MySQL 5.5 の簡易チューニング

「mysqltuner」を使用することで、現状の改善点を出力してくれます。

Redhat系ディストリビューションならEPELレポジトリを使ってインストールすることができます。

# yum install mysqltuner

インストールが完了後、下記コマンドで実行する。
赤字は任意で変更！

# mysqltuner --user *user* --pass *password*
 >>  MySQLTuner 1.2.0 - Major Hayden 
 >>  Bug reports, feature requests, and downloads at http://mysqltuner.com/
 >>  Run with '--help' for additional options and output filtering
[OK] Logged in using credentials passed on the command line

-------- General Statistics --------------------------------------------------
[--] Skipped version check for MySQLTuner script
[OK] Currently running supported MySQL version 5.5.38-log
[OK] Operating on 64-bit architecture

-------- Storage Engine Statistics -------------------------------------------
[--] Status: +Archive -BDB -Federated +InnoDB -ISAM -NDBCluster 
[--] Data in InnoDB tables: 12M (Tables: 38)
[--] Data in MyISAM tables: 11M (Tables: 8)
[--] Data in PERFORMANCE_SCHEMA tables: 0B (Tables: 17)
[!!] Total fragmented tables: 7

-------- Security Recommendations  -------------------------------------------
[OK] All database users have passwords assigned

-------- Performance Metrics -------------------------------------------------
[--] Up for: 2d 17h 5m 37s (7M q [29.946 qps], 1K conn, TX: 7B, RX: 575M)
[--] Reads / Writes: 98% / 2%
[--] Total buffers: 4.1G global + 8.8M per thread (256 max threads)
[OK] Maximum possible memory usage: 6.2G (9% of installed RAM)
[OK] Slow queries: 0% (0/7M)
[OK] Highest usage of available connections: 3% (9/256)
[OK] Key buffer size / total MyISAM indexes: 8.0M/10.8M
[OK] Key buffer hit rate: 100.0% (881M cached / 45K reads)
[OK] Query cache efficiency: 65.9% (4M cached / 6M selects)
[!!] Query cache prunes per day: 143882
[OK] Sorts requiring temporary tables: 0% (0 temp sorts / 3K sorts)
[OK] Temporary tables created on disk: 0% (0 on disk / 279 total)
[OK] Thread cache hit rate: 99% (9 created / 1K connections)
[OK] Table cache hit rate: 93% (93 open / 100 opened)
[OK] Open file limit used: 4% (73/1K)
[OK] Table locks acquired immediately: 99% (2M immediate / 2M locks)
[OK] InnoDB data size / buffer pool: 12.6M/4.0G

-------- Recommendations -----------------------------------------------------
General recommendations:
    Run OPTIMIZE TABLE to defragment tables for better performance
Variables to adjust:
    query_cache_size (> 16M)

基本的には my.cnf ファイルに対して修正・追加などを行う。
「Run OPTIMIZE TABLE to defragment tables for better performance」と出てるのですが、下記コマンドで自動実行が出来る。

# systemctl stop httpd
# mysqlcheck -u root -p --auto-repair --optimize --all-databases
# systemctl start httpd