint8_t shift
= mg
->mg_vd
->vdev_ashift
;
1917 ASSERT(MUTEX_HELD(&msp
->ms_lock
));
1920 * The metaslab is completely free.
1922 if (space_map_allocated(msp
->ms_sm
) == 0) {
1923 int idx
= highbit64(msp
->ms_size
) - 1;
1924 int max_idx
= SPACE_MAP_HISTOGRAM_SIZE
+ shift
- 1;
1926 if (idx
< max_idx
) {
1927 WEIGHT_SET_COUNT(weight
, 1ULL);
1928 WEIGHT_SET_INDEX(weight
, idx
);
1930 WEIGHT_SET_COUNT(weight
, 1ULL << (idx
- max_idx
));
1931 WEIGHT_SET_INDEX(weight
, max_idx
);
1933 WEIGHT_SET_ACTIVE(weight
, 0);
1934 ASSERT(!WEIGHT_IS_SPACEBASED(weight
));
1939 ASSERT3U(msp
->ms_sm
->sm_dbuf
->db_size
, ==, sizeof (space_map_phys_t
));
1942 * If the metaslab is fully allocated then just make the weight 0.
1944 if (space_map_allocated(msp
->ms_sm
) == msp
->ms_size
)
1947 * If the metaslab is already loaded, then use the range tree to
1948 * determine the weight. Otherwise, we rely on the space map information
1949 * to generate the weight.
1951 if (msp
->ms_loaded
) {
1952 weight
= metaslab_weight_from_range_tree(msp
);
1954 weight
= metaslab_weight_from_spacemap(msp
);
1958 * If the metaslab was active the last time we calculated its weight
1959 * then keep it active. We want to consume the entire region that
1960 * is associated with this weight.
1962 if (msp
->ms_activation_weight
!= 0 && weight
!= 0)
1963 WEIGHT_SET_ACTIVE(weight
, WEIGHT_GET_ACTIVE(msp
->ms_weight
));
1968 * Determine if we should attempt to allocate from this metaslab. If the
1969 * metaslab has a maximum size then we can quickly determine if the desired
1970 * allocation size can be satisfied. Otherwise, if we're using segment-based
1971 * weighting then we can determine the maximum allocation that this metaslab
1972 * can accommodate based on the index encoded in the weight. If we're using
1973 * space-based weights then rely on the entire weight (excluding the weight
1977 metaslab_should_allocate(metaslab_t
*msp
, uint64_t asize
)
1979 boolean_t should_allocate
;
1981 if (msp
->ms_max_size
!= 0)
1982 return (msp
->ms_max_size
>= asize
);
1984 if (!WEIGHT_IS_SPACEBASED(msp
->ms_weight
)) {
1986 * The metaslab segment weight indicates segments in the
1987 * range [2^i, 2^(i+1)), where i is the index in the weight.
1988 * Since the asize might be in the middle of the range, we
1989 * should attempt the allocation if asize < 2^(i+1).
1991 should_allocate
= (asize
<
1992 1ULL << (WEIGHT_GET_INDEX(msp
->ms_weight
) + 1));
1994 should_allocate
= (asize
<=
1995 (msp
->ms_weight
& ~METASLAB_WEIGHT_TYPE
));
1997 return (should_allocate
);
2001 metaslab_weight(metaslab_t
*msp
)
2003 vdev_t
*vd
= msp
->ms_group
->mg_vd
;
2004 spa_t
*spa
= vd
->vdev_spa
;
2007 ASSERT(MUTEX_HELD(&msp
->ms_lock
));
2010 * If this vdev is in the process of being removed, there is nothing
2011 * for us to do here.
2013 if (vd
->vdev_removing
)
2016 metaslab_set_fragmentation(msp
);
2019 * Update the maximum size if the metaslab is loaded. This will
2020 * ensure that we get an accurate maximum size if newly freed space
2021 * has been added back into the free tree.
2024 msp
->ms_max_size
= metaslab_block_maxsize(msp
);
2027 * Segment-based weighting requires space map histogram support.
2029 if (zfs_metaslab_segment_weight_enabled
&&
2030 spa_feature_is_enabled(spa
, SPA_FEATURE_SPACEMAP_HISTOGRAM
) &&
2031 (msp
->ms_sm
== NULL
|| msp
->ms_sm
->sm_dbuf
->db_size
==
2032 sizeof (space_map_phys_t
))) {
2033 weight
= metaslab_segment_weight(msp
);
2035 weight
= metaslab_space_weight(msp
);
2041 metaslab_activate_allocator(metaslab_group_t
*mg
, metaslab_t
*msp
,
2042 int allocator
, uint64_t activation_weight
)
2045 * If we're activating for the claim code, we don't want to actually
2046 * set the metaslab up for a specific allocator.
2048 if (activation_weight
== METASLAB_WEIGHT_CLAIM
)
2050 metaslab_t
**arr
= (activation_weight
== METASLAB_WEIGHT_PRIMARY
?
2051 mg
->mg_primaries
: mg
->mg_secondaries
);
2053 ASSERT(MUTEX_HELD(&msp
->ms_lock
));
2054 mutex_enter(&mg
->mg_lock
);
2055 if (arr
[allocator
] != NULL
) {
2056 mutex_exit(&mg
->mg_lock
);
2060 arr
[allocator
] = msp
;
2061 ASSERT3S(msp
->ms_allocator
, ==, -1);
2062 msp
->ms_allocator
= allocator
;
2063 msp
->ms_primary
= (activation_weight
== METASLAB_WEIGHT_PRIMARY
);
2064 mutex_exit(&mg
->mg_lock
);
2070 metaslab_activate(metaslab_t
*msp
, int allocator
, uint64_t activation_weight
)
2072 ASSERT(MUTEX_HELD(&msp
->ms_lock
));
2074 if ((msp
->ms_weight
& METASLAB_ACTIVE_MASK
) == 0) {
2076 metaslab_load_wait(msp
);
2077 if (!msp
->ms_loaded
) {
2078 if ((error
= metaslab_load(msp
)) != 0) {
2079 metaslab_group_sort(msp
->ms_group
, msp
, 0);
2083 if ((msp
->ms_weight
& METASLAB_ACTIVE_MASK
) != 0) {
2085 * The metaslab was activated for another allocator
2086 * while we were waiting, we should reselect.
2090 if ((error
= metaslab_activate_allocator(msp
->ms_group
, msp
,
2091 allocator
, activation_weight
)) != 0) {
2095 msp
->ms_activation_weight
= msp
->ms_weight
;
2096 metaslab_group_sort(msp
->ms_group
, msp
,
2097 msp
->ms_weight
| activation_weight
);
2099 ASSERT(msp
->ms_loaded
);
2100 ASSERT(msp
->ms_weight
& METASLAB_ACTIVE_MASK
);
2106 metaslab_passivate_allocator(metaslab_group_t
*mg
, metaslab_t
*msp
,
2109 ASSERT(MUTEX_HELD(&msp
->ms_lock
));
2110 if (msp
->ms_weight
& METASLAB_WEIGHT_CLAIM
) {
2111 metaslab_group_sort(mg
, msp
, weight
);
2115 mutex_enter(&mg
->mg_lock
);
2116 ASSERT3P(msp
->ms_group
, ==, mg
);
2117 if (msp
->ms_primary
) {
2118 ASSERT3U(0, <=, msp
->ms_allocator
);
2119 ASSERT3U(msp
->ms_allocator
, <, mg
->mg_allocators
);
2120 ASSERT3P(mg
->mg_primaries
[msp
->ms_allocator
], ==, msp
);
2121 ASSERT(msp
->ms_weight
& METASLAB_WEIGHT_PRIMARY
);
2122 mg
->mg_primaries
[msp
->ms_allocator
] = NULL
;
2124 ASSERT(msp
->ms_weight
& METASLAB_WEIGHT_SECONDARY
);
2125 ASSERT3P(mg
->mg_secondaries
[msp
->ms_allocator
], ==, msp
);
2126 mg
->mg_secondaries
[msp
->ms_allocator
] = NULL
;
2128 msp
->ms_allocator
= -1;
2129 metaslab_group_sort_impl(mg
, msp
, weight
);
2130 mutex_exit(&mg
->mg_lock
);
2134 metaslab_passivate(metaslab_t
*msp
, uint64_t weight
)
2136 uint64_t size
= weight
& ~METASLAB_WEIGHT_TYPE
;
2139 * If size < SPA_MINBLOCKSIZE, then we will not allocate from
2140 * this metaslab again. In that case, it had better be empty,
2141 * or we would be leaving space on the table.
2143 ASSERT(size
>= SPA_MINBLOCKSIZE
||
2144 range_tree_is_empty(msp
->ms_allocatable
));
2145 ASSERT0(weight
& METASLAB_ACTIVE_MASK
);
2147 msp
->ms_activation_weight
= 0;
2148 metaslab_passivate_allocator(msp
->ms_group
, msp
, weight
);
2149 ASSERT((msp
->ms_weight
& METASLAB_ACTIVE_MASK
) == 0);
2153 * Segment-based metaslabs are activated once and remain active until
2154 * we either fail an allocation attempt (similar to space-based metaslabs)
2155 * or have exhausted the free space in zfs_metaslab_switch_threshold
2156 * buckets since the metaslab was activated. This function checks to see
2157 * if we've exhaused the zfs_metaslab_switch_threshold buckets in the
2158 * metaslab and passivates it proactively. This will allow us to select a
2159 * metaslabs with larger contiguous region if any remaining within this
2160 * metaslab group. If we're in sync pass > 1, then we continue using this
2161 * metaslab so that we don't dirty more block and cause more sync passes.
2164 metaslab_segment_may_passivate(metaslab_t
*msp
)
2166 spa_t
*spa
= msp
->ms_group
->mg_vd
->vdev_spa
;
2168 if (WEIGHT_IS_SPACEBASED(msp
->ms_weight
) || spa_sync_pass(spa
) > 1)
2172 * Since we are in the middle of a sync pass, the most accurate
2173 * information that is accessible to us is the in-core range tree
2174 * histogram; calculate the new weight based on that information.
2176 uint64_t weight
= metaslab_weight_from_range_tree(msp
);
2177 int activation_idx
= WEIGHT_GET_INDEX(msp
->ms_activation_weight
);
2178 int current_idx
= WEIGHT_GET_INDEX(weight
);
2180 if (current_idx
<= activation_idx
- zfs_metaslab_switch_threshold
)
2181 metaslab_passivate(msp
, weight
);
2185 metaslab_preload(void *arg
)
2187 metaslab_t
*msp
= arg
;
2188 spa_t
*spa
= msp
->ms_group
->mg_vd
->vdev_spa
;
2190 ASSERT(!MUTEX_HELD(&msp
->ms_group
->mg_lock
));
2192 mutex_enter(&msp
->ms_lock
);
2193 metaslab_load_wait(msp
);
2194 if (!msp
->ms_loaded
)
2195 (void) metaslab_load(msp
);
2196 msp
->ms_selected_txg
= spa_syncing_txg(spa
);
2197 mutex_exit(&msp
->ms_lock
);
2201 metaslab_group_preload(metaslab_group_t
*mg
)
2203 spa_t
*spa
= mg
->mg_vd
->vdev_spa
;
2205 avl_tree_t
*t
= &mg
->mg_metaslab_tree
;
2208 if (spa_shutting_down(spa
) || !metaslab_preload_enabled
) {
2209 taskq_wait(mg
->mg_taskq
);
2213 mutex_enter(&mg
->mg_lock
);
2216 * Load the next potential metaslabs
2218 for (msp
= avl_first(t
); msp
!= NULL
; msp
= AVL_NEXT(t
, msp
)) {
2219 ASSERT3P(msp
->ms_group
, ==, mg
);
2222 * We preload only the maximum number of metaslabs specified
2223 * by metaslab_preload_limit. If a metaslab is being forced
2224 * to condense then we preload it too. This will ensure
2225 * that force condensing happens in the next txg.
2227 if (++m
> metaslab_preload_limit
&& !msp
->ms_condense_wanted
) {
2231 VERIFY(taskq_dispatch(mg
->mg_taskq
, metaslab_preload
,
2232 msp
, TQ_SLEEP
) != (uintptr_t)NULL
);
2234 mutex_exit(&mg
->mg_lock
);
2238 * Determine if the space map's on-disk footprint is past our tolerance
2239 * for inefficiency. We would like to use the following criteria to make
2242 * 1. The size of the space map object should not dramatically increase as a
2243 * result of writing out the free space range tree.
2245 * 2. The minimal on-disk space map representation is zfs_condense_pct/100
2246 * times the size than the free space range tree representation
2247 * (i.e. zfs_condense_pct = 110 and in-core = 1MB, minimal = 1.1MB).
2249 * 3. The on-disk size of the space map should actually decrease.
2251 * Unfortunately, we cannot compute the on-disk size of the space map in this
2252 * context because we cannot accurately compute the effects of compression, etc.
2253 * Instead, we apply the heuristic described in the block comment for
2254 * zfs_metaslab_condense_block_threshold - we only condense if the space used
2255 * is greater than a threshold number of blocks.
2258 metaslab_should_condense(metaslab_t
*msp
)
2260 space_map_t
*sm
= msp
->ms_sm
;
2261 vdev_t
*vd
= msp
->ms_group
->mg_vd
;
2262 uint64_t vdev_blocksize
= 1 << vd
->vdev_ashift
;
2263 uint64_t current_txg
= spa_syncing_txg(vd
->vdev_spa
);
2265 ASSERT(MUTEX_HELD(&msp
->ms_lock
));
2266 ASSERT(msp
->ms_loaded
);
2269 * Allocations and frees in early passes are generally more space
2270 * efficient (in terms of blocks described in space map entries)
2271 * than the ones in later passes (e.g. we don't compress after
2272 * sync pass 5) and condensing a metaslab multiple times in a txg
2273 * could degrade performance.
2275 * Thus we prefer condensing each metaslab at most once every txg at
2276 * the earliest sync pass possible. If a metaslab is eligible for
2277 * condensing again after being considered for condensing within the
2278 * same txg, it will hopefully be dirty in the next txg where it will
2279 * be condensed at an earlier pass.
2281 if (msp
->ms_condense_checked_txg
== current_txg
)
2283 msp
->ms_condense_checked_txg
= current_txg
;
2286 * We always condense metaslabs that are empty and metaslabs for
2287 * which a condense request has been made.
2289 if (avl_is_empty(&msp
->ms_allocatable_by_size
) ||
2290 msp
->ms_condense_wanted
)
2293 uint64_t object_size
= space_map_length(msp
->ms_sm
);
2294 uint64_t optimal_size
= space_map_estimate_optimal_size(sm
,
2295 msp
->ms_allocatable
, SM_NO_VDEVID
);
2297 dmu_object_info_t doi
;
2298 dmu_object_info_from_db(sm
->sm_dbuf
, &doi
);
2299 uint64_t record_size
= MAX(doi
.doi_data_block_size
, vdev_blocksize
);
2301 return (object_size
>= (optimal_size
* zfs_condense_pct
/ 100) &&
2302 object_size
> zfs_metaslab_condense_block_threshold
* record_size
);
2306 * Condense the on-disk space map representation to its minimized form.
2307 * The minimized form consists of a small number of allocations followed by
2308 * the entries of the free range tree.
2311 metaslab_condense(metaslab_t
*msp
, uint64_t txg
, dmu_tx_t
*tx
)
2313 range_tree_t
*condense_tree
;
2314 space_map_t
*sm
= msp
->ms_sm
;
2316 ASSERT(MUTEX_HELD(&msp
->ms_lock
));
2317 ASSERT(msp
->ms_loaded
);
2319 zfs_dbgmsg("condensing: txg %llu, msp[%llu] %p, vdev id %llu, "
2320 "spa %s, smp size %llu, segments %lu, forcing condense=%s", txg
,
2321 msp
->ms_id
, msp
, msp
->ms_group
->mg_vd
->vdev_id
,
2322 msp
->ms_group
->mg_vd
->vdev_spa
->spa_name
,
2323 space_map_length(msp
->ms_sm
),
2324 avl_numnodes(&msp
->ms_allocatable
->rt_root
),
2325 msp
->ms_condense_wanted
? "TRUE" : "FALSE");
2327 msp
->ms_condense_wanted
= B_FALSE
;
2330 * Create an range tree that is 100% allocated. We remove segments
2331 * that have been freed in this txg, any deferred frees that exist,
2332 * and any allocation in the future. Removing segments should be
2333 * a relatively inexpensive operation since we expect these trees to
2334 * have a small number of nodes.
2336 condense_tree
= range_tree_create(NULL
, NULL
);
2337 range_tree_add(condense_tree
, msp
->ms_start
, msp
->ms_size
);
2339 range_tree_walk(msp
->ms_freeing
, range_tree_remove
, condense_tree
);
2340 range_tree_walk(msp
->ms_freed
, range_tree_remove
, condense_tree
);
2342 for (int t
= 0; t
< TXG_DEFER_SIZE
; t
++) {
2343 range_tree_walk(msp
->ms_defer
[t
],
2344 range_tree_remove
, condense_tree
);
2347 for (int t
= 1; t
< TXG_CONCURRENT_STATES
; t
++) {
2348 range_tree_walk(msp
->ms_allocating
[(txg
+ t
) & TXG_MASK
],
2349 range_tree_remove
, condense_tree
);
2353 * We're about to drop the metaslab's lock thus allowing
2354 * other consumers to change it's content. Set the
2355 * metaslab's ms_condensing flag to ensure that
2356 * allocations on this metaslab do not occur while we're
2357 * in the middle of committing it to disk. This is only critical
2358 * for ms_allocatable as all other range trees use per txg
2359 * views of their content.
2361 msp
->ms_condensing
= B_TRUE
;
2363 mutex_exit(&msp
->ms_lock
);
2364 space_map_truncate(sm
, zfs_metaslab_sm_blksz
, tx
);
2367 * While we would ideally like to create a space map representation
2368 * that consists only of allocation records, doing so can be
2369 * prohibitively expensive because the in-core free tree can be
2370 * large, and therefore computationally expensive to subtract
2371 * from the condense_tree. Instead we sync out two trees, a cheap
2372 * allocation only tree followed by the in-core free tree. While not
2373 * optimal, this is typically close to optimal, and much cheaper to
2376 space_map_write(sm
, condense_tree
, SM_ALLOC
, SM_NO_VDEVID
, tx
);
2377 range_tree_vacate(condense_tree
, NULL
, NULL
);
2378 range_tree_destroy(condense_tree
);
2380 space_map_write(sm
, msp
->ms_allocatable
, SM_FREE
, SM_NO_VDEVID
, tx
);
2381 mutex_enter(&msp
->ms_lock
);
2382 msp
->ms_condensing
= B_FALSE
;
2386 * Write a metaslab to disk in the context of the specified transaction group.
2389 metaslab_sync(metaslab_t
*msp
, uint64_t txg
)
2391 metaslab_group_t
*mg
= msp
->ms_group
;
2392 vdev_t
*vd
= mg
->mg_vd
;
2393 spa_t
*spa
= vd
->vdev_spa
;
2394 objset_t
*mos
= spa_meta_objset(spa
);
2395 range_tree_t
*alloctree
= msp
->ms_allocating
[txg
& TXG_MASK
];
2397 uint64_t object
= space_map_object(msp
->ms_sm
);
2399 ASSERT(!vd
->vdev_ishole
);
2402 * This metaslab has just been added so there's no work to do now.
2404 if (msp
->ms_freeing
== NULL
) {
2405 ASSERT3P(alloctree
, ==, NULL
);
2409 ASSERT3P(alloctree
, !=, NULL
);
2410 ASSERT3P(msp
->ms_freeing
, !=, NULL
);
2411 ASSERT3P(msp
->ms_freed
, !=, NULL
);
2412 ASSERT3P(msp
->ms_checkpointing
, !=, NULL
);
2415 * Normally, we don't want to process a metaslab if there are no
2416 * allocations or frees to perform. However, if the metaslab is being
2417 * forced to condense and it's loaded, we need to let it through.
2419 if (range_tree_is_empty(alloctree
) &&
2420 range_tree_is_empty(msp
->ms_freeing
) &&
2421 range_tree_is_empty(msp
->ms_checkpointing
) &&
2422 !(msp
->ms_loaded
&& msp
->ms_condense_wanted
))
2426 VERIFY(txg
<= spa_final_dirty_txg(spa
));
2429 * The only state that can actually be changing concurrently with
2430 * metaslab_sync() is the metaslab's ms_allocatable. No other
2431 * thread can be modifying this txg's alloc, freeing,
2432 * freed, or space_map_phys_t. We drop ms_lock whenever we
2433 * could call into the DMU, because the DMU can call down to us
2434 * (e.g. via zio_free()) at any time.
2436 * The spa_vdev_remove_thread() can be reading metaslab state
2437 * concurrently, and it is locked out by the ms_sync_lock. Note
2438 * that the ms_lock is insufficient for this, because it is dropped
2439 * by space_map_write().
2441 tx
= dmu_tx_create_assigned(spa_get_dsl(spa
), txg
);
2443 if (msp
->ms_sm
== NULL
) {
2444 uint64_t new_object
;
2446 new_object
= space_map_alloc(mos
, zfs_metaslab_sm_blksz
, tx
);
2447 VERIFY3U(new_object
, !=, 0);
2449 VERIFY0(space_map_open(&msp
->ms_sm
, mos
, new_object
,
2450 msp
->ms_start
, msp
->ms_size
, vd
->vdev_ashift
));
2451 ASSERT(msp
->ms_sm
!= NULL
);
2454 if (!range_tree_is_empty(msp
->ms_checkpointing
) &&
2455 vd
->vdev_checkpoint_sm
== NULL
) {
2456 ASSERT(spa_has_checkpoint(spa
));
2458 uint64_t new_object
= space_map_alloc(mos
,
2459 vdev_standard_sm_blksz
, tx
);
2460 VERIFY3U(new_object
, !=, 0);
2462 VERIFY0(space_map_open(&vd
->vdev_checkpoint_sm
,
2463 mos
, new_object
, 0, vd
->vdev_asize
, vd
->vdev_ashift
));
2464 ASSERT3P(vd
->vdev_checkpoint_sm
, !=, NULL
);
2467 * We save the space map object as an entry in vdev_top_zap
2468 * so it can be retrieved when the pool is reopened after an
2469 * export or through zdb.
2471 VERIFY0(zap_add(vd
->vdev_spa
->spa_meta_objset
,
2472 vd
->vdev_top_zap
, VDEV_TOP_ZAP_POOL_CHECKPOINT_SM
,
2473 sizeof (new_object
), 1, &new_object
, tx
));
2476 mutex_enter(&msp
->ms_sync_lock
);
2477 mutex_enter(&msp
->ms_lock
);
2480 * Note: metaslab_condense() clears the space map's histogram.
2481 * Therefore we must verify and remove this histogram before
2484 metaslab_group_histogram_verify(mg
);
2485 metaslab_class_histogram_verify(mg
->mg_class
);
2486 metaslab_group_histogram_remove(mg
, msp
);
2488 if (msp
->ms_loaded
&& metaslab_should_condense(msp
)) {
2489 metaslab_condense(msp
, txg
, tx
);
2491 mutex_exit(&msp
->ms_lock
);
2492 space_map_write(msp
->ms_sm
, alloctree
, SM_ALLOC
,
2494 space_map_write(msp
->ms_sm
, msp
->ms_freeing
, SM_FREE
,
2496 mutex_enter(&msp
->ms_lock
);
2499 if (!range_tree_is_empty(msp
->ms_checkpointing
)) {
2500 ASSERT(spa_has_checkpoint(spa
));
2501 ASSERT3P(vd
->vdev_checkpoint_sm
, !=, NULL
);
2504 * Since we are doing writes to disk and the ms_checkpointing
2505 * tree won't be changing during that time, we drop the
2506 * ms_lock while writing to the checkpoint space map.
2508 mutex_exit(&msp
->ms_lock
);
2509 space_map_write(vd
->vdev_checkpoint_sm
,
2510 msp
->ms_checkpointing
, SM_FREE
, SM_NO_VDEVID
, tx
);
2511 mutex_enter(&msp
->ms_lock
);
2512 space_map_update(vd
->vdev_checkpoint_sm
);
2514 spa
->spa_checkpoint_info
.sci_dspace
+=
2515 range_tree_space(msp
->ms_checkpointing
);
2516 vd
->vdev_stat
.vs_checkpoint_space
+=
2517 range_tree_space(msp
->ms_checkpointing
);
2518 ASSERT3U(vd
->vdev_stat
.vs_checkpoint_space
, ==,
2519 -vd
->vdev_checkpoint_sm
->sm_alloc
);
2521 range_tree_vacate(msp
->ms_checkpointing
, NULL
, NULL
);
2524 if (msp
->ms_loaded
) {
2526 * When the space map is loaded, we have an accurate
2527 * histogram in the range tree. This gives us an opportunity
2528 * to bring the space map's histogram up-to-date so we clear
2529 * it first before updating it.
2531 space_map_histogram_clear(msp
->ms_sm
);
2532 space_map_histogram_add(msp
->ms_sm
, msp
->ms_allocatable
, tx
);
2535 * Since we've cleared the histogram we need to add back
2536 * any free space that has already been processed, plus
2537 * any deferred space. This allows the on-disk histogram
2538 * to accurately reflect all free space even if some space
2539 * is not yet available for allocation (i.e. deferred).
2541 space_map_histogram_add(msp
->ms_sm
, msp
->ms_freed
, tx
);
2544 * Add back any deferred free space that has not been
2545 * added back into the in-core free tree yet. This will
2546 * ensure that we don't end up with a space map histogram
2547 * that is completely empty unless the metaslab is fully
2550 for (int t
= 0; t
< TXG_DEFER_SIZE
; t
++) {
2551 space_map_histogram_add(msp
->ms_sm
,
2552 msp
->ms_defer
[t
], tx
);
2557 * Always add the free space from this sync pass to the space
2558 * map histogram. We want to make sure that the on-disk histogram
2559 * accounts for all free space. If the space map is not loaded,
2560 * then we will lose some accuracy but will correct it the next
2561 * time we load the space map.
2563 space_map_histogram_add(msp
->ms_sm
, msp
->ms_freeing
, tx
);
2565 metaslab_group_histogram_add(mg
, msp
);
2566 metaslab_group_histogram_verify(mg
);
2567 metaslab_class_histogram_verify(mg
->mg_class
);
2570 * For sync pass 1, we avoid traversing this txg's free range tree
2571 * and instead will just swap the pointers for freeing and
2572 * freed. We can safely do this since the freed_tree is
2573 * guaranteed to be empty on the initial pass.
2575 if (spa_sync_pass(spa
) == 1) {
2576 range_tree_swap(&msp
->ms_freeing
, &msp
->ms_freed
);
2578 range_tree_vacate(msp
->ms_freeing
,
2579 range_tree_add
, msp
->ms_freed
);
2581 range_tree_vacate(alloctree
, NULL
, NULL
);
2583 ASSERT0(range_tree_space(msp
->ms_allocating
[txg
& TXG_MASK
]));
2584 ASSERT0(range_tree_space(msp
->ms_allocating
[TXG_CLEAN(txg
)
2586 ASSERT0(range_tree_space(msp
->ms_freeing
));
2587 ASSERT0(range_tree_space(msp
->ms_checkpointing
));
2589 mutex_exit(&msp
->ms_lock
);
2591 if (object
!= space_map_object(msp
->ms_sm
)) {
2592 object
= space_map_object(msp
->ms_sm
);
2593 dmu_write(mos
, vd
->vdev_ms_array
, sizeof (uint64_t) *
2594 msp
->ms_id
, sizeof (uint64_t), &object
, tx
);
2596 mutex_exit(&msp
->ms_sync_lock
);
2601 * Called after a transaction group has completely synced to mark
2602 * all of the metaslab's free space as usable.
2605 metaslab_sync_done(metaslab_t
*msp
, uint64_t txg
)
2607 metaslab_group_t
*mg
= msp
->ms_group
;
2608 vdev_t
*vd
= mg
->mg_vd
;
2609 spa_t
*spa
= vd
->vdev_spa
;
2610 range_tree_t
**defer_tree
;
2611 int64_t alloc_delta
, defer_delta
;
2612 boolean_t defer_allowed
= B_TRUE
;
2614 ASSERT(!vd
->vdev_ishole
);
2616 mutex_enter(&msp
->ms_lock
);
2619 * If this metaslab is just becoming available, initialize its
2620 * range trees and add its capacity to the vdev.
2622 if (msp
->ms_freed
== NULL
) {
2623 for (int t
= 0; t
< TXG_SIZE
; t
++) {
2624 ASSERT(msp
->ms_allocating
[t
] == NULL
);
2626 msp
->ms_allocating
[t
] = range_tree_create(NULL
, NULL
);
2629 ASSERT3P(msp
->ms_freeing
, ==, NULL
);
2630 msp
->ms_freeing
= range_tree_create(NULL
, NULL
);
2632 ASSERT3P(msp
->ms_freed
, ==, NULL
);
2633 msp
->ms_freed
= range_tree_create(NULL
, NULL
);
2635 for (int t
= 0; t
< TXG_DEFER_SIZE
; t
++) {
2636 ASSERT(msp
->ms_defer
[t
] == NULL
);
2638 msp
->ms_defer
[t
] = range_tree_create(NULL
, NULL
);
2641 ASSERT3P(msp
->ms_checkpointing
, ==, NULL
);
2642 msp
->ms_checkpointing
= range_tree_create(NULL
, NULL
);
2644 vdev_space_update(vd
, 0, 0, msp
->ms_size
);
2646 ASSERT0(range_tree_space(msp
->ms_freeing
));
2647 ASSERT0(range_tree_space(msp
->ms_checkpointing
));
2649 defer_tree
= &msp
->ms_defer
[txg
% TXG_DEFER_SIZE
];
2651 uint64_t free_space
= metaslab_class_get_space(spa_normal_class(spa
)) -
2652 metaslab_class_get_alloc(spa_normal_class(spa
));
2653 if (free_space
<= spa_get_slop_space(spa
) || vd
->vdev_removing
) {
2654 defer_allowed
= B_FALSE
;
2658 alloc_delta
= space_map_alloc_delta(msp
->ms_sm
);
2659 if (defer_allowed
) {
2660 defer_delta
= range_tree_space(msp
->ms_freed
) -
2661 range_tree_space(*defer_tree
);
2663 defer_delta
-= range_tree_space(*defer_tree
);
2666 vdev_space_update(vd
, alloc_delta
+ defer_delta
, defer_delta
, 0);
2669 * If there's a metaslab_load() in progress, wait for it to complete
2670 * so that we have a consistent view of the in-core space map.
2672 metaslab_load_wait(msp
);
2675 * Move the frees from the defer_tree back to the free
2676 * range tree (if it's loaded). Swap the freed_tree and
2677 * the defer_tree -- this is safe to do because we've
2678 * just emptied out the defer_tree.
2680 range_tree_vacate(*defer_tree
,
2681 msp
->ms_loaded
? range_tree_add
: NULL
, msp
->ms_allocatable
);
2682 if (defer_allowed
) {
2683 range_tree_swap(&msp
->ms_freed
, defer_tree
);
2685 range_tree_vacate(msp
->ms_freed
,
2686 msp
->ms_loaded
? range_tree_add
: NULL
,
2687 msp
->ms_allocatable
);
2689 space_map_update(msp
->ms_sm
);
2691 msp
->ms_deferspace
+= defer_delta
;
2692 ASSERT3S(msp
->ms_deferspace
, >=, 0);
2693 ASSERT3S(msp
->ms_deferspace
, <=, msp
->ms_size
);
2694 if (msp
->ms_deferspace
!= 0) {
2696 * Keep syncing this metaslab until all deferred frees
2697 * are back in circulation.
2699 vdev_dirty(vd
, VDD_METASLAB
, msp
, txg
+ 1);
2703 msp
->ms_new
= B_FALSE
;
2704 mutex_enter(&mg
->mg_lock
);
2706 mutex_exit(&mg
->mg_lock
);
2709 * Calculate the new weights before unloading any metaslabs.
2710 * This will give us the most accurate weighting.
2712 metaslab_group_sort(mg
, msp
, metaslab_weight(msp
) |
2713 (msp
->ms_weight
& METASLAB_ACTIVE_MASK
));
2716 * If the metaslab is loaded and we've not tried to load or allocate
2717 * from it in 'metaslab_unload_delay' txgs, then unload it.
2719 if (msp
->ms_loaded
&&
2720 msp
->ms_selected_txg
+ metaslab_unload_delay
< txg
) {
2721 for (int t
= 1; t
< TXG_CONCURRENT_STATES
; t
++) {
2722 VERIFY0(range_tree_space(
2723 msp
->ms_allocating
[(txg
+ t
) & TXG_MASK
]));
2725 if (msp
->ms_allocator
!= -1) {
2726 metaslab_passivate(msp
, msp
->ms_weight
&
2727 ~METASLAB_ACTIVE_MASK
);
2730 if (!metaslab_debug_unload
)
2731 metaslab_unload(msp
);
2734 ASSERT0(range_tree_space(msp
->ms_allocating
[txg
& TXG_MASK
]));
2735 ASSERT0(range_tree_space(msp
->ms_freeing
));
2736 ASSERT0(range_tree_space(msp
->ms_freed
));
2737 ASSERT0(range_tree_space(msp
->ms_checkpointing
));
2739 mutex_exit(&msp
->ms_lock
);
2743 metaslab_sync_reassess(metaslab_group_t
*mg
)
2745 spa_t
*spa
= mg
->mg_class
->mc_spa
;
2747 spa_config_enter(spa
, SCL_ALLOC
, FTAG
, RW_READER
);
2748 metaslab_group_alloc_update(mg
);
2749 mg
->mg_fragmentation
= metaslab_group_fragmentation(mg
);
2752 * Preload the next potential metaslabs but only on active
2753 * metaslab groups. We can get into a state where the metaslab
2754 * is no longer active since we dirty metaslabs as we remove a
2755 * a device, thus potentially making the metaslab group eligible
2758 if (mg
->mg_activation_count
> 0) {
2759 metaslab_group_preload(mg
);
2761 spa_config_exit(spa
, SCL_ALLOC
, FTAG
);
2765 metaslab_distance(metaslab_t
*msp
, dva_t
*dva
)
2767 uint64_t ms_shift
= msp
->ms_group
->mg_vd
->vdev_ms_shift
;
2768 uint64_t offset
= DVA_GET_OFFSET(dva
) >> ms_shift
;
2769 uint64_t start
= msp
->ms_id
;
2771 if (msp
->ms_group
->mg_vd
->vdev_id
!= DVA_GET_VDEV(dva
))
2772 return (1ULL << 63);
2775 return ((start
- offset
) << ms_shift
);
2777 return ((offset
- start
) << ms_shift
);
2782 * ==========================================================================
2783 * Metaslab allocation tracing facility
2784 * ==========================================================================
2786 kstat_t
*metaslab_trace_ksp
;
2787 kstat_named_t metaslab_trace_over_limit
;
2790 metaslab_alloc_trace_init(void)
2792 ASSERT(metaslab_alloc_trace_cache
== NULL
);
2793 metaslab_alloc_trace_cache
= kmem_cache_create(
2794 "metaslab_alloc_trace_cache", sizeof (metaslab_alloc_trace_t
),
2795 0, NULL
, NULL
, NULL
, NULL
, NULL
, 0);
2796 metaslab_trace_ksp
= kstat_create("zfs", 0, "metaslab_trace_stats",
2797 "misc", KSTAT_TYPE_NAMED
, 1, KSTAT_FLAG_VIRTUAL
);
2798 if (metaslab_trace_ksp
!= NULL
) {
2799 metaslab_trace_ksp
->ks_data
= &metaslab_trace_over_limit
;
2800 kstat_named_init(&metaslab_trace_over_limit
,
2801 "metaslab_trace_over_limit", KSTAT_DATA_UINT64
);
2802 kstat_install(metaslab_trace_ksp
);
2807 metaslab_alloc_trace_fini(void)
2809 if (metaslab_trace_ksp
!= NULL
) {
2810 kstat_delete(metaslab_trace_ksp
);
2811 metaslab_trace_ksp
= NULL
;
2813 kmem_cache_destroy(metaslab_alloc_trace_cache
);
2814 metaslab_alloc_trace_cache
= NULL
;
2818 * Add an allocation trace element to the allocation tracing list.
2821 metaslab_trace_add(zio_alloc_list_t
*zal
, metaslab_group_t
*mg
,
2822 metaslab_t
*msp
, uint64_t psize
, uint32_t dva_id
, uint64_t offset
,
2825 if (!metaslab_trace_enabled
)
2829 * When the tracing list reaches its maximum we remove
2830 * the second element in the list before adding a new one.
2831 * By removing the second element we preserve the original
2832 * entry as a clue to what allocations steps have already been
2835 if (zal
->zal_size
== metaslab_trace_max_entries
) {
2836 metaslab_alloc_trace_t
*mat_next
;
2838 panic("too many entries in allocation list");
2840 atomic_inc_64(&metaslab_trace_over_limit
.value
.ui64
);
2842 mat_next
= list_next(&zal
->zal_list
, list_head(&zal
->zal_list
));
2843 list_remove(&zal
->zal_list
, mat_next
);
2844 kmem_cache_free(metaslab_alloc_trace_cache
, mat_next
);
2847 metaslab_alloc_trace_t
*mat
=
2848 kmem_cache_alloc(metaslab_alloc_trace_cache
, KM_SLEEP
);
2849 list_link_init(&mat
->mat_list_node
);
2852 mat
->mat_size
= psize
;
2853 mat
->mat_dva_id
= dva_id
;
2854 mat
->mat_offset
= offset
;
2855 mat
->mat_weight
= 0;
2856 mat
->mat_allocator
= allocator
;
2859 mat
->mat_weight
= msp
->ms_weight
;
2862 * The list is part of the zio so locking is not required. Only
2863 * a single thread will perform allocations for a given zio.
2865 list_insert_tail(&zal
->zal_list
, mat
);
2868 ASSERT3U(zal
->zal_size
, <=, metaslab_trace_max_entries
);
2872 metaslab_trace_init(zio_alloc_list_t
*zal
)
2874 list_create(&zal
->zal_list
, sizeof (metaslab_alloc_trace_t
),
2875 offsetof(metaslab_alloc_trace_t
, mat_list_node
));
2880 metaslab_trace_fini(zio_alloc_list_t
*zal
)
2882 metaslab_alloc_trace_t
*mat
;
2884 while ((mat
= list_remove_head(&zal
->zal_list
)) != NULL
)
2885 kmem_cache_free(metaslab_alloc_trace_cache
, mat
);
2886 list_destroy(&zal
->zal_list
);
2891 * ==========================================================================
2892 * Metaslab block operations
2893 * ==========================================================================
2897 metaslab_group_alloc_increment(spa_t
*spa
, uint64_t vdev
, void *tag
, int flags
,
2900 if (!(flags
& METASLAB_ASYNC_ALLOC
) ||
2901 (flags
& METASLAB_DONT_THROTTLE
))
2904 metaslab_group_t
*mg
= vdev_lookup_top(spa
, vdev
)->vdev_mg
;
2905 if (!mg
->mg_class
->mc_alloc_throttle_enabled
)
2908 (void) refcount_add(&mg
->mg_alloc_queue_depth
[allocator
], tag
);
2912 metaslab_group_increment_qdepth(metaslab_group_t
*mg
, int allocator
)
2914 uint64_t max
= mg
->mg_max_alloc_queue_depth
;
2915 uint64_t cur
= mg
->mg_cur_max_alloc_queue_depth
[allocator
];
2917 if (atomic_cas_64(&mg
->mg_cur_max_alloc_queue_depth
[allocator
],
2918 cur
, cur
+ 1) == cur
) {
2920 &mg
->mg_class
->mc_alloc_max_slots
[allocator
]);
2923 cur
= mg
->mg_cur_max_alloc_queue_depth
[allocator
];
2928 metaslab_group_alloc_decrement(spa_t
*spa
, uint64_t vdev
, void *tag
, int flags
,
2929 int allocator
, boolean_t io_complete
)
2931 if (!(flags
& METASLAB_ASYNC_ALLOC
) ||
2932 (flags
& METASLAB_DONT_THROTTLE
))
2935 metaslab_group_t
*mg
= vdev_lookup_top(spa
, vdev
)->vdev_mg
;
2936 if (!mg
->mg_class
->mc_alloc_throttle_enabled
)
2939 (void) refcount_remove(&mg
->mg_alloc_queue_depth
[allocator
], tag
);
2941 metaslab_group_increment_qdepth(mg
, allocator
);
2945 metaslab_group_alloc_verify(spa_t
*spa
, const blkptr_t
*bp
, void *tag
,
2949 const dva_t
*dva
= bp
->blk_dva
;
2950 int ndvas
= BP_GET_NDVAS(bp
);
2952 for (int d
= 0; d
< ndvas
; d
++) {
2953 uint64_t vdev
= DVA_GET_VDEV(&dva
[d
]);
2954 metaslab_group_t
*mg
= vdev_lookup_top(spa
, vdev
)->vdev_mg
;
2955 VERIFY(refcount_not_held(&mg
->mg_alloc_queue_depth
[allocator
],
2962 metaslab_block_alloc(metaslab_t
*msp
, uint64_t size
, uint64_t txg
)
2965 range_tree_t
*rt
= msp
->ms_allocatable
;
2966 metaslab_class_t
*mc
= msp
->ms_group
->mg_class
;
2968 VERIFY(!msp
->ms_condensing
);
2970 start
= mc
->mc_ops
->msop_alloc(msp
, size
);
2971 if (start
!= -1ULL) {
2972 metaslab_group_t
*mg
= msp
->ms_group
;
2973 vdev_t
*vd
= mg
->mg_vd
;
2975 VERIFY0(P2PHASE(start
, 1ULL << vd
->vdev_ashift
));
2976 VERIFY0(P2PHASE(size
, 1ULL << vd
->vdev_ashift
));
2977 VERIFY3U(range_tree_space(rt
) - size
, <=, msp
->ms_size
);
2978 range_tree_remove(rt
, start
, size
);
2980 if (range_tree_is_empty(msp
->ms_allocating
[txg
& TXG_MASK
]))
2981 vdev_dirty(mg
->mg_vd
, VDD_METASLAB
, msp
, txg
);
2983 range_tree_add(msp
->ms_allocating
[txg
& TXG_MASK
], start
, size
);
2985 /* Track the last successful allocation */
2986 msp
->ms_alloc_txg
= txg
;
2987 metaslab_verify_space(msp
, txg
);
2991 * Now that we've attempted the allocation we need to update the
2992 * metaslab's maximum block size since it may have changed.
2994 msp
->ms_max_size
= metaslab_block_maxsize(msp
);
2999 * Find the metaslab with the highest weight that is less than what we've
3000 * already tried. In the common case, this means that we will examine each
3001 * metaslab at most once. Note that concurrent callers could reorder metaslabs
3002 * by activation/passivation once we have dropped the mg_lock. If a metaslab is
3003 * activated by another thread, and we fail to allocate from the metaslab we
3004 * have selected, we may not try the newly-activated metaslab, and instead
3005 * activate another metaslab. This is not optimal, but generally does not cause
3006 * any problems (a possible exception being if every metaslab is completely full
3007 * except for the the newly-activated metaslab which we fail to examine).
3010 find_valid_metaslab(metaslab_group_t
*mg
, uint64_t activation_weight
,
3011 dva_t
*dva
, int d
, uint64_t min_distance
, uint64_t asize
, int allocator
,
3012 zio_alloc_list_t
*zal
, metaslab_t
*search
, boolean_t
*was_active
)
3015 avl_tree_t
*t
= &mg
->mg_metaslab_tree
;
3016 metaslab_t
*msp
= avl_find(t
, search
, &idx
);
3018 msp
= avl_nearest(t
, idx
, AVL_AFTER
);
3020 for (; msp
!= NULL
; msp
= AVL_NEXT(t
, msp
)) {
3022 if (!metaslab_should_allocate(msp
, asize
)) {
3023 metaslab_trace_add(zal
, mg
, msp
, asize
, d
,
3024 TRACE_TOO_SMALL
, allocator
);
3029 * If the selected metaslab is condensing, skip it.
3031 if (msp
->ms_condensing
)
3034 *was_active
= msp
->ms_allocator
!= -1;
3036 * If we're activating as primary, this is our first allocation
3037 * from this disk, so we don't need to check how close we are.
3038 * If the metaslab under consideration was already active,
3039 * we're getting desperate enough to steal another allocator's
3040 * metaslab, so we still don't care about distances.
3042 if (activation_weight
== METASLAB_WEIGHT_PRIMARY
|| *was_active
)
3045 uint64_t target_distance
= min_distance
3046 + (space_map_allocated(msp
->ms_sm
) != 0 ? 0 :
3049 for (i
= 0; i
< d
; i
++) {
3050 if (metaslab_distance(msp
, &dva
[i
]) < target_distance
)
3058 search
->ms_weight
= msp
->ms_weight
;
3059 search
->ms_start
= msp
->ms_start
+ 1;
3060 search
->ms_allocator
= msp
->ms_allocator
;
3061 search
->ms_primary
= msp
->ms_primary
;
3068 metaslab_group_alloc_normal(metaslab_group_t
*mg
, zio_alloc_list_t
*zal
,
3069 uint64_t asize
, uint64_t txg
, uint64_t min_distance
, dva_t
*dva
, int d
,
3072 metaslab_t
*msp
= NULL
;
3073 uint64_t offset
= -1ULL;
3074 uint64_t activation_weight
;
3075 boolean_t tertiary
= B_FALSE
;
3077 activation_weight
= METASLAB_WEIGHT_PRIMARY
;
3078 for (int i
= 0; i
< d
; i
++) {
3079 if (activation_weight
== METASLAB_WEIGHT_PRIMARY
&&
3080 DVA_GET_VDEV(&dva
[i
]) == mg
->mg_vd
->vdev_id
) {
3081 activation_weight
= METASLAB_WEIGHT_SECONDARY
;
3082 } else if (activation_weight
== METASLAB_WEIGHT_SECONDARY
&&
3083 DVA_GET_VDEV(&dva
[i
]) == mg
->mg_vd
->vdev_id
) {
3090 * If we don't have enough metaslabs active to fill the entire array, we
3091 * just use the 0th slot.
3093 if (mg
->mg_ms_ready
< mg
->mg_allocators
* 2) {
3098 ASSERT3U(mg
->mg_vd
->vdev_ms_count
, >=, 2);
3100 metaslab_t
*search
= kmem_alloc(sizeof (*search
), KM_SLEEP
);
3101 search
->ms_weight
= UINT64_MAX
;
3102 search
->ms_start
= 0;
3104 * At the end of the metaslab tree are the already-active metaslabs,
3105 * first the primaries, then the secondaries. When we resume searching
3106 * through the tree, we need to consider ms_allocator and ms_primary so
3107 * we start in the location right after where we left off, and don't
3108 * accidentally loop forever considering the same metaslabs.
3110 search
->ms_allocator
= -1;
3111 search
->ms_primary
= B_TRUE
;
3113 boolean_t was_active
= B_FALSE
;
3115 mutex_enter(&mg
->mg_lock
);
3117 if (activation_weight
== METASLAB_WEIGHT_PRIMARY
&&
3118 mg
->mg_primaries
[allocator
] != NULL
) {
3119 msp
= mg
->mg_primaries
[allocator
];
3120 was_active
= B_TRUE
;
3121 } else if (activation_weight
== METASLAB_WEIGHT_SECONDARY
&&
3122 mg
->mg_secondaries
[allocator
] != NULL
&& !tertiary
) {
3123 msp
= mg
->mg_secondaries
[allocator
];
3124 was_active
= B_TRUE
;
3126 msp
= find_valid_metaslab(mg
, activation_weight
, dva
, d
,
3127 min_distance
, asize
, allocator
, zal
, search
,
3131 mutex_exit(&mg
->mg_lock
);
3133 kmem_free(search
, sizeof (*search
));
3137 mutex_enter(&msp
->ms_lock
);
3139 * Ensure that the metaslab we have selected is still
3140 * capable of handling our request. It's possible that
3141 * another thread may have changed the weight while we
3142 * were blocked on the metaslab lock. We check the
3143 * active status first to see if we need to reselect
3146 if (was_active
&& !(msp
->ms_weight
& METASLAB_ACTIVE_MASK
)) {
3147 mutex_exit(&msp
->ms_lock
);
3152 * If the metaslab is freshly activated for an allocator that
3153 * isn't the one we're allocating from, or if it's a primary and
3154 * we're seeking a secondary (or vice versa), we go back and
3155 * select a new metaslab.
3157 if (!was_active
&& (msp
->ms_weight
& METASLAB_ACTIVE_MASK
) &&
3158 (msp
->ms_allocator
!= -1) &&
3159 (msp
->ms_allocator
!= allocator
|| ((activation_weight
==
3160 METASLAB_WEIGHT_PRIMARY
) != msp
->ms_primary
))) {
3161 mutex_exit(&msp
->ms_lock
);
3165 if (msp
->ms_weight
& METASLAB_WEIGHT_CLAIM
) {
3166 metaslab_passivate(msp
, msp
->ms_weight
&
3167 ~METASLAB_WEIGHT_CLAIM
);
3168 mutex_exit(&msp
->ms_lock
);
3172 if (metaslab_activate(msp
, allocator
, activation_weight
) != 0) {
3173 mutex_exit(&msp
->ms_lock
);
3177 msp
->ms_selected_txg
= txg
;
3180 * Now that we have the lock, recheck to see if we should
3181 * continue to use this metaslab for this allocation. The
3182 * the metaslab is now loaded so metaslab_should_allocate() can
3183 * accurately determine if the allocation attempt should
3186 if (!metaslab_should_allocate(msp
, asize
)) {
3187 /* Passivate this metaslab and select a new one. */
3188 metaslab_trace_add(zal
, mg
, msp
, asize
, d
,
3189 TRACE_TOO_SMALL
, allocator
);
3194 * If this metaslab is currently condensing then pick again as
3195 * we can't manipulate this metaslab until it's committed
3198 if (msp
->ms_condensing
) {
3199 metaslab_trace_add(zal
, mg
, msp
, asize
, d
,
3200 TRACE_CONDENSING
, allocator
);
3201 metaslab_passivate(msp
, msp
->ms_weight
&
3202 ~METASLAB_ACTIVE_MASK
);
3203 mutex_exit(&msp
->ms_lock
);
3207 offset
= metaslab_block_alloc(msp
, asize
, txg
);
3208 metaslab_trace_add(zal
, mg
, msp
, asize
, d
, offset
, allocator
);
3210 if (offset
!= -1ULL) {
3211 /* Proactively passivate the metaslab, if needed */
3212 metaslab_segment_may_passivate(msp
);
3216 ASSERT(msp
->ms_loaded
);
3219 * We were unable to allocate from this metaslab so determine
3220 * a new weight for this metaslab. Now that we have loaded
3221 * the metaslab we can provide a better hint to the metaslab
3224 * For space-based metaslabs, we use the maximum block size.
3225 * This information is only available when the metaslab
3226 * is loaded and is more accurate than the generic free
3227 * space weight that was calculated by metaslab_weight().
3228 * This information allows us to quickly compare the maximum
3229 * available allocation in the metaslab to the allocation
3230 * size being requested.
3232 * For segment-based metaslabs, determine the new weight
3233 * based on the highest bucket in the range tree. We
3234 * explicitly use the loaded segment weight (i.e. the range
3235 * tree histogram) since it contains the space that is
3236 * currently available for allocation and is accurate
3237 * even within a sync pass.
3239 if (WEIGHT_IS_SPACEBASED(msp
->ms_weight
)) {
3240 uint64_t weight
= metaslab_block_maxsize(msp
);
3241 WEIGHT_SET_SPACEBASED(weight
);
3242 metaslab_passivate(msp
, weight
);
3244 metaslab_passivate(msp
,
3245 metaslab_weight_from_range_tree(msp
));
3249 * We have just failed an allocation attempt, check
3250 * that metaslab_should_allocate() agrees. Otherwise,
3251 * we may end up in an infinite loop retrying the same
3254 ASSERT(!metaslab_should_allocate(msp
, asize
));
3255 mutex_exit(&msp
->ms_lock
);
3257 mutex_exit(&msp
->ms_lock
);
3258 kmem_free(search
, sizeof (*search
));
3263 metaslab_group_alloc(metaslab_group_t
*mg
, zio_alloc_list_t
*zal
,
3264 uint64_t asize
, uint64_t txg
, uint64_t min_distance
, dva_t
*dva
, int d
,
3268 ASSERT(mg
->mg_initialized
);
3270 offset
= metaslab_group_alloc_normal(mg
, zal
, asize
, txg
,
3271 min_distance
, dva
, d
, allocator
);
3273 mutex_enter(&mg
->mg_lock
);
3274 if (offset
== -1ULL) {
3275 mg
->mg_failed_allocations
++;
3276 metaslab_trace_add(zal
, mg
, NULL
, asize
, d
,
3277 TRACE_GROUP_FAILURE
, allocator
);
3278 if (asize
== SPA_GANGBLOCKSIZE
) {
3280 * This metaslab group was unable to allocate
3281 * the minimum gang block size so it must be out of
3282 * space. We must notify the allocation throttle
3283 * to start skipping allocation attempts to this
3284 * metaslab group until more space becomes available.
3285 * Note: this failure cannot be caused by the
3286 * allocation throttle since the allocation throttle
3287 * is only responsible for skipping devices and
3288 * not failing block allocations.
3290 mg
->mg_no_free_space
= B_TRUE
;
3293 mg
->mg_allocations
++;
3294 mutex_exit(&mg
->mg_lock
);
3299 * If we have to write a ditto block (i.e. more than one DVA for a given BP)
3300 * on the same vdev as an existing DVA of this BP, then try to allocate it
3301 * at least (vdev_asize / (2 ^ ditto_same_vdev_distance_shift)) away from the
3304 int ditto_same_vdev_distance_shift
= 3;
3307 * Allocate a block for the specified i/o.
3310 metaslab_alloc_dva(spa_t
*spa
, metaslab_class_t
*mc
, uint64_t psize
,
3311 dva_t
*dva
, int d
, dva_t
*hintdva
, uint64_t txg
, int flags
,
3312 zio_alloc_list_t
*zal
, int allocator
)
3314 metaslab_group_t
*mg
, *rotor
;
3316 boolean_t try_hard
= B_FALSE
;
3318 ASSERT(!DVA_IS_VALID(&dva
[d
]));
3321 * For testing, make some blocks above a certain size be gang blocks.
3323 if (psize
>= metaslab_force_ganging
&& (ddi_get_lbolt() & 3) == 0) {
3324 metaslab_trace_add(zal
, NULL
, NULL
, psize
, d
, TRACE_FORCE_GANG
,
3326 return (SET_ERROR(ENOSPC
));
3330 * Start at the rotor and loop through all mgs until we find something.
3331 * Note that there's no locking on mc_rotor or mc_aliquot because
3332 * nothing actually breaks if we miss a few updates -- we just won't
3333 * allocate quite as evenly. It all balances out over time.
3335 * If we are doing ditto or log blocks, try to spread them across
3336 * consecutive vdevs. If we're forced to reuse a vdev before we've
3337 * allocated all of our ditto blocks, then try and spread them out on
3338 * that vdev as much as possible. If it turns out to not be possible,
3339 * gradually lower our standards until anything becomes acceptable.
3340 * Also, allocating on consecutive vdevs (as opposed to random vdevs)
3341 * gives us hope of containing our fault domains to something we're
3342 * able to reason about. Otherwise, any two top-level vdev failures
3343 * will guarantee the loss of data. With consecutive allocation,
3344 * only two adjacent top-level vdev failures will result in data loss.
3346 * If we are doing gang blocks (hintdva is non-NULL), try to keep
3347 * ourselves on the same vdev as our gang block header. That
3348 * way, we can hope for locality in vdev_cache, plus it makes our
3349 * fault domains something tractable.
3352 vd
= vdev_lookup_top(spa
, DVA_GET_VDEV(&hintdva
[d
]));
3355 * It's possible the vdev we're using as the hint no
3356 * longer exists or its mg has been closed (e.g. by
3357 * device removal). Consult the rotor when
3360 if (vd
!= NULL
&& vd
->vdev_mg
!= NULL
) {
3363 if (flags
& METASLAB_HINTBP_AVOID
&&
3364 mg
->mg_next
!= NULL
)
3369 } else if (d
!= 0) {
3370 vd
= vdev_lookup_top(spa
, DVA_GET_VDEV(&dva
[d
- 1]));
3371 mg
= vd
->vdev_mg
->mg_next
;
3377 * If the hint put us into the wrong metaslab class, or into a
3378 * metaslab group that has been passivated, just follow the rotor.
3380 if (mg
->mg_class
!= mc
|| mg
->mg_activation_count
<= 0)
3386 boolean_t allocatable
;
3388 ASSERT(mg
->mg_activation_count
== 1);
3392 * Don't allocate from faulted devices.
3395 spa_config_enter(spa
, SCL_ZIO
, FTAG
, RW_READER
);
3396 allocatable
= vdev_allocatable(vd
);
3397 spa_config_exit(spa
, SCL_ZIO
, FTAG
);
3399 allocatable
= vdev_allocatable(vd
);
3403 * Determine if the selected metaslab group is eligible
3404 * for allocations. If we're ganging then don't allow
3405 * this metaslab group to skip allocations since that would
3406 * inadvertently return ENOSPC and suspend the pool
3407 * even though space is still available.
3409 if (allocatable
&& !GANG_ALLOCATION(flags
) && !try_hard
) {
3410 allocatable
= metaslab_group_allocatable(mg
, rotor
,
3415 metaslab_trace_add(zal
, mg
, NULL
, psize
, d
,
3416 TRACE_NOT_ALLOCATABLE
, allocator
);
3420 ASSERT(mg
->mg_initialized
);
3423 * Avoid writing single-copy data to a failing,
3424 * non-redundant vdev, unless we've already tried all
3427 if ((vd
->vdev_stat
.vs_write_errors
> 0 ||
3428 vd
->vdev_state
< VDEV_STATE_HEALTHY
) &&
3429 d
== 0 && !try_hard
&& vd
->vdev_children
== 0) {
3430 metaslab_trace_add(zal
, mg
, NULL
, psize
, d
,
3431 TRACE_VDEV_ERROR
, allocator
);
3435 ASSERT(mg
->mg_class
== mc
);
3438 * If we don't need to try hard, then require that the
3439 * block be 1/8th of the device away from any other DVAs
3440 * in this BP. If we are trying hard, allow any offset
3441 * to be used (distance=0).
3443 uint64_t distance
= 0;
3445 distance
= vd
->vdev_asize
>>
3446 ditto_same_vdev_distance_shift
;
3447 if (distance
<= (1ULL << vd
->vdev_ms_shift
))
3451 uint64_t asize
= vdev_psize_to_asize(vd
, psize
);
3452 ASSERT(P2PHASE(asize
, 1ULL << vd
->vdev_ashift
) == 0);
3454 uint64_t offset
= metaslab_group_alloc(mg
, zal
, asize
, txg
,
3455 distance
, dva
, d
, allocator
);
3457 if (offset
!= -1ULL) {
3459 * If we've just selected this metaslab group,
3460 * figure out whether the corresponding vdev is
3461 * over- or under-used relative to the pool,
3462 * and set an allocation bias to even it out.
3464 if (mc
->mc_aliquot
== 0 && metaslab_bias_enabled
) {
3465 vdev_stat_t
*vs
= &vd
->vdev_stat
;
3468 vu
= (vs
->vs_alloc
* 100) / (vs
->vs_space
+ 1);
3469 cu
= (mc
->mc_alloc
* 100) / (mc
->mc_space
+ 1);
3472 * Calculate how much more or less we should
3473 * try to allocate from this device during
3474 * this iteration around the rotor.
3475 * For example, if a device is 80% full
3476 * and the pool is 20% full then we should
3477 * reduce allocations by 60% on this device.
3479 * mg_bias = (20 - 80) * 512K / 100 = -307K
3481 * This reduces allocations by 307K for this
3484 mg
->mg_bias
= ((cu
- vu
) *
3485 (int64_t)mg
->mg_aliquot
) / 100;
3486 } else if (!metaslab_bias_enabled
) {
3490 if (atomic_add_64_nv(&mc
->mc_aliquot
, asize
) >=
3491 mg
->mg_aliquot
+ mg
->mg_bias
) {
3492 mc
->mc_rotor
= mg
->mg_next
;
3496 DVA_SET_VDEV(&dva
[d
], vd
->vdev_id
);
3497 DVA_SET_OFFSET(&dva
[d
], offset
);
3498 DVA_SET_GANG(&dva
[d
], !!(flags
& METASLAB_GANG_HEADER
));
3499 DVA_SET_ASIZE(&dva
[d
], asize
);
3504 mc
->mc_rotor
= mg
->mg_next
;
3506 } while ((mg
= mg
->mg_next
) != rotor
);
3509 * If we haven't tried hard, do so now.
3516 bzero(&dva
[d
], sizeof (dva_t
));
3518 metaslab_trace_add(zal
, rotor
, NULL
, psize
, d
, TRACE_ENOSPC
, allocator
);
3519 return (SET_ERROR(ENOSPC
));
3523 metaslab_free_concrete(vdev_t
*vd
, uint64_t offset
, uint64_t asize
,
3524 boolean_t checkpoint
)
3527 spa_t
*spa
= vd
->vdev_spa
;
3529 ASSERT(vdev_is_concrete(vd
));
3530 ASSERT3U(spa_config_held(spa
, SCL_ALL
, RW_READER
), !=, 0);
3531 ASSERT3U(offset
>> vd
->vdev_ms_shift
, <, vd
->vdev_ms_count
);
3533 msp
= vd
->vdev_ms
[offset
>> vd
->vdev_ms_shift
];
3535 VERIFY(!msp
->ms_condensing
);
3536 VERIFY3U(offset
, >=, msp
->ms_start
);
3537 VERIFY3U(offset
+ asize
, <=, msp
->ms_start
+ msp
->ms_size
);
3538 VERIFY0(P2PHASE(offset
, 1ULL << vd
->vdev_ashift
));
3539 VERIFY0(P2PHASE(asize
, 1ULL << vd
->vdev_ashift
));
3541 metaslab_check_free_impl(vd
, offset
, asize
);
3543 mutex_enter(&msp
->ms_lock
);
3544 if (range_tree_is_empty(msp
->ms_freeing
) &&
3545 range_tree_is_empty(msp
->ms_checkpointing
)) {
3546 vdev_dirty(vd
, VDD_METASLAB
, msp
, spa_syncing_txg(spa
));
3550 ASSERT(spa_has_checkpoint(spa
));
3551 range_tree_add(msp
->ms_checkpointing
, offset
, asize
);
3553 range_tree_add(msp
->ms_freeing
, offset
, asize
);
3555 mutex_exit(&msp
->ms_lock
);
3560 metaslab_free_impl_cb(uint64_t inner_offset
, vdev_t
*vd
, uint64_t offset
,
3561 uint64_t size
, void *arg
)
3563 boolean_t
*checkpoint
= arg
;
3565 ASSERT3P(checkpoint
, !=, NULL
);
3567 if (vd
->vdev_ops
->vdev_op_remap
!= NULL
)
3568 vdev_indirect_mark_obsolete(vd
, offset
, size
);
3570 metaslab_free_impl(vd
, offset
, size
, *checkpoint
);
3574 metaslab_free_impl(vdev_t
*vd
, uint64_t offset
, uint64_t size
,
3575 boolean_t checkpoint
)
3577 spa_t
*spa
= vd
->vdev_spa
;
3579 ASSERT3U(spa_config_held(spa
, SCL_ALL
, RW_READER
), !=, 0);
3581 if (spa_syncing_txg(spa
) > spa_freeze_txg(spa
))
3584 if (spa
->spa_vdev_removal
!= NULL
&&
3585 spa
->spa_vdev_removal
->svr_vdev
== vd
&&
3586 vdev_is_concrete(vd
)) {
3588 * Note: we check if the vdev is concrete because when
3589 * we complete the removal, we first change the vdev to be
3590 * an indirect vdev (in open context), and then (in syncing
3591 * context) clear spa_vdev_removal.
3593 free_from_removing_vdev(vd
, offset
, size
);
3594 } else if (vd
->vdev_ops
->vdev_op_remap
!= NULL
) {
3595 vdev_indirect_mark_obsolete(vd
, offset
, size
);
3596 vd
->vdev_ops
->vdev_op_remap(vd
, offset
, size
,
3597 metaslab_free_impl_cb
, &checkpoint
);
3599 metaslab_free_concrete(vd
, offset
, size
, checkpoint
);
3603 typedef struct remap_blkptr_cb_arg
{
3605 spa_remap_cb_t rbca_cb
;
3606 vdev_t
*rbca_remap_vd
;
3607 uint64_t rbca_remap_offset
;
3609 } remap_blkptr_cb_arg_t
;
3612 remap_blkptr_cb(uint64_t inner_offset
, vdev_t
*vd
, uint64_t offset
,
3613 uint64_t size
, void *arg
)
3615 remap_blkptr_cb_arg_t
*rbca
= arg
;
3616 blkptr_t
*bp
= rbca
->rbca_bp
;
3618 /* We can not remap split blocks. */
3619 if (size
!= DVA_GET_ASIZE(&bp
->blk_dva
[0]))
3621 ASSERT0(inner_offset
);
3623 if (rbca
->rbca_cb
!= NULL
) {
3625 * At this point we know that we are not handling split
3626 * blocks and we invoke the callback on the previous
3627 * vdev which must be indirect.
3629 ASSERT3P(rbca
->rbca_remap_vd
->vdev_ops
, ==, &vdev_indirect_ops
);
3631 rbca
->rbca_cb(rbca
->rbca_remap_vd
->vdev_id
,
3632 rbca
->rbca_remap_offset
, size
, rbca
->rbca_cb_arg
);
3634 /* set up remap_blkptr_cb_arg for the next call */
3635 rbca
->rbca_remap_vd
= vd
;
3636 rbca
->rbca_remap_offset
= offset
;
3640 * The phys birth time is that of dva[0]. This ensures that we know
3641 * when each dva was written, so that resilver can determine which
3642 * blocks need to be scrubbed (i.e. those written during the time
3643 * the vdev was offline). It also ensures that the key used in
3644 * the ARC hash table is unique (i.e. dva[0] + phys_birth). If
3645 * we didn't change the phys_birth, a lookup in the ARC for a
3646 * remapped BP could find the data that was previously stored at
3647 * this vdev + offset.
3649 vdev_t
*oldvd
= vdev_lookup_top(vd
->vdev_spa
,
3650 DVA_GET_VDEV(&bp
->blk_dva
[0]));
3651 vdev_indirect_births_t
*vib
= oldvd
->vdev_indirect_births
;
3652 bp
->blk_phys_birth
= vdev_indirect_births_physbirth(vib
,
3653 DVA_GET_OFFSET(&bp
->blk_dva
[0]), DVA_GET_ASIZE(&bp
->blk_dva
[0]));
3655 DVA_SET_VDEV(&bp
->blk_dva
[0], vd
->vdev_id
);
3656 DVA_SET_OFFSET(&bp
->blk_dva
[0], offset
);
3660 * If the block pointer contains any indirect DVAs, modify them to refer to
3661 * concrete DVAs. Note that this will sometimes not be possible, leaving
3662 * the indirect DVA in place. This happens if the indirect DVA spans multiple
3663 * segments in the mapping (i.e. it is a "split block").
3665 * If the BP was remapped, calls the callback on the original dva (note the
3666 * callback can be called multiple times if the original indirect DVA refers
3667 * to another indirect DVA, etc).
3669 * Returns TRUE if the BP was remapped.
3672 spa_remap_blkptr(spa_t
*spa
, blkptr_t
*bp
, spa_remap_cb_t callback
, void *arg
)
3674 remap_blkptr_cb_arg_t rbca
;
3676 if (!zfs_remap_blkptr_enable
)
3679 if (!spa_feature_is_enabled(spa
, SPA_FEATURE_OBSOLETE_COUNTS
))
3683 * Dedup BP's can not be remapped, because ddt_phys_select() depends
3684 * on DVA[0] being the same in the BP as in the DDT (dedup table).
3686 if (BP_GET_DEDUP(bp
))
3690 * Gang blocks can not be remapped, because
3691 * zio_checksum_gang_verifier() depends on the DVA[0] that's in
3692 * the BP used to read the gang block header (GBH) being the same
3693 * as the DVA[0] that we allocated for the GBH.
3699 * Embedded BP's have no DVA to remap.
3701 if (BP_GET_NDVAS(bp
) < 1)
3705 * Note: we only remap dva[0]. If we remapped other dvas, we
3706 * would no longer know what their phys birth txg is.
3708 dva_t
*dva
= &bp
->blk_dva
[0];
3710 uint64_t offset
= DVA_GET_OFFSET(dva
);
3711 uint64_t size
= DVA_GET_ASIZE(dva
);
3712 vdev_t
*vd
= vdev_lookup_top(spa
, DVA_GET_VDEV(dva
));
3714 if (vd
->vdev_ops
->vdev_op_remap
== NULL
)
3718 rbca
.rbca_cb
= callback
;
3719 rbca
.rbca_remap_vd
= vd
;
3720 rbca
.rbca_remap_offset
= offset
;
3721 rbca
.rbca_cb_arg
= arg
;
3724 * remap_blkptr_cb() will be called in order for each level of
3725 * indirection, until a concrete vdev is reached or a split block is
3726 * encountered. old_vd and old_offset are updated within the callback
3727 * as we go from the one indirect vdev to the next one (either concrete
3728 * or indirect again) in that order.
3730 vd
->vdev_ops
->vdev_op_remap(vd
, offset
, size
, remap_blkptr_cb
, &rbca
);
3732 /* Check if the DVA wasn't remapped because it is a split block */
3733 if (DVA_GET_VDEV(&rbca
.rbca_bp
->blk_dva
[0]) == vd
->vdev_id
)
3740 * Undo the allocation of a DVA which happened in the given transaction group.
3743 metaslab_unalloc_dva(spa_t
*spa
, const dva_t
*dva
, uint64_t txg
)
3747 uint64_t vdev
= DVA_GET_VDEV(dva
);
3748 uint64_t offset
= DVA_GET_OFFSET(dva
);
3749 uint64_t size
= DVA_GET_ASIZE(dva
);
3751 ASSERT(DVA_IS_VALID(dva
));
3752 ASSERT3U(spa_config_held(spa
, SCL_ALL
, RW_READER
), !=, 0);
3754 if (txg
> spa_freeze_txg(spa
))
3757 if ((vd
= vdev_lookup_top(spa
, vdev
)) == NULL
||
3758 (offset
>> vd
->vdev_ms_shift
) >= vd
->vdev_ms_count
) {
3759 cmn_err(CE_WARN
, "metaslab_free_dva(): bad DVA %llu:%llu",
3760 (u_longlong_t
)vdev
, (u_longlong_t
)offset
);
3765 ASSERT(!vd
->vdev_removing
);
3766 ASSERT(vdev_is_concrete(vd
));
3767 ASSERT0(vd
->vdev_indirect_config
.vic_mapping_object
);
3768 ASSERT3P(vd
->vdev_indirect_mapping
, ==, NULL
);
3770 if (DVA_GET_GANG(dva
))
3771 size
= vdev_psize_to_asize(vd
, SPA_GANGBLOCKSIZE
);
3773 msp
= vd
->vdev_ms
[offset
>> vd
->vdev_ms_shift
];
3775 mutex_enter(&msp
->ms_lock
);
3776 range_tree_remove(msp
->ms_allocating
[txg
& TXG_MASK
],
3779 VERIFY(!msp
->ms_condensing
);
3780 VERIFY3U(offset
, >=, msp
->ms_start
);
3781 VERIFY3U(offset
+ size
, <=, msp
->ms_start
+ msp
->ms_size
);
3782 VERIFY3U(range_tree_space(msp
->ms_allocatable
) + size
, <=,
3784 VERIFY0(P2PHASE(offset
, 1ULL << vd
->vdev_ashift
));
3785 VERIFY0(P2PHASE(size
, 1ULL << vd
->vdev_ashift
));
3786 range_tree_add(msp
->ms_allocatable
, offset
, size
);
3787 mutex_exit(&msp
->ms_lock
);
3791 * Free the block represented by the given DVA.
3794 metaslab_free_dva(spa_t
*spa
, const dva_t
*dva
, boolean_t checkpoint
)
3796 uint64_t vdev
= DVA_GET_VDEV(dva
);
3797 uint64_t offset
= DVA_GET_OFFSET(dva
);
3798 uint64_t size
= DVA_GET_ASIZE(dva
);
3799 vdev_t
*vd
= vdev_lookup_top(spa
, vdev
);
3801 ASSERT(DVA_IS_VALID(dva
));
3802 ASSERT3U(spa_config_held(spa
, SCL_ALL
, RW_READER
), !=, 0);
3804 if (DVA_GET_GANG(dva
)) {
3805 size
= vdev_psize_to_asize(vd
, SPA_GANGBLOCKSIZE
);
3808 metaslab_free_impl(vd
, offset
, size
, checkpoint
);
3812 * Reserve some allocation slots. The reservation system must be called
3813 * before we call into the allocator. If there aren't any available slots
3814 * then the I/O will be throttled until an I/O completes and its slots are
3815 * freed up. The function returns true if it was successful in placing
3819 metaslab_class_throttle_reserve(metaslab_class_t
*mc
, int slots
, int allocator
,
3820 zio_t
*zio
, int flags
)
3822 uint64_t available_slots
= 0;
3823 boolean_t slot_reserved
= B_FALSE
;
3824 uint64_t max
= mc
->mc_alloc_max_slots
[allocator
];
3826 ASSERT(mc
->mc_alloc_throttle_enabled
);
3827 mutex_enter(&mc
->mc_lock
);
3829 uint64_t reserved_slots
=
3830 refcount_count(&mc
->mc_alloc_slots
[allocator
]);
3831 if (reserved_slots
< max
)
3832 available_slots
= max
- reserved_slots
;
3834 if (slots
<= available_slots
|| GANG_ALLOCATION(flags
)) {
3836 * We reserve the slots individually so that we can unreserve
3837 * them individually when an I/O completes.
3839 for (int d
= 0; d
< slots
; d
++) {
3841 refcount_add(&mc
->mc_alloc_slots
[allocator
],
3844 zio
->io_flags
|= ZIO_FLAG_IO_ALLOCATING
;
3845 slot_reserved
= B_TRUE
;
3848 mutex_exit(&mc
->mc_lock
);
3849 return (slot_reserved
);
3853 metaslab_class_throttle_unreserve(metaslab_class_t
*mc
, int slots
,
3854 int allocator
, zio_t
*zio
)
3856 ASSERT(mc
->mc_alloc_throttle_enabled
);
3857 mutex_enter(&mc
->mc_lock
);
3858 for (int d
= 0; d
< slots
; d
++) {
3859 (void) refcount_remove(&mc
->mc_alloc_slots
[allocator
],
3862 mutex_exit(&mc
->mc_lock
);
3866 metaslab_claim_concrete(vdev_t
*vd
, uint64_t offset
, uint64_t size
,
3870 spa_t
*spa
= vd
->vdev_spa
;
3873 if (offset
>> vd
->vdev_ms_shift
>= vd
->vdev_ms_count
)
3876 ASSERT3P(vd
->vdev_ms
, !=, NULL
);
3877 msp
= vd
->vdev_ms
[offset
>> vd
->vdev_ms_shift
];
3879 mutex_enter(&msp
->ms_lock
);
3881 if ((txg
!= 0 && spa_writeable(spa
)) || !msp
->ms_loaded
)
3882 error
= metaslab_activate(msp
, 0, METASLAB_WEIGHT_CLAIM
);
3884 * No need to fail in that case; someone else has activated the
3885 * metaslab, but that doesn't preclude us from using it.
3891 !range_tree_contains(msp
->ms_allocatable
, offset
, size
))
3892 error
= SET_ERROR(ENOENT
);
3894 if (error
|| txg
== 0) { /* txg == 0 indicates dry run */
3895 mutex_exit(&msp
->ms_lock
);
3899 VERIFY(!msp
->ms_condensing
);
3900 VERIFY0(P2PHASE(offset
, 1ULL << vd
->vdev_ashift
));
3901 VERIFY0(P2PHASE(size
, 1ULL << vd
->vdev_ashift
));
3902 VERIFY3U(range_tree_space(msp
->ms_allocatable
) - size
, <=,
3904 range_tree_remove(msp
->ms_allocatable
, offset
, size
);
3906 if (spa_writeable(spa
)) { /* don't dirty if we're zdb(8) */
3907 if (range_tree_is_empty(msp
->ms_allocating
[txg
& TXG_MASK
]))
3908 vdev_dirty(vd
, VDD_METASLAB
, msp
, txg
);
3909 range_tree_add(msp
->ms_allocating
[txg
& TXG_MASK
],
3913 mutex_exit(&msp
->ms_lock
);
3918 typedef struct metaslab_claim_cb_arg_t
{
3921 } metaslab_claim_cb_arg_t
;
3925 metaslab_claim_impl_cb(uint64_t inner_offset
, vdev_t
*vd
, uint64_t offset
,
3926 uint64_t size
, void *arg
)
3928 metaslab_claim_cb_arg_t
*mcca_arg
= arg
;
3930 if (mcca_arg
->mcca_error
== 0) {
3931 mcca_arg
->mcca_error
= metaslab_claim_concrete(vd
, offset
,
3932 size
, mcca_arg
->mcca_txg
);
3937 metaslab_claim_impl(vdev_t
*vd
, uint64_t offset
, uint64_t size
, uint64_t txg
)
3939 if (vd
->vdev_ops
->vdev_op_remap
!= NULL
) {
3940 metaslab_claim_cb_arg_t arg
;
3943 * Only zdb(8) can claim on indirect vdevs. This is used
3944 * to detect leaks of mapped space (that are not accounted
3945 * for in the obsolete counts, spacemap, or bpobj).
3947 ASSERT(!spa_writeable(vd
->vdev_spa
));
3951 vd
->vdev_ops
->vdev_op_remap(vd
, offset
, size
,
3952 metaslab_claim_impl_cb
, &arg
);
3954 if (arg
.mcca_error
== 0) {
3955 arg
.mcca_error
= metaslab_claim_concrete(vd
,
3958 return (arg
.mcca_error
);
3960 return (metaslab_claim_concrete(vd
, offset
, size
, txg
));
3965 * Intent log support: upon opening the pool after a crash, notify the SPA
3966 * of blocks that the intent log has allocated for immediate write, but
3967 * which are still considered free by the SPA because the last transaction
3968 * group didn't commit yet.
3971 metaslab_claim_dva(spa_t
*spa
, const dva_t
*dva
, uint64_t txg
)
3973 uint64_t vdev
= DVA_GET_VDEV(dva
);
3974 uint64_t offset
= DVA_GET_OFFSET(dva
);
3975 uint64_t size
= DVA_GET_ASIZE(dva
);
3978 if ((vd
= vdev_lookup_top(spa
, vdev
)) == NULL
) {
3979 return (SET_ERROR(ENXIO
));
3982 ASSERT(DVA_IS_VALID(dva
));
3984 if (DVA_GET_GANG(dva
))
3985 size
= vdev_psize_to_asize(vd
, SPA_GANGBLOCKSIZE
);
3987 return (metaslab_claim_impl(vd
, offset
, size
, txg
));
3991 metaslab_alloc(spa_t
*spa
, metaslab_class_t
*mc
, uint64_t psize
, blkptr_t
*bp
,
3992 int ndvas
, uint64_t txg
, blkptr_t
*hintbp
, int flags
,
3993 zio_alloc_list_t
*zal
, zio_t
*zio
, int allocator
)
3995 dva_t
*dva
= bp
->blk_dva
;
3996 dva_t
*hintdva
= hintbp
->blk_dva
;
3999 ASSERT(bp
->blk_birth
== 0);
4000 ASSERT(BP_PHYSICAL_BIRTH(bp
) == 0);
4002 spa_config_enter(spa
, SCL_ALLOC
, FTAG
, RW_READER
);
4004 if (mc
->mc_rotor
== NULL
) { /* no vdevs in this class */
4005 spa_config_exit(spa
, SCL_ALLOC
, FTAG
);
4006 return (SET_ERROR(ENOSPC
));
4009 ASSERT(ndvas
> 0 && ndvas
<= spa_max_replication(spa
));
4010 ASSERT(BP_GET_NDVAS(bp
) == 0);
4011 ASSERT(hintbp
== NULL
|| ndvas
<= BP_GET_NDVAS(hintbp
));
4012 ASSERT3P(zal
, !=, NULL
);
4014 for (int d
= 0; d
< ndvas
; d
++) {
4015 error
= metaslab_alloc_dva(spa
, mc
, psize
, dva
, d
, hintdva
,
4016 txg
, flags
, zal
, allocator
);
4018 for (d
--; d
>= 0; d
--) {
4019 metaslab_unalloc_dva(spa
, &dva
[d
], txg
);
4020 metaslab_group_alloc_decrement(spa
,
4021 DVA_GET_VDEV(&dva
[d
]), zio
, flags
,
4022 allocator
, B_FALSE
);
4023 bzero(&dva
[d
], sizeof (dva_t
));
4025 spa_config_exit(spa
, SCL_ALLOC
, FTAG
);
4029 * Update the metaslab group's queue depth
4030 * based on the newly allocated dva.
4032 metaslab_group_alloc_increment(spa
,
4033 DVA_GET_VDEV(&dva
[d
]), zio
, flags
, allocator
);
4038 ASSERT(BP_GET_NDVAS(bp
) == ndvas
);
4040 spa_config_exit(spa
, SCL_ALLOC
, FTAG
);
4042 BP_SET_BIRTH(bp
, txg
, txg
);
4048 metaslab_free(spa_t
*spa
, const blkptr_t
*bp
, uint64_t txg
, boolean_t now
)
4050 const dva_t
*dva
= bp
->blk_dva
;
4051 int ndvas
= BP_GET_NDVAS(bp
);
4053 ASSERT(!BP_IS_HOLE(bp
));
4054 ASSERT(!now
|| bp
->blk_birth
>= spa_syncing_txg(spa
));
4057 * If we have a checkpoint for the pool we need to make sure that
4058 * the blocks that we free that are part of the checkpoint won't be
4059 * reused until the checkpoint is discarded or we revert to it.
4061 * The checkpoint flag is passed down the metaslab_free code path
4062 * and is set whenever we want to add a block to the checkpoint's
4063 * accounting. That is, we "checkpoint" blocks that existed at the
4064 * time the checkpoint was created and are therefore referenced by
4065 * the checkpointed uberblock.
4067 * Note that, we don't checkpoint any blocks if the current
4068 * syncing txg <= spa_checkpoint_txg. We want these frees to sync
4069 * normally as they will be referenced by the checkpointed uberblock.
4071 boolean_t checkpoint
= B_FALSE
;
4072 if (bp
->blk_birth
<= spa
->spa_checkpoint_txg
&&
4073 spa_syncing_txg(spa
) > spa
->spa_checkpoint_txg
) {
4075 * At this point, if the block is part of the checkpoint
4076 * there is no way it was created in the current txg.
4079 ASSERT3U(spa_syncing_txg(spa
), ==, txg
);
4080 checkpoint
= B_TRUE
;
4083 spa_config_enter(spa
, SCL_FREE
, FTAG
, RW_READER
);
4085 for (int d
= 0; d
< ndvas
; d
++) {
4087 metaslab_unalloc_dva(spa
, &dva
[d
], txg
);
4089 ASSERT3U(txg
, ==, spa_syncing_txg(spa
));
4090 metaslab_free_dva(spa
, &dva
[d
], checkpoint
);
4094 spa_config_exit(spa
, SCL_FREE
, FTAG
);
4098 metaslab_claim(spa_t
*spa
, const blkptr_t
*bp
, uint64_t txg
)
4100 const dva_t
*dva
= bp
->blk_dva
;
4101 int ndvas
= BP_GET_NDVAS(bp
);
4104 ASSERT(!BP_IS_HOLE(bp
));
4108 * First do a dry run to make sure all DVAs are claimable,
4109 * so we don't have to unwind from partial failures below.
4111 if ((error
= metaslab_claim(spa
, bp
, 0)) != 0)
4115 spa_config_enter(spa
, SCL_ALLOC
, FTAG
, RW_READER
);
4117 for (int d
= 0; d
< ndvas
; d
++)
4118 if ((error
= metaslab_claim_dva(spa
, &dva
[d
], txg
)) != 0)
4121 spa_config_exit(spa
, SCL_ALLOC
, FTAG
);
4123 ASSERT(error
== 0 || txg
== 0);
4130 metaslab_check_free_impl_cb(uint64_t inner
, vdev_t
*vd
, uint64_t offset
,
4131 uint64_t size
, void *arg
)
4133 if (vd
->vdev_ops
== &vdev_indirect_ops
)
4136 metaslab_check_free_impl(vd
, offset
, size
);
4140 metaslab_check_free_impl(vdev_t
*vd
, uint64_t offset
, uint64_t size
)
4143 spa_t
*spa
= vd
->vdev_spa
;
4145 if ((zfs_flags
& ZFS_DEBUG_ZIO_FREE
) == 0)
4148 if (vd
->vdev_ops
->vdev_op_remap
!= NULL
) {
4149 vd
->vdev_ops
->vdev_op_remap(vd
, offset
, size
,
4150 metaslab_check_free_impl_cb
, NULL
);
4154 ASSERT(vdev_is_concrete(vd
));
4155 ASSERT3U(offset
>> vd
->vdev_ms_shift
, <, vd
->vdev_ms_count
);
4156 ASSERT3U(spa_config_held(spa
, SCL_ALL
, RW_READER
), !=, 0);
4158 msp
= vd
->vdev_ms
[offset
>> vd
->vdev_ms_shift
];
4160 mutex_enter(&msp
->ms_lock
);
4162 range_tree_verify(msp
->ms_allocatable
, offset
, size
);
4164 range_tree_verify(msp
->ms_freeing
, offset
, size
);
4165 range_tree_verify(msp
->ms_checkpointing
, offset
, size
);
4166 range_tree_verify(msp
->ms_freed
, offset
, size
);
4167 for (int j
= 0; j
< TXG_DEFER_SIZE
; j
++)
4168 range_tree_verify(msp
->ms_defer
[j
], offset
, size
);
4169 mutex_exit(&msp
->ms_lock
);
4173 metaslab_check_free(spa_t
*spa
, const blkptr_t
*bp
)
4175 if ((zfs_flags
& ZFS_DEBUG_ZIO_FREE
) == 0)
4178 spa_config_enter(spa
, SCL_VDEV
, FTAG
, RW_READER
);
4179 for (int i
= 0; i
< BP_GET_NDVAS(bp
); i
++) {
4180 uint64_t vdev
= DVA_GET_VDEV(&bp
->blk_dva
[i
]);
4181 vdev_t
*vd
= vdev_lookup_top(spa
, vdev
);
4182 uint64_t offset
= DVA_GET_OFFSET(&bp
->blk_dva
[i
]);
4183 uint64_t size
= DVA_GET_ASIZE(&bp
->blk_dva
[i
]);
4185 if (DVA_GET_GANG(&bp
->blk_dva
[i
]))
4186 size
= vdev_psize_to_asize(vd
, SPA_GANGBLOCKSIZE
);
4188 ASSERT3P(vd
, !=, NULL
);
4190 metaslab_check_free_impl(vd
, offset
, size
);
4192 spa_config_exit(spa
, SCL_VDEV
, FTAG
);