util/throttle.c

   1 /*
   2  * QEMU throttling infrastructure
   3  *
   4  * Copyright (C) Nodalink, EURL. 2013-2014
   5  * Copyright (C) Igalia, S.L. 2015
   6  *
   7  * Authors:
   8  *   Benoît Canet <benoit.canet@nodalink.com>
   9  *   Alberto Garcia <berto@igalia.com>
  10  *
  11  * This program is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU General Public License as
  13  * published by the Free Software Foundation; either version 2 or
  14  * (at your option) version 3 of the License.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  23  */
  24
  25 #include "qemu/osdep.h"
  26 #include "qapi/error.h"
  27 #include "qemu/throttle.h"
  28 #include "qemu/timer.h"
  29 #include "block/aio.h"
  30
  31 /* This function make a bucket leak
  32  *
  33  * @bkt:   the bucket to make leak
  34  * @delta_ns: the time delta
  35  */
  36 void throttle_leak_bucket(LeakyBucket *bkt, int64_t delta_ns)
  37 {
  38     double leak;
  39
  40     /* compute how much to leak */
  41     leak = (bkt->avg * (double) delta_ns) / NANOSECONDS_PER_SECOND;
  42
  43     /* make the bucket leak */
  44     bkt->level = MAX(bkt->level - leak, 0);
  45
  46     /* if we allow bursts for more than one second we also need to
  47      * keep track of bkt->burst_level so the bkt->max goal per second
  48      * is attained */
  49     if (bkt->burst_length > 1) {
  50         leak = (bkt->max * (double) delta_ns) / NANOSECONDS_PER_SECOND;
  51         bkt->burst_level = MAX(bkt->burst_level - leak, 0);
  52     }
  53 }
  54
  55 /* Calculate the time delta since last leak and make proportionals leaks
  56  *
  57  * @now:      the current timestamp in ns
  58  */
  59 static void throttle_do_leak(ThrottleState *ts, int64_t now)
  60 {
  61     /* compute the time elapsed since the last leak */
  62     int64_t delta_ns = now - ts->previous_leak;
  63     int i;
  64
  65     ts->previous_leak = now;
  66
  67     if (delta_ns <= 0) {
  68         return;
  69     }
  70
  71     /* make each bucket leak */
  72     for (i = 0; i < BUCKETS_COUNT; i++) {
  73         throttle_leak_bucket(&ts->cfg.buckets[i], delta_ns);
  74     }
  75 }
  76
  77 /* do the real job of computing the time to wait
  78  *
  79  * @limit: the throttling limit
  80  * @extra: the number of operation to delay
  81  * @ret:   the time to wait in ns
  82  */
  83 static int64_t throttle_do_compute_wait(double limit, double extra)
  84 {
  85     double wait = extra * NANOSECONDS_PER_SECOND;
  86     wait /= limit;
  87     return wait;
  88 }
  89
  90 /* This function compute the wait time in ns that a leaky bucket should trigger
  91  *
  92  * @bkt: the leaky bucket we operate on
  93  * @ret: the resulting wait time in ns or 0 if the operation can go through
  94  */
  95 int64_t throttle_compute_wait(LeakyBucket *bkt)
  96 {
  97     double extra; /* the number of extra units blocking the io */
  98     double bucket_size;   /* I/O before throttling to bkt->avg */
  99     double burst_bucket_size; /* Before throttling to bkt->max */
 100
 101     if (!bkt->avg) {
 102         return 0;
 103     }
 104
 105     if (!bkt->max) {
 106         /* If bkt->max is 0 we still want to allow short bursts of I/O
 107          * from the guest, otherwise every other request will be throttled
 108          * and performance will suffer considerably. */
 109         bucket_size = (double) bkt->avg / 10;
 110         burst_bucket_size = 0;
 111     } else {
 112         /* If we have a burst limit then we have to wait until all I/O
 113          * at burst rate has finished before throttling to bkt->avg */
 114         bucket_size = bkt->max * bkt->burst_length;
 115         burst_bucket_size = (double) bkt->max / 10;
 116     }
 117
 118     /* If the main bucket is full then we have to wait */
 119     extra = bkt->level - bucket_size;
 120     if (extra > 0) {
 121         return throttle_do_compute_wait(bkt->avg, extra);
 122     }
 123
 124     /* If the main bucket is not full yet we still have to check the
 125      * burst bucket in order to enforce the burst limit */
 126     if (bkt->burst_length > 1) {
 127         assert(bkt->max > 0); /* see throttle_is_valid() */
 128         extra = bkt->burst_level - burst_bucket_size;
 129         if (extra > 0) {
 130             return throttle_do_compute_wait(bkt->max, extra);
 131         }
 132     }
 133
 134     return 0;
 135 }
 136
 137 /* This function compute the time that must be waited while this IO
 138  *
 139  * @is_write:   true if the current IO is a write, false if it's a read
 140  * @ret:        time to wait
 141  */
 142 static int64_t throttle_compute_wait_for(ThrottleState *ts,
 143                                          bool is_write)
 144 {
 145     BucketType to_check[2][4] = { {THROTTLE_BPS_TOTAL,
 146                                    THROTTLE_OPS_TOTAL,
 147                                    THROTTLE_BPS_READ,
 148                                    THROTTLE_OPS_READ},
 149                                   {THROTTLE_BPS_TOTAL,
 150                                    THROTTLE_OPS_TOTAL,
 151                                    THROTTLE_BPS_WRITE,
 152                                    THROTTLE_OPS_WRITE}, };
 153     int64_t wait, max_wait = 0;
 154     int i;
 155
 156     for (i = 0; i < 4; i++) {
 157         BucketType index = to_check[is_write][i];
 158         wait = throttle_compute_wait(&ts->cfg.buckets[index]);
 159         if (wait > max_wait) {
 160             max_wait = wait;
 161         }
 162     }
 163
 164     return max_wait;
 165 }
 166
 167 /* compute the timer for this type of operation
 168  *
 169  * @is_write:   the type of operation
 170  * @now:        the current clock timestamp
 171  * @next_timestamp: the resulting timer
 172  * @ret:        true if a timer must be set
 173  */
 174 static bool throttle_compute_timer(ThrottleState *ts,
 175                                    bool is_write,
 176                                    int64_t now,
 177                                    int64_t *next_timestamp)
 178 {
 179     int64_t wait;
 180
 181     /* leak proportionally to the time elapsed */
 182     throttle_do_leak(ts, now);
 183
 184     /* compute the wait time if any */
 185     wait = throttle_compute_wait_for(ts, is_write);
 186
 187     /* if the code must wait compute when the next timer should fire */
 188     if (wait) {
 189         *next_timestamp = now + wait;
 190         return true;
 191     }
 192
 193     /* else no need to wait at all */
 194     *next_timestamp = now;
 195     return false;
 196 }
 197
 198 /* Add timers to event loop */
 199 void throttle_timers_attach_aio_context(ThrottleTimers *tt,
 200                                         AioContext *new_context)
 201 {
 202     tt->timers[0] = aio_timer_new(new_context, tt->clock_type, SCALE_NS,
 203                                   tt->read_timer_cb, tt->timer_opaque);
 204     tt->timers[1] = aio_timer_new(new_context, tt->clock_type, SCALE_NS,
 205                                   tt->write_timer_cb, tt->timer_opaque);
 206 }
 207
 208 /*
 209  * Initialize the ThrottleConfig structure to a valid state
 210  * @cfg: the config to initialize
 211  */
 212 void throttle_config_init(ThrottleConfig *cfg)
 213 {
 214     unsigned i;
 215     memset(cfg, 0, sizeof(*cfg));
 216     for (i = 0; i < BUCKETS_COUNT; i++) {
 217         cfg->buckets[i].burst_length = 1;
 218     }
 219 }
 220
 221 /* To be called first on the ThrottleState */
 222 void throttle_init(ThrottleState *ts)
 223 {
 224     memset(ts, 0, sizeof(ThrottleState));
 225     throttle_config_init(&ts->cfg);
 226 }
 227
 228 /* To be called first on the ThrottleTimers */
 229 void throttle_timers_init(ThrottleTimers *tt,
 230                           AioContext *aio_context,
 231                           QEMUClockType clock_type,
 232                           QEMUTimerCB *read_timer_cb,
 233                           QEMUTimerCB *write_timer_cb,
 234                           void *timer_opaque)
 235 {
 236     memset(tt, 0, sizeof(ThrottleTimers));
 237
 238     tt->clock_type = clock_type;
 239     tt->read_timer_cb = read_timer_cb;
 240     tt->write_timer_cb = write_timer_cb;
 241     tt->timer_opaque = timer_opaque;
 242     throttle_timers_attach_aio_context(tt, aio_context);
 243 }
 244
 245 /* destroy a timer */
 246 static void throttle_timer_destroy(QEMUTimer **timer)
 247 {
 248     assert(*timer != NULL);
 249
 250     timer_del(*timer);
 251     timer_free(*timer);
 252     *timer = NULL;
 253 }
 254
 255 /* Remove timers from event loop */
 256 void throttle_timers_detach_aio_context(ThrottleTimers *tt)
 257 {
 258     int i;
 259
 260     for (i = 0; i < 2; i++) {
 261         throttle_timer_destroy(&tt->timers[i]);
 262     }
 263 }
 264
 265 /* To be called last on the ThrottleTimers */
 266 void throttle_timers_destroy(ThrottleTimers *tt)
 267 {
 268     throttle_timers_detach_aio_context(tt);
 269 }
 270
 271 /* is any throttling timer configured */
 272 bool throttle_timers_are_initialized(ThrottleTimers *tt)
 273 {
 274     if (tt->timers[0]) {
 275         return true;
 276     }
 277
 278     return false;
 279 }
 280
 281 /* Does any throttling must be done
 282  *
 283  * @cfg: the throttling configuration to inspect
 284  * @ret: true if throttling must be done else false
 285  */
 286 bool throttle_enabled(ThrottleConfig *cfg)
 287 {
 288     int i;
 289
 290     for (i = 0; i < BUCKETS_COUNT; i++) {
 291         if (cfg->buckets[i].avg > 0) {
 292             return true;
 293         }
 294     }
 295
 296     return false;
 297 }
 298
 299 /* check if a throttling configuration is valid
 300  * @cfg: the throttling configuration to inspect
 301  * @ret: true if valid else false
 302  * @errp: error object
 303  */
 304 bool throttle_is_valid(ThrottleConfig *cfg, Error **errp)
 305 {
 306     int i;
 307     bool bps_flag, ops_flag;
 308     bool bps_max_flag, ops_max_flag;
 309
 310     bps_flag = cfg->buckets[THROTTLE_BPS_TOTAL].avg &&
 311                (cfg->buckets[THROTTLE_BPS_READ].avg ||
 312                 cfg->buckets[THROTTLE_BPS_WRITE].avg);
 313
 314     ops_flag = cfg->buckets[THROTTLE_OPS_TOTAL].avg &&
 315                (cfg->buckets[THROTTLE_OPS_READ].avg ||
 316                 cfg->buckets[THROTTLE_OPS_WRITE].avg);
 317
 318     bps_max_flag = cfg->buckets[THROTTLE_BPS_TOTAL].max &&
 319                   (cfg->buckets[THROTTLE_BPS_READ].max  ||
 320                    cfg->buckets[THROTTLE_BPS_WRITE].max);
 321
 322     ops_max_flag = cfg->buckets[THROTTLE_OPS_TOTAL].max &&
 323                    (cfg->buckets[THROTTLE_OPS_READ].max ||
 324                    cfg->buckets[THROTTLE_OPS_WRITE].max);
 325
 326     if (bps_flag || ops_flag || bps_max_flag || ops_max_flag) {
 327         error_setg(errp, "bps/iops/max total values and read/write values"
 328                    " cannot be used at the same time");
 329         return false;
 330     }
 331
 332     if (cfg->op_size &&
 333         !cfg->buckets[THROTTLE_OPS_TOTAL].avg &&
 334         !cfg->buckets[THROTTLE_OPS_READ].avg &&
 335         !cfg->buckets[THROTTLE_OPS_WRITE].avg) {
 336         error_setg(errp, "iops size requires an iops value to be set");
 337         return false;
 338     }
 339
 340     for (i = 0; i < BUCKETS_COUNT; i++) {
 341         LeakyBucket *bkt = &cfg->buckets[i];
 342         if (bkt->avg > THROTTLE_VALUE_MAX || bkt->max > THROTTLE_VALUE_MAX) {
 343             error_setg(errp, "bps/iops/max values must be within [0, %lld]",
 344                        THROTTLE_VALUE_MAX);
 345             return false;
 346         }
 347
 348         if (!bkt->burst_length) {
 349             error_setg(errp, "the burst length cannot be 0");
 350             return false;
 351         }
 352
 353         if (bkt->burst_length > 1 && !bkt->max) {
 354             error_setg(errp, "burst length set without burst rate");
 355             return false;
 356         }
 357
 358         if (bkt->max && bkt->burst_length > THROTTLE_VALUE_MAX / bkt->max) {
 359             error_setg(errp, "burst length too high for this burst rate");
 360             return false;
 361         }
 362
 363         if (bkt->max && !bkt->avg) {
 364             error_setg(errp, "bps_max/iops_max require corresponding"
 365                        " bps/iops values");
 366             return false;
 367         }
 368
 369         if (bkt->max && bkt->max < bkt->avg) {
 370             error_setg(errp, "bps_max/iops_max cannot be lower than bps/iops");
 371             return false;
 372         }
 373     }
 374
 375     return true;
 376 }
 377
 378 /* Used to configure the throttle
 379  *
 380  * @ts: the throttle state we are working on
 381  * @clock_type: the group's clock_type
 382  * @cfg: the config to set
 383  */
 384 void throttle_config(ThrottleState *ts,
 385                      QEMUClockType clock_type,
 386                      ThrottleConfig *cfg)
 387 {
 388     int i;
 389
 390     ts->cfg = *cfg;
 391
 392     /* Zero bucket level */
 393     for (i = 0; i < BUCKETS_COUNT; i++) {
 394         ts->cfg.buckets[i].level = 0;
 395         ts->cfg.buckets[i].burst_level = 0;
 396     }
 397
 398     ts->previous_leak = qemu_clock_get_ns(clock_type);
 399 }
 400
 401 /* used to get config
 402  *
 403  * @ts:  the throttle state we are working on
 404  * @cfg: the config to write
 405  */
 406 void throttle_get_config(ThrottleState *ts, ThrottleConfig *cfg)
 407 {
 408     *cfg = ts->cfg;
 409 }
 410
 411
 412 /* Schedule the read or write timer if needed
 413  *
 414  * NOTE: this function is not unit tested due to it's usage of timer_mod
 415  *
 416  * @tt:       the timers structure
 417  * @is_write: the type of operation (read/write)
 418  * @ret:      true if the timer has been scheduled else false
 419  */
 420 bool throttle_schedule_timer(ThrottleState *ts,
 421                              ThrottleTimers *tt,
 422                              bool is_write)
 423 {
 424     int64_t now = qemu_clock_get_ns(tt->clock_type);
 425     int64_t next_timestamp;
 426     bool must_wait;
 427
 428     must_wait = throttle_compute_timer(ts,
 429                                        is_write,
 430                                        now,
 431                                        &next_timestamp);
 432
 433     /* request not throttled */
 434     if (!must_wait) {
 435         return false;
 436     }
 437
 438     /* request throttled and timer pending -> do nothing */
 439     if (timer_pending(tt->timers[is_write])) {
 440         return true;
 441     }
 442
 443     /* request throttled and timer not pending -> arm timer */
 444     timer_mod(tt->timers[is_write], next_timestamp);
 445     return true;
 446 }
 447
 448 /* do the accounting for this operation
 449  *
 450  * @is_write: the type of operation (read/write)
 451  * @size:     the size of the operation
 452  */
 453 void throttle_account(ThrottleState *ts, bool is_write, uint64_t size)
 454 {
 455     const BucketType bucket_types_size[2][2] = {
 456         { THROTTLE_BPS_TOTAL, THROTTLE_BPS_READ },
 457         { THROTTLE_BPS_TOTAL, THROTTLE_BPS_WRITE }
 458     };
 459     const BucketType bucket_types_units[2][2] = {
 460         { THROTTLE_OPS_TOTAL, THROTTLE_OPS_READ },
 461         { THROTTLE_OPS_TOTAL, THROTTLE_OPS_WRITE }
 462     };
 463     double units = 1.0;
 464     unsigned i;
 465
 466     /* if cfg.op_size is defined and smaller than size we compute unit count */
 467     if (ts->cfg.op_size && size > ts->cfg.op_size) {
 468         units = (double) size / ts->cfg.op_size;
 469     }
 470
 471     for (i = 0; i < 2; i++) {
 472         LeakyBucket *bkt;
 473
 474         bkt = &ts->cfg.buckets[bucket_types_size[is_write][i]];
 475         bkt->level += size;
 476         if (bkt->burst_length > 1) {
 477             bkt->burst_level += size;
 478         }
 479
 480         bkt = &ts->cfg.buckets[bucket_types_units[is_write][i]];
 481         bkt->level += units;
 482         if (bkt->burst_length > 1) {
 483             bkt->burst_level += units;
 484         }
 485     }
 486 }
 487
 488 /* return a ThrottleConfig based on the options in a ThrottleLimits
 489  *
 490  * @arg:    the ThrottleLimits object to read from
 491  * @cfg:    the ThrottleConfig to edit
 492  * @errp:   error object
 493  */
 494 void throttle_limits_to_config(ThrottleLimits *arg, ThrottleConfig *cfg,
 495                                Error **errp)
 496 {
 497     if (arg->has_bps_total) {
 498         cfg->buckets[THROTTLE_BPS_TOTAL].avg = arg->bps_total;
 499     }
 500     if (arg->has_bps_read) {
 501         cfg->buckets[THROTTLE_BPS_READ].avg  = arg->bps_read;
 502     }
 503     if (arg->has_bps_write) {
 504         cfg->buckets[THROTTLE_BPS_WRITE].avg = arg->bps_write;
 505     }
 506
 507     if (arg->has_iops_total) {
 508         cfg->buckets[THROTTLE_OPS_TOTAL].avg = arg->iops_total;
 509     }
 510     if (arg->has_iops_read) {
 511         cfg->buckets[THROTTLE_OPS_READ].avg  = arg->iops_read;
 512     }
 513     if (arg->has_iops_write) {
 514         cfg->buckets[THROTTLE_OPS_WRITE].avg = arg->iops_write;
 515     }
 516
 517     if (arg->has_bps_total_max) {
 518         cfg->buckets[THROTTLE_BPS_TOTAL].max = arg->bps_total_max;
 519     }
 520     if (arg->has_bps_read_max) {
 521         cfg->buckets[THROTTLE_BPS_READ].max = arg->bps_read_max;
 522     }
 523     if (arg->has_bps_write_max) {
 524         cfg->buckets[THROTTLE_BPS_WRITE].max = arg->bps_write_max;
 525     }
 526     if (arg->has_iops_total_max) {
 527         cfg->buckets[THROTTLE_OPS_TOTAL].max = arg->iops_total_max;
 528     }
 529     if (arg->has_iops_read_max) {
 530         cfg->buckets[THROTTLE_OPS_READ].max = arg->iops_read_max;
 531     }
 532     if (arg->has_iops_write_max) {
 533         cfg->buckets[THROTTLE_OPS_WRITE].max = arg->iops_write_max;
 534     }
 535
 536     if (arg->has_bps_total_max_length) {
 537         if (arg->bps_total_max_length > UINT_MAX) {
 538             error_setg(errp, "bps-total-max-length value must be in"
 539                              " the range [0, %u]", UINT_MAX);
 540             return;
 541         }
 542         cfg->buckets[THROTTLE_BPS_TOTAL].burst_length = arg->bps_total_max_length;
 543     }
 544     if (arg->has_bps_read_max_length) {
 545         if (arg->bps_read_max_length > UINT_MAX) {
 546             error_setg(errp, "bps-read-max-length value must be in"
 547                              " the range [0, %u]", UINT_MAX);
 548             return;
 549         }
 550         cfg->buckets[THROTTLE_BPS_READ].burst_length = arg->bps_read_max_length;
 551     }
 552     if (arg->has_bps_write_max_length) {
 553         if (arg->bps_write_max_length > UINT_MAX) {
 554             error_setg(errp, "bps-write-max-length value must be in"
 555                              " the range [0, %u]", UINT_MAX);
 556             return;
 557         }
 558         cfg->buckets[THROTTLE_BPS_WRITE].burst_length = arg->bps_write_max_length;
 559     }
 560     if (arg->has_iops_total_max_length) {
 561         if (arg->iops_total_max_length > UINT_MAX) {
 562             error_setg(errp, "iops-total-max-length value must be in"
 563                              " the range [0, %u]", UINT_MAX);
 564             return;
 565         }
 566         cfg->buckets[THROTTLE_OPS_TOTAL].burst_length = arg->iops_total_max_length;
 567     }
 568     if (arg->has_iops_read_max_length) {
 569         if (arg->iops_read_max_length > UINT_MAX) {
 570             error_setg(errp, "iops-read-max-length value must be in"
 571                              " the range [0, %u]", UINT_MAX);
 572             return;
 573         }
 574         cfg->buckets[THROTTLE_OPS_READ].burst_length = arg->iops_read_max_length;
 575     }
 576     if (arg->has_iops_write_max_length) {
 577         if (arg->iops_write_max_length > UINT_MAX) {
 578             error_setg(errp, "iops-write-max-length value must be in"
 579                              " the range [0, %u]", UINT_MAX);
 580             return;
 581         }
 582         cfg->buckets[THROTTLE_OPS_WRITE].burst_length = arg->iops_write_max_length;
 583     }
 584
 585     if (arg->has_iops_size) {
 586         cfg->op_size = arg->iops_size;
 587     }
 588
 589     throttle_is_valid(cfg, errp);
 590 }
 591
 592 /* write the options of a ThrottleConfig to a ThrottleLimits
 593  *
 594  * @cfg:    the ThrottleConfig to read from
 595  * @var:    the ThrottleLimits to write to
 596  */
 597 void throttle_config_to_limits(ThrottleConfig *cfg, ThrottleLimits *var)
 598 {
 599     var->bps_total               = cfg->buckets[THROTTLE_BPS_TOTAL].avg;
 600     var->bps_read                = cfg->buckets[THROTTLE_BPS_READ].avg;
 601     var->bps_write               = cfg->buckets[THROTTLE_BPS_WRITE].avg;
 602     var->iops_total              = cfg->buckets[THROTTLE_OPS_TOTAL].avg;
 603     var->iops_read               = cfg->buckets[THROTTLE_OPS_READ].avg;
 604     var->iops_write              = cfg->buckets[THROTTLE_OPS_WRITE].avg;
 605     var->bps_total_max           = cfg->buckets[THROTTLE_BPS_TOTAL].max;
 606     var->bps_read_max            = cfg->buckets[THROTTLE_BPS_READ].max;
 607     var->bps_write_max           = cfg->buckets[THROTTLE_BPS_WRITE].max;
 608     var->iops_total_max          = cfg->buckets[THROTTLE_OPS_TOTAL].max;
 609     var->iops_read_max           = cfg->buckets[THROTTLE_OPS_READ].max;
 610     var->iops_write_max          = cfg->buckets[THROTTLE_OPS_WRITE].max;
 611     var->bps_total_max_length    = cfg->buckets[THROTTLE_BPS_TOTAL].burst_length;
 612     var->bps_read_max_length     = cfg->buckets[THROTTLE_BPS_READ].burst_length;
 613     var->bps_write_max_length    = cfg->buckets[THROTTLE_BPS_WRITE].burst_length;
 614     var->iops_total_max_length   = cfg->buckets[THROTTLE_OPS_TOTAL].burst_length;
 615     var->iops_read_max_length    = cfg->buckets[THROTTLE_OPS_READ].burst_length;
 616     var->iops_write_max_length   = cfg->buckets[THROTTLE_OPS_WRITE].burst_length;
 617     var->iops_size               = cfg->op_size;
 618
 619     var->has_bps_total = true;
 620     var->has_bps_read = true;
 621     var->has_bps_write = true;
 622     var->has_iops_total = true;
 623     var->has_iops_read = true;
 624     var->has_iops_write = true;
 625     var->has_bps_total_max = true;
 626     var->has_bps_read_max = true;
 627     var->has_bps_write_max = true;
 628     var->has_iops_total_max = true;
 629     var->has_iops_read_max = true;
 630     var->has_iops_write_max = true;
 631     var->has_bps_read_max_length = true;
 632     var->has_bps_total_max_length = true;
 633     var->has_bps_write_max_length = true;
 634     var->has_iops_total_max_length = true;
 635     var->has_iops_read_max_length = true;
 636     var->has_iops_write_max_length = true;
 637     var->has_iops_size = true;
 638 }