Administrace komentářů

Zdravim, mam MySQL v 3 uzlech pomoci master-master replikace Percona xtradb cluster.
Vse beha v poho az do chvile kdy po nejake dobe insertne zaznam do db ktera ma neco kolem 300 zaznamu. V tuto chvili se postupne zatizi vsechny tri uzle replikace a prestanou reagovat na par desitek vterin repsektive kousne se cela aplikace.
Ale nad touto tabulkou se provadi relativne dost SELECTu radove desitky za vterinu.

Myslim ze to muze delat velka hodnota query-cache-size ale s mensi hodnotou bylo zase hodne prunes per day.
Dokaze nekdo prosim nakopnout spravnym smerem co hledat?

V logu mam pak neco v tomto duchu (Uvedena table v logu nize nesouvisi prave s tou ve ktere se provedl insert)

*** Priority TRANSACTION:
TRANSACTION 393262833, ACTIVE 0 sec starting index read
mysql tables in use 1, locked 1
1 lock struct(s), heap size 360, 0 row lock(s)
MySQL thread id 7, OS thread handle 0x7f255962e700, query id 299104427 invalidating query cache entries (table)

*** Victim TRANSACTION:
TRANSACTION 393257917, ACTIVE 114 sec
mysql tables in use 1, locked 1
2 lock struct(s), heap size 360, 1 row lock(s), undo log entries 1
MySQL thread id 25482552, OS thread handle 0x7f252e134700, query id 299095466 localhost 127.0.0.1 database_sys wsrep in pre-commit stage
UPDATE `table` SET `record`=1.5655388889 WHERE (`table`.`id` = 10776)
*** WAITING FOR THIS LOCK TO BE GRANTED:
RECORD LOCKS space id 4039 page no 126 n bits 176 index `PRIMARY` of table `database`.`table` trx id 393257917 lock_mode X locks rec but not gap
2015-02-26 22:47:53 58270 [Note] WSREP: cluster conflict due to high priority abort for threads:
2015-02-26 22:47:53 58270 [Note] WSREP: Winning thread:
   THD: 7, mode: applier, state: executing, conflict: no conflict, seqno: 33153378
   SQL: (null)
2015-02-26 22:47:53 58270 [Note] WSREP: Victim thread:
   THD: 25482552, mode: local, state: committing, conflict: no conflict, seqno: -1
   SQL: UPDATE `table` SET `record`=1.5655388889 WHERE (`table`.`id` = 10776)

Pro MySQL je nasledujici konfigurace

[mysqld]
innodb_use_native_aio=0
datadir = /var/lib/mysql
pid-file = /var/run/mysqld/mysqld.pid
key-buffer-size = 32M
myisam-recover = FORCE,BACKUP
max-allowed-packet = 16M
max-connect-errors = 1000000
innodb = FORCE
tmp-table-size = 32M
max-heap-table-size = 32M
max-connections = 500
thread-cache-size = 50
open-files-limit = 65535
table-definition-cache = 1024
table-open-cache = 2048
log-error = /var/log/mysql/error.log
log-queries-not-using-indexes = 0
slow-query-log = 0
slow-query-log-file = /var/log/mysql/slow.log

# CACHES AND LIMITS #
#table_cache                    = 16000
tmp-table-size                 = 256M
max-heap-table-size            = 256M
query-cache-type               = 1
query-cache-size               = 2048M
max-connections                = 2000
thread-cache-size              = 50
open-files-limit               = 65535
table-definition-cache         = 8000
table-open-cache               = 8000
key_buffer_size                 = 256M
join_buffer_size                = 512k
thread_cache_size               = 15000
table_definition_cache          = 16384
table_open_cache                = 16384
innodb_write_io_threads         = 16
innodb_read_io_threads          = 16
back_log                        = 2048


# INNODB #
innodb_lock_wait_timeout        = 60
innodb_buffer_pool_instances    = 8
innodb_rollback_on_timeout      = 0
innodb-flush-method            = O_DIRECT
innodb-log-files-in-group      = 2
innodb-log-file-size           = 128M
#innodb-flush-log-at-trx-commit = 1
innodb-file-per-table          = 1
innodb-buffer-pool-size        = 4096M
innodb-flush-log-at-trx-commit = 0

[--] Up for: 18d 2h 26m 48s (258M q [165.038 qps], 23M conn, TX: 164B, RX: 39B)
[--] Reads / Writes: 69% / 31%
[--] Total buffers: 6.5G global + 1.4M per thread (800 max threads)
[OK] Maximum possible memory usage: 7.6G (48% of installed RAM)
[OK] Slow queries: 0% (4K/258M)
[OK] Highest usage of available connections: 34% (275/800)
[OK] Key buffer size / total MyISAM indexes: 256.0M/102.0K
[OK] Key buffer hit rate: 100.0% (171M cached / 4 reads)
[OK] Query cache efficiency: 46.5% (89M cached / 192M selects)
[OK] Query cache prunes per day: 0
[OK] Sorts requiring temporary tables: 0% (3K temp sorts / 15M sorts)
[OK] Temporary tables created on disk: 0% (1K on disk / 11M total)
[OK] Thread cache hit rate: 99% (308 created / 23M connections)
[OK] Table cache hit rate: 87% (3K open / 4K opened)
[OK] Open file limit used: 0% (18/33K)
[OK] Table locks acquired immediately: 99% (166M immediate / 166M locks)
[!!] InnoDB  buffer pool / data size: 4.0G/5.0G
[OK] InnoDB log waits: 0

[--] Up for: 18d 2h 26m 48s (258M q [165.038 qps], 23M conn, TX: 164B, RX: 39B)
[--] Reads / Writes: 69% / 31%
[--] Total buffers: 6.5G global + 1.4M per thread (800 max threads)
[OK] Maximum possible memory usage: 7.6G (48% of installed RAM)
[OK] Slow queries: 0% (4K/258M)
[OK] Highest usage of available connections: 34% (275/800)
[OK] Key buffer size / total MyISAM indexes: 256.0M/102.0K
[OK] Key buffer hit rate: 100.0% (171M cached / 4 reads)
[OK] Query cache efficiency: 46.5% (89M cached / 192M selects)
[OK] Query cache prunes per day: 0
[OK] Sorts requiring temporary tables: 0% (3K temp sorts / 15M sorts)
[OK] Temporary tables created on disk: 0% (1K on disk / 11M total)
[OK] Thread cache hit rate: 99% (308 created / 23M connections)
[OK] Table cache hit rate: 87% (3K open / 4K opened)
[OK] Open file limit used: 0% (18/33K)
[OK] Table locks acquired immediately: 99% (166M immediate / 166M locks)
[!!] InnoDB  buffer pool / data size: 4.0G/5.0G
[OK] InnoDB log waits: 0