--- name: "ctdb-statistics" section: "7" platform: "linux" package: "ctdb" version: "2:4.22.11+dfsg-0+deb13u1" release: "Debian 13 (Trixie)" platforms: ["linux"] url: "https://new.carta.tech/ctdb-statistics" --- # ctdb-statistics(7) CTDB statistics output ## NAME ctdb-statistics - CTDB statistics output ## OVERALL STATISTICS CTDB maintains information about various messages communicated and some of the important operations per node. See the [**ctdb**(1)](/ctdb/1.md) commands **statistics** and **statisticsreset** for displaying statistics. ### Example: ctdb statistics ``` CTDB version 1 Current time of statistics : Fri Sep 12 13:32:32 2014 Statistics collected since : (000 01:49:20) Fri Sep 12 11:43:12 2014 num_clients 6 frozen 0 recovering 0 num_recoveries 2 client_packets_sent 281293 client_packets_recv 296317 node_packets_sent 452387 node_packets_recv 182394 keepalive_packets_sent 3927 keepalive_packets_recv 3928 node req_call 48605 reply_call 1 req_dmaster 23404 reply_dmaster 24917 reply_error 0 req_message 958 req_control 197513 reply_control 153705 client req_call 130866 req_message 770 req_control 168921 timeouts call 0 control 0 traverse 0 locks num_calls 220 num_current 0 num_pending 0 num_failed 0 total_calls 130866 pending_calls 0 childwrite_calls 1 pending_childwrite_calls 0 memory_used 334490 max_hop_count 18 total_ro_delegations 2 total_ro_revokes 2 hop_count_buckets: 42816 5464 26 1 0 0 0 0 0 0 0 0 0 0 0 0 lock_buckets: 9 165 14 15 7 2 2 0 0 0 0 0 0 0 0 0 locks_latency MIN/AVG/MAX 0.000685/0.160302/6.369342 sec out of 214 reclock_ctdbd MIN/AVG/MAX 0.004940/0.004969/0.004998 sec out of 2 reclock_recd MIN/AVG/MAX 0.000000/0.000000/0.000000 sec out of 0 call_latency MIN/AVG/MAX 0.000006/0.000719/4.562991 sec out of 126626 childwrite_latency MIN/AVG/MAX 0.014527/0.014527/0.014527 sec out of 1 ``` ### CTDB version Version of the ctdb protocol used by the node. ### Current time of statistics Time when the statistics are generated. This is useful when collecting statistics output periodically for post-processing. ### Statistics collected since Time when ctdb was started or the last time statistics was reset. The output shows the duration and the timestamp. ### num\_clients Number of processes currently connected to CTDB's unix socket. This includes recovery daemon, ctdb tool and samba processes (smbd, winbindd). ### frozen 1 if the databases are currently frozen, 0 otherwise. ### recovering 1 if recovery is active, 0 otherwise. ### num\_recoveries Number of recoveries since the start of ctdb or since the last statistics reset. ### client\_packets\_sent Number of packets sent to client processes via unix domain socket. ### client\_packets\_recv Number of packets received from client processes via unix domain socket. ### node\_packets\_sent Number of packets sent to the other nodes in the cluster via TCP. ### node\_packets\_recv Number of packets received from the other nodes in the cluster via TCP. ### keepalive\_packets\_sent Number of keepalive messages sent to other nodes. CTDB periodically sends keepalive messages to other nodes. See KeepaliveInterval tunable in [**ctdb-tunables**(7)](/ctdb-tunables/7.md) for more details. ### keepalive\_packets\_recv Number of keepalive messages received from other nodes. ### node This section lists various types of messages processed which originated from other nodes via TCP. **req\_call** Number of REQ\_CALL messages from the other nodes. **reply\_call** Number of REPLY\_CALL messages from the other nodes. **req\_dmaster** Number of REQ\_DMASTER messages from the other nodes. **reply\_dmaster** Number of REPLY\_DMASTER messages from the other nodes. **reply\_error** Number of REPLY\_ERROR messages from the other nodes. **req\_message** Number of REQ\_MESSAGE messages from the other nodes. **req\_control** Number of REQ\_CONTROL messages from the other nodes. **reply\_control** Number of REPLY\_CONTROL messages from the other nodes. **req\_tunnel** Number of REQ\_TUNNEL messages from the other nodes. ### client This section lists various types of messages processed which originated from clients via unix domain socket. **req\_call** Number of REQ\_CALL messages from the clients. **req\_message** Number of REQ\_MESSAGE messages from the clients. **req\_control** Number of REQ\_CONTROL messages from the clients. **req\_tunnel** Number of REQ\_TUNNEL messages from the clients. ### timeouts This section lists timeouts occurred when sending various messages. **call** Number of timeouts for REQ\_CALL messages. **control** Number of timeouts for REQ\_CONTROL messages. **traverse** Number of timeouts for database traverse operations. ### locks This section lists locking statistics. **num\_calls** Number of completed lock calls. This includes database locks and record locks. **num\_current** Number of scheduled lock calls. This includes database locks and record locks. **num\_pending** Number of queued lock calls. This includes database locks and record locks. **num\_failed** Number of failed lock calls. This includes database locks and record locks. ### total\_calls Number of req\_call messages processed from clients. This number should be same as client --\> req\_call. ### pending\_calls Number of req\_call messages which are currently being processed. This number indicates the number of record migrations in flight. ### childwrite\_calls Number of record update calls. Record update calls are used to update a record under a transaction. ### pending\_childwrite\_calls Number of record update calls currently active. ### memory\_used The amount of memory in bytes currently used by CTDB using talloc. This includes all the memory used for CTDB's internal data structures. This does not include the memory mapped TDB databases. ### max\_hop\_count The maximum number of hops required for a record migration request to obtain the record. High numbers indicate record contention. ### total\_ro\_delegations Number of readonly delegations created. ### total\_ro\_revokes Number of readonly delegations that were revoked. The difference between total\_ro\_revokes and total\_ro\_delegations gives the number of currently active readonly delegations. ### hop\_count\_buckets Distribution of migration requests based on hop counts values. Buckets are 0, \< 2, \< 4, \< 8, \< 16, \< 32, \< 64, \< 128, \< 256, \< 512, \< 1024, \< 2048, \< 4096, \< 8192, \< 16384, ≥ 16384. ### lock\_buckets Distribution of record lock requests based on time required to obtain locks. Buckets are \< 1ms, \< 10ms, \< 100ms, \< 1s, \< 2s, \< 4s, \< 8s, \< 16s, \< 32s, \< 64s, ≥ 64s. ### locks\_latency The minimum, the average and the maximum time (in seconds) required to obtain record locks. ### reclock\_ctdbd The minimum, the average and the maximum time (in seconds) required to check if recovery lock is still held by recovery daemon when recovery mode is changed. This check is done in ctdb daemon. ### reclock\_recd The minimum, the average and the maximum time (in seconds) required to check if recovery lock is still held by recovery daemon during recovery. This check is done in recovery daemon. ### call\_latency The minimum, the average and the maximum time (in seconds) required to process a REQ\_CALL message from client. This includes the time required to migrate a record from remote node, if the record is not available on the local node. ### childwrite\_latency Default: 0 The minimum, the average and the maximum time (in seconds) required to update records under a transaction. ## DATABASE STATISTICS CTDB maintains per database statistics about important operations. See the [**ctdb**(1)](/ctdb/1.md) command **dbstatistics** for displaying database statistics. ### Example: ctdb dbstatistics notify\_index.tdb ``` DB Statistics: notify_index.tdb ro_delegations 0 ro_revokes 0 locks total 131 failed 0 current 0 pending 0 hop_count_buckets: 9890 5454 26 1 0 0 0 0 0 0 0 0 0 0 0 0 lock_buckets: 4 117 10 0 0 0 0 0 0 0 0 0 0 0 0 0 locks_latency MIN/AVG/MAX 0.000683/0.004198/0.014730 sec out of 131 Num Hot Keys: 3 Count:7 Key:2f636c75737465726673 Count:18 Key:2f636c757374657266732f64617461 Count:7 Key:2f636c757374657266732f646174612f636c69656e7473 ``` ### DB Statistics Name of the database. ### ro\_delegations Number of readonly delegations created in the database. ### ro\_revokes Number of readonly delegations revoked. The difference in ro\_delegations and ro\_revokes indicates the currently active readonly delegations. ### locks This section lists locking statistics. **total** Number of completed lock calls. This includes database locks and record locks. **failed** Number of failed lock calls. This includes database locks and record locks. **current** Number of scheduled lock calls. This includes database locks and record locks. **pending** Number of queued lock calls. This includes database locks and record locks. ### hop\_count\_buckets Distribution of migration requests based on hop counts values. Buckets are 0, \< 2, \< 4, \< 8, \< 16, \< 32, \< 64, \< 128, \< 256, \< 512, \< 1024, \< 2048, \< 4096, \< 8192, \< 16384, ≥ 16384. ### lock\_buckets Distribution of record lock requests based on time required to obtain locks. Buckets are \< 1ms, \< 10ms, \< 100ms, \< 1s, \< 2s, \< 4s, \< 8s, \< 16s, \< 32s, \< 64s, ≥ 64s. ### locks\_latency The minimum, the average and the maximum time (in seconds) required to obtain record locks. ### Num Hot Keys Number of contended records determined by hop count. CTDB keeps track of top 10 hot records and the output shows hex encoded keys for the hot records. ## SEE ALSO [**ctdb**(1)](/ctdb/1.md), [**ctdbd**(1)](/ctdbd/1.md), [**ctdb-tunables**(7)](/ctdb-tunables/7.md), **http://ctdb.samba.org/** ## AUTHOR This documentation was written by Amitay Isaacs, Martin Schwenke ## COPYRIGHT Copyright © 2007 Andrew Tridgell, Ronnie Sahlberg\ This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, see **http://www.gnu.org/licenses**.