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6 <refentry id="ctdb-statistics.7">
9 <refentrytitle>ctdb-statistics</refentrytitle>
10 <manvolnum>7</manvolnum>
11 <refmiscinfo class="source">ctdb</refmiscinfo>
12 <refmiscinfo class="manual">CTDB - clustered TDB database</refmiscinfo>
16 <refname>ctdb-statistics</refname>
17 <refpurpose>CTDB statistics output</refpurpose>
21 <title>OVERALL STATISTICS</title>
24 CTDB maintains information about various messages communicated
25 and some of the important operations per node. See the
26 <citerefentry><refentrytitle>ctdb</refentrytitle>
27 <manvolnum>1</manvolnum></citerefentry> commands
28 <command>statistics</command> and <command>statisticsreset</command>
29 for displaying statistics.
33 <title>Example: ctdb statistics</title>
36 Current time of statistics : Fri Sep 12 13:32:32 2014
37 Statistics collected since : (000 01:49:20) Fri Sep 12 11:43:12 2014
42 client_packets_sent 281293
43 client_packets_recv 296317
44 node_packets_sent 452387
45 node_packets_recv 182394
46 keepalive_packets_sent 3927
47 keepalive_packets_recv 3928
73 pending_childwrite_calls 0
76 total_ro_delegations 2
78 hop_count_buckets: 42816 5464 26 1 0 0 0 0 0 0 0 0 0 0 0 0
79 lock_buckets: 9 165 14 15 7 2 2 0 0 0 0 0 0 0 0 0
80 locks_latency MIN/AVG/MAX 0.000685/0.160302/6.369342 sec out of 214
81 reclock_ctdbd MIN/AVG/MAX 0.004940/0.004969/0.004998 sec out of 2
82 reclock_recd MIN/AVG/MAX 0.000000/0.000000/0.000000 sec out of 0
83 call_latency MIN/AVG/MAX 0.000006/0.000719/4.562991 sec out of 126626
84 childwrite_latency MIN/AVG/MAX 0.014527/0.014527/0.014527 sec out of 1
89 <title>CTDB version</title>
91 Version of the ctdb protocol used by the node.
96 <title>Current time of statistics</title>
98 Time when the statistics are generated.
101 This is useful when collecting statistics output periodically
107 <title>Statistics collected since</title>
109 Time when ctdb was started or the last time statistics was reset.
110 The output shows the duration and the timestamp.
115 <title>num_clients</title>
117 Number of processes currently connected to CTDB's unix socket.
118 This includes recovery daemon, ctdb tool and samba processes
124 <title>frozen</title>
126 1 if the the databases are currently frozen, 0 otherwise.
131 <title>recovering</title>
133 1 if recovery is active, 0 otherwise.
138 <title>num_recoveries</title>
140 Number of recoveries since the start of ctdb or since the last
146 <title>client_packets_sent</title>
148 Number of packets sent to client processes via unix domain socket.
153 <title>client_packets_recv</title>
155 Number of packets received from client processes via unix domain socket.
160 <title>node_packets_sent</title>
162 Number of packets sent to the other nodes in the cluster via TCP.
167 <title>node_packets_recv</title>
169 Number of packets received from the other nodes in the cluster via TCP.
174 <title>keepalive_packets_sent</title>
176 Number of keepalive messages sent to other nodes.
179 CTDB periodically sends keepalive messages to other nodes.
180 See <citetitle>KeepaliveInterval</citetitle> tunable in
181 <citerefentry><refentrytitle>ctdb-tunables</refentrytitle>
182 <manvolnum>7</manvolnum></citerefentry> for more details.
187 <title>keepalive_packets_recv</title>
189 Number of keepalive messages received from other nodes.
196 This section lists various types of messages processed which
197 originated from other nodes via TCP.
201 <title>req_call</title>
203 Number of REQ_CALL messages from the other nodes.
208 <title>reply_call</title>
210 Number of REPLY_CALL messages from the other nodes.
215 <title>req_dmaster</title>
217 Number of REQ_DMASTER messages from the other nodes.
222 <title>reply_dmaster</title>
224 Number of REPLY_DMASTER messages from the other nodes.
229 <title>reply_error</title>
231 Number of REPLY_ERROR messages from the other nodes.
236 <title>req_message</title>
238 Number of REQ_MESSAGE messages from the other nodes.
243 <title>req_control</title>
245 Number of REQ_CONTROL messages from the other nodes.
250 <title>reply_control</title>
252 Number of REPLY_CONTROL messages from the other nodes.
259 <title>client</title>
261 This section lists various types of messages processed which
262 originated from clients via unix domain socket.
266 <title>req_call</title>
268 Number of REQ_CALL messages from the clients.
273 <title>req_message</title>
275 Number of REQ_MESSAGE messages from the clients.
280 <title>req_control</title>
282 Number of REQ_CONTROL messages from the clients.
289 <title>timeouts</title>
291 This section lists timeouts occurred when sending various messages.
297 Number of timeouts for REQ_CALL messages.
302 <title>control</title>
304 Number of timeouts for REQ_CONTROL messages.
309 <title>traverse</title>
311 Number of timeouts for database traverse operations.
319 This section lists locking statistics.
323 <title>num_calls</title>
325 Number of completed lock calls. This includes database locks
331 <title>num_current</title>
333 Number of scheduled lock calls. This includes database locks
339 <title>num_pending</title>
341 Number of queued lock calls. This includes database locks and
347 <title>num_failed</title>
349 Number of failed lock calls. This includes database locks and
357 <title>total_calls</title>
359 Number of req_call messages processed from clients. This number
360 should be same as client --> req_call.
365 <title>pending_calls</title>
367 Number of req_call messages which are currenly being processed.
368 This number indicates the number of record migrations in flight.
373 <title>childwrite_calls</title>
375 Number of record update calls. Record update calls are used to
376 update a record under a transaction.
381 <title>pending_childwrite_calls</title>
383 Number of record update calls currently active.
388 <title>memory_used</title>
390 The amount of memory in bytes currently used by CTDB using
391 talloc. This includes all the memory used for CTDB's internal
392 data structures. This does not include the memory mapped TDB
398 <title>max_hop_count</title>
400 The maximum number of hops required for a record migration request
401 to obtain the record. High numbers indicate record contention.
406 <title>total_ro_delegations</title>
408 Number of readonly delegations created.
413 <title>total_ro_revokes</title>
415 Number of readonly delegations that were revoked. The difference
416 between total_ro_revokes and total_ro_delegations gives the
417 number of currently active readonly delegations.
422 <title>hop_count_buckets</title>
424 Distribution of migration requests based on hop counts values.
425 Buckets are 1, < 4, < 8, < 16, < 32, < 64, <
426 128, < 256, < 512, ≥ 512.
431 <title>lock_buckets</title>
433 Distribution of record lock requests based on time required to
434 obtain locks. Buckets are < 1ms, < 10ms, < 100ms,
435 < 1s, < 2s, < 4s, < 8s, < 16s, < 32s, <
441 <title>locks_latency</title>
443 The minimum, the average and the maximum time (in seconds)
444 required to obtain record locks.
449 <title>reclock_ctdbd</title>
451 The minimum, the average and the maximum time (in seconds)
452 required to check if recovery lock is still held by recovery
453 daemon when recovery mode is changed. This check is done in ctdb daemon.
458 <title>reclock_recd</title>
460 The minimum, the average and the maximum time (in seconds)
461 required to check if recovery lock is still held by recovery
462 daemon during recovery. This check is done in recovery daemon.
467 <title>call_latency</title>
469 The minimum, the average and the maximum time (in seconds) required
470 to process a REQ_CALL message from client. This includes the time
471 required to migrate a record from remote node, if the record is
472 not available on the local node.
477 <title>childwrite_latency</title>
478 <para>Default: 0</para>
480 The minimum, the average and the maximum time (in seconds)
481 required to update records under a transaction.
487 <title>DATABASE STATISTICS</title>
490 CTDB maintains per database statistics about important operations.
491 See the <citerefentry><refentrytitle>ctdb</refentrytitle>
492 <manvolnum>1</manvolnum></citerefentry> command
493 <command>dbstatistics</command> for displaying database statistics.
497 <title>Example: ctdb dbstatistics notify_index.tdb</title>
499 DB Statistics: notify_index.tdb
507 hop_count_buckets: 9890 5454 26 1 0 0 0 0 0 0 0 0 0 0 0 0
508 lock_buckets: 4 117 10 0 0 0 0 0 0 0 0 0 0 0 0 0
509 locks_latency MIN/AVG/MAX 0.000683/0.004198/0.014730 sec out of 131
511 Count:7 Key:2f636c75737465726673
512 Count:18 Key:2f636c757374657266732f64617461
513 Count:7 Key:2f636c757374657266732f646174612f636c69656e7473
518 <title>DB Statistics</title>
520 Name of the database.
525 <title>ro_delegations</title>
527 Number of readonly delegations created in the database.
532 <title>ro_revokes</title>
534 Number of readonly delegations revoked. The difference in
535 ro_delegations and ro_revokes indicates the currently active
536 readonly delegations.
543 This section lists locking statistics.
549 Number of completed lock calls. This includes database locks
555 <title>failed</title>
557 Number of failed lock calls. This includes database locks and
563 <title>current</title>
565 Number of scheduled lock calls. This includes database locks
571 <title>pending</title>
573 Number of queued lock calls. This includes database locks and
581 <title>hop_count_buckets</title>
583 Distribution of migration requests based on hop counts values.
584 Buckets are 1, < 4, < 8, < 16, < 32, < 64, <
585 128, < 256, < 512, ≥ 512.
590 <title>lock_buckets</title>
592 Distribution of record lock requests based on time required to
593 obtain locks. Buckets are < 1ms, < 10ms, < 100ms,
594 < 1s, < 2s, < 4s, < 8s, < 16s, < 32s, <
600 <title>locks_latency</title>
602 The minimum, the average and the maximum time (in seconds)
603 required to obtain record locks.
608 <title>Num Hot Keys</title>
610 Number of contended records determined by hop count. CTDB keeps
611 track of top 10 hot records and the output shows hex encoded
612 keys for the hot records.
618 <title>SEE ALSO</title>
620 <citerefentry><refentrytitle>ctdb</refentrytitle>
621 <manvolnum>1</manvolnum></citerefentry>,
623 <citerefentry><refentrytitle>ctdbd</refentrytitle>
624 <manvolnum>1</manvolnum></citerefentry>,
626 <citerefentry><refentrytitle>ctdb-tunables</refentrytitle>
627 <manvolnum>7</manvolnum></citerefentry>,
629 <ulink url="http://ctdb.samba.org/"/>
636 This documentation was written by
644 <holder>Andrew Tridgell</holder>
645 <holder>Ronnie Sahlberg</holder>
649 This program is free software; you can redistribute it and/or
650 modify it under the terms of the GNU General Public License as
651 published by the Free Software Foundation; either version 3 of
652 the License, or (at your option) any later version.
655 This program is distributed in the hope that it will be
656 useful, but WITHOUT ANY WARRANTY; without even the implied
657 warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
658 PURPOSE. See the GNU General Public License for more details.
661 You should have received a copy of the GNU General Public
662 License along with this program; if not, see
663 <ulink url="http://www.gnu.org/licenses"/>.