0、首先查看当前是否开启慢查询:
(1)快速办法,运行sql语句
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1 | show VARIABLES like "%slow%" |
(2)直接去my.conf中查看。
my.conf中的配置(放在[mysqld]下的下方加入)
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12345 | [mysqld] log-slow-queries = /usr/local/mysql/var/slowquery.log long_query_time = 1 #单位是秒 log-queries-not-using-indexes |
使用sql语句来修改:不能按照my.conf中的项来修改的。修改通过"show VARIABLES like "%slow%" "
语句列出来的变量,运行如下sql:
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123 | set global log_slow_queries = ON ; set global slow_query_log = ON ; set global long_query_time=0.1; #设置大于0.1s的sql语句记录下来 |
慢查询日志文件的信息格式:
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123 | # Time: 130905 14:15:59 时间是2013年9月5日 14:15:59(前面部分容易看错哦,乍看以为是时间戳) # User@Host: root[root] @ [183.239.28.174] 请求mysql服务器的客户端ip # Query_time: 0.735883 Lock_time: 0.000078 Rows_sent: 262 Rows_examined: 262 这里表示执行用时多少秒,0.735883秒,1秒等于1000毫秒 |
SET timestamp=1378361759; 这目前我还不知道干嘛用的
show tables from `test_db`; 这个就是关键信息,指明了当时执行的是这条语句
1、MySQL 慢查询日志分析
pt-query-digest分析慢查询日志
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1 | pt-query-digest –report slow.log |
报告最近半个小时的慢查询:
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1 | pt-query-digest –report –since 1800s slow.log |
报告一个时间段的慢查询:
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1 | pt-query-digest –report –since ‘2013-02-10 21:48:59′ – until ‘2013-02-16 02:33:50′ slow.log |
报告只含select语句的慢查询:
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1 | pt-query-digest –filter ‘$event->{fingerprint} =~ m/^ select /i ' slow.log |
报告针对某个用户的慢查询:
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1 | pt-query-digest –filter ‘($event->{user} || “”) =~ m/^root /i ' slow.log |
报告所有的全表扫描或full join的慢查询:
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1 | pt-query-digest –filter ‘(($event->{Full_scan} || “”) eq “ yes ”) || (($event->{Full_join} || “”) eq “ yes ”)' slow.log |
2、将慢查询日志的分析结果可视化
Query-Digest-UI
其实,这是一个非常简单和直接的工具,浏览和统计Mysql慢查询,基于AJAX的Web界面。
配置Query-Digest-UI:
下载:
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12 | wget https: //nodeload .github.com /kormoc/Query-Digest-UI/zip/master unzip Query-Digest-UI-master.zip |
查询分析结果可视化步骤如下:
(1)创建相关数据库表
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-- install.sql -- Create the database needed for the Query-Digest-UI DROP DATABASE IF EXISTS slow_query_log; CREATE DATABASE slow_query_log; USE slow_query_log; -- Create the global query review table CREATE TABLE `global_query_review` ( `checksum` bigint (20) unsigned NOT NULL , `fingerprint` text NOT NULL , `sample` longtext NOT NULL , `first_seen` datetime DEFAULT NULL , `last_seen` datetime DEFAULT NULL , `reviewed_by` varchar (20) DEFAULT NULL , `reviewed_on` datetime DEFAULT NULL , `comments` text, `reviewed_status` varchar (24) DEFAULT NULL , PRIMARY KEY (`checksum`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; -- Create the historical query review table CREATE TABLE `global_query_review_history` ( `hostname_max` varchar (64) NOT NULL , `db_max` varchar (64) DEFAULT NULL , `checksum` bigint (20) unsigned NOT NULL , `sample` longtext NOT NULL , `ts_min` datetime NOT NULL DEFAULT '0000-00-00 00:00:00' , `ts_max` datetime NOT NULL DEFAULT '0000-00-00 00:00:00' , `ts_cnt` float DEFAULT NULL , `Query_time_sum` float DEFAULT NULL , `Query_time_min` float DEFAULT NULL , `Query_time_max` float DEFAULT NULL , `Query_time_pct_95` float DEFAULT NULL , `Query_time_stddev` float DEFAULT NULL , `Query_time_median` float DEFAULT NULL , `Lock_time_sum` float DEFAULT NULL , `Lock_time_min` float DEFAULT NULL , `Lock_time_max` float DEFAULT NULL , `Lock_time_pct_95` float DEFAULT NULL , `Lock_time_stddev` float DEFAULT NULL , `Lock_time_median` float DEFAULT NULL , `Rows_sent_sum` float DEFAULT NULL , `Rows_sent_min` float DEFAULT NULL , `Rows_sent_max` float DEFAULT NULL , `Rows_sent_pct_95` float DEFAULT NULL , `Rows_sent_stddev` float DEFAULT NULL , `Rows_sent_median` float DEFAULT NULL , `Rows_examined_sum` float DEFAULT NULL , `Rows_examined_min` float DEFAULT NULL , `Rows_examined_max` float DEFAULT NULL , `Rows_examined_pct_95` float DEFAULT NULL , `Rows_examined_stddev` float DEFAULT NULL , `Rows_examined_median` float DEFAULT NULL , `Rows_affected_sum` float DEFAULT NULL , `Rows_affected_min` float DEFAULT NULL , `Rows_affected_max` float DEFAULT NULL , `Rows_affected_pct_95` float DEFAULT NULL , `Rows_affected_stddev` float DEFAULT NULL , `Rows_affected_median` float DEFAULT NULL , `Rows_read_sum` float DEFAULT NULL , `Rows_read_min` float DEFAULT NULL , `Rows_read_max` float DEFAULT NULL , `Rows_read_pct_95` float DEFAULT NULL , `Rows_read_stddev` float DEFAULT NULL , `Rows_read_median` float DEFAULT NULL , `Merge_passes_sum` float DEFAULT NULL , `Merge_passes_min` float DEFAULT NULL , `Merge_passes_max` float DEFAULT NULL , `Merge_passes_pct_95` float DEFAULT NULL , `Merge_passes_stddev` float DEFAULT NULL , `Merge_passes_median` float DEFAULT NULL , `InnoDB_IO_r_ops_min` float DEFAULT NULL , `InnoDB_IO_r_ops_max` float DEFAULT NULL , `InnoDB_IO_r_ops_pct_95` float DEFAULT NULL , `InnoDB_IO_r_bytes_pct_95` float DEFAULT NULL , `InnoDB_IO_r_bytes_stddev` float DEFAULT NULL , `InnoDB_IO_r_bytes_median` float DEFAULT NULL , `InnoDB_IO_r_wait_min` float DEFAULT NULL , `InnoDB_IO_r_wait_max` float DEFAULT NULL , `InnoDB_IO_r_wait_pct_95` float DEFAULT NULL , `InnoDB_IO_r_ops_stddev` float DEFAULT NULL , `InnoDB_IO_r_ops_median` float DEFAULT NULL , `InnoDB_IO_r_bytes_min` float DEFAULT NULL , `InnoDB_IO_r_bytes_max` float DEFAULT NULL , `InnoDB_IO_r_wait_stddev` float DEFAULT NULL , `InnoDB_IO_r_wait_median` float DEFAULT NULL , `InnoDB_rec_lock_wait_min` float DEFAULT NULL , `InnoDB_rec_lock_wait_max` float DEFAULT NULL , `InnoDB_rec_lock_wait_pct_95` float DEFAULT NULL , `InnoDB_rec_lock_wait_stddev` float DEFAULT NULL , `InnoDB_rec_lock_wait_median` float DEFAULT NULL , `InnoDB_queue_wait_min` float DEFAULT NULL , `InnoDB_queue_wait_max` float DEFAULT NULL , `InnoDB_queue_wait_pct_95` float DEFAULT NULL , `InnoDB_queue_wait_stddev` float DEFAULT NULL , `InnoDB_queue_wait_median` float DEFAULT NULL , `InnoDB_pages_distinct_min` float DEFAULT NULL , `InnoDB_pages_distinct_max` float DEFAULT NULL , `InnoDB_pages_distinct_pct_95` float DEFAULT NULL , `InnoDB_pages_distinct_stddev` float DEFAULT NULL , `InnoDB_pages_distinct_median` float DEFAULT NULL , `QC_Hit_cnt` float DEFAULT NULL , `QC_Hit_sum` float DEFAULT NULL , `Full_scan_cnt` float DEFAULT NULL , `Full_scan_sum` float DEFAULT NULL , `Full_join_cnt` float DEFAULT NULL , `Full_join_sum` float DEFAULT NULL , `Tmp_table_cnt` float DEFAULT NULL , `Tmp_table_sum` float DEFAULT NULL , `Filesort_cnt` float DEFAULT NULL , `Filesort_sum` float DEFAULT NULL , `Tmp_table_on_disk_cnt` float DEFAULT NULL , `Tmp_table_on_disk_sum` float DEFAULT NULL , `Filesort_on_disk_cnt` float DEFAULT NULL , `Filesort_on_disk_sum` float DEFAULT NULL , `Bytes_sum` float DEFAULT NULL , `Bytes_min` float DEFAULT NULL , `Bytes_max` float DEFAULT NULL , `Bytes_pct_95` float DEFAULT NULL , `Bytes_stddev` float DEFAULT NULL , `Bytes_median` float DEFAULT NULL , UNIQUE KEY `hostname_max` (`hostname_max`,`checksum`,`ts_min`,`ts_max`), KEY `ts_min` (`ts_min`), KEY `checksum` (`checksum`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; |
(2)创建数据库账号
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12 | $ mysql -uroot -p -h 192.168.1.190 < install .sql $ mysql -uroot -p -h 192.168.1.190 -e "grant ALL ON slow_query_log.* to 'slowlog'@'%' IDENTIFIED BY '123456';" |
(3)配置Query-Digest-UI
修改数据库连接配置
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cd Query-Digest-UI cp config.php.example config.php vi config.php $reviewhost = array( // Replace hostname and database in this setting // use host= hostname ;port=portnum if not the default port 'dsn' => 'mysql:host=192.168.1.190;port=3306;dbname=slow_query_log' , 'user' => 'slowlog' , 'password' => '123456' , // See http: //www .percona.com /doc/percona-toolkit/2 .1 /pt-query-digest .html #cmdoption-pt-query-digest--review 'review_table' => 'global_query_review' , // This table is optional. You don't need it, but you lose detailed stats // Set to a blank string to disable // See http: //www .percona.com /doc/percona-toolkit/2 .1 /pt-query-digest .html #cmdoption-pt-query-digest--review-history 'history_table' => 'global_query_review_history' , ); |
(4)使用pt-query-digest分析日志并将分析结果导入数据库
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pt-query-digest --user=slowlog \ --password=123456 \ --review h=192.168.1.190,D=slow_query_log,t=global_query_review \ --review- history h=192.168.1.190,D=slow_query_log,t=global_query_review_history\ --no-report --limit=0% \ --filter= " \$event->{Bytes} = length(\$event->{arg}) and \$event->{hostname}=\"$HOSTNAME\"" \ /usr/local/mysql/data/slow .log |