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Mysql5.6开启慢查询日志_MySQL

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Jun 01, 2016 pm 01:08 PM

[root@slave1 logs]# cat /etc/my.cnf [mysqld]basedir=/usr/local/mysql/  datadir=/usr/local/mysql/data/ user=mysql#打开慢查询日志slow_query_log=on#慢查询日志的位置slow_query_log_file=/usr/local/mysql/logs/mysql-slow#慢查询的基准线超过5s的查询将会被记录long_query_time=5# Disabling symbolic-links is recommended to prevent assorted security riskssymbolic-links=0log-bin=/usr/local/mysql/logs/mysql-binserver-id=1[mysqld_safe]log-error=/var/log/mysqld.logpid-file=/var/run/mysqld/mysqld.pid[mysql]socket=/var/lib/mysql/mysql.sock[root@slave1 logs]# /etc/init.d/mysqld restart[root@slave1 logs]# mysql -uroot -pmysql> show variables like '%query%';+------------------------------+----------------------------------+| Variable_name                | Value                            |+------------------------------+----------------------------------+| binlog_rows_query_log_events | OFF                              || ft_query_expansion_limit     | 20                               || have_query_cache             | YES                              || long_query_time              | 5.000000                         || query_alloc_block_size       | 8192                             || query_cache_limit            | 1048576                          || query_cache_min_res_unit     | 4096                             || query_cache_size             | 1048576                          || query_cache_type             | OFF                              || query_cache_wlock_invalidate | OFF                              || query_prealloc_size          | 8192                             || slow_query_log               | ON                               || slow_query_log_file          | /usr/local/mysql/logs/mysql-slow |+------------------------------+----------------------------------+[root@slave1 ~]# cat  /usr/local/mysql/logs/mysql-slow/usr/local/mysql/bin/mysqld, Version: 5.6.15-log (Source distribution). started with:Tcp port: 0  Unix socket: (null)Time                 Id Command    Argumentmysql> select 1;mysql> select sleep(3);mysql> select sleep(4);mysql> select sleep(5);mysql> select sleep(6);[root@slave1 logs]# cat mysql-slow /usr/local/mysql/bin/mysqld, Version: 5.6.15-log (Source distribution). started with:Tcp port: 0  Unix socket: (null)Time                 Id Command    Argument# Time: 140618 11:05:53# User@Host: root[root] @ localhost []  Id:     2# Query_time: 5.000229  Lock_time: 0.000000 Rows_sent: 1  Rows_examined: 0SET timestamp=1403060753;select sleep(5);# Time: 140618 11:06:01# User@Host: root[root] @ localhost []  Id:     2# Query_time: 5.000222  Lock_time: 0.000000 Rows_sent: 1  Rows_examined: 0SET timestamp=1403060761;select sleep(5);# Time: 140618 11:06:15# User@Host: root[root] @ localhost []  Id:     2# Query_time: 6.000216  Lock_time: 0.000000 Rows_sent: 1  Rows_examined: 0SET timestamp=1403060775;select sleep(6);[root@slave1 logs]# mysqldumpslow mysql-slow Reading mysql slow query log from mysql-slowCount: 3  Time=5.33s (16s)  Lock=0.00s (0s)  Rows=1.0 (3), root[root]@localhost  select sleep(N)	 #下载hackmysql.com 推出的一款日志分析工具 mysqlsla 。 [root@slave1 opt]# wget http://hackmysql.com/scripts/mysqlsla-2.03.tar.gz[root@slave1 opt]# ll mysqlsla-2.03.tar.gz -rw-r--r-- 1 root root 33674 Nov 11  2008 mysqlsla-2.03.tar.gz[root@slave1 opt]# tar -xf mysqlsla-2.03.tar.gz -C /usr/src/[root@slave1 opt]# cd /usr/src/mysqlsla-2.03/[root@slave1 mysqlsla-2.03]# yum install perl -y[root@slave1 mysqlsla-2.03]# yum install perl-devel -y[root@slave1 mysqlsla-2.03]# yum install perl-CPAN -y[root@slave1 mysqlsla-2.03]# yum install perl-Time-HiRes -y[root@slave1 mysqlsla-2.03]# perl Makefile.PL Checking if your kit is complete...Looks goodWriting Makefile for mysqlsla[root@slave1 mysqlsla-2.03]# makecp lib/mysqlsla.pm blib/lib/mysqlsla.pmcp bin/mysqlsla blib/script/mysqlsla/usr/bin/perl -MExtUtils::MY -e 'MY->fixin(shift)' -- blib/script/mysqlslaManifying blib/man3/mysqlsla.3pm[root@slave1 mysqlsla-2.03]# make installInstalling /usr/local/share/perl5/mysqlsla.pmInstalling /usr/local/share/man/man3/mysqlsla.3pmInstalling /usr/local/bin/mysqlslaAppending installation info to /usr/lib64/perl5/perllocal.pod第一次通过CPAN安装perl模块时，需要进行相关的配置，大部分配置采用默认值，一路回车即可#perl -MCPAN -e shell然后在下面的各个询问中可以改已经配置好的选项然后执行下面的命令保存CPAN>reload indexCPAN>reload cpan安装DBI模块CPAN>install DBI[root@slave1 mysqlsla-2.03]# mysqlsla -lt slow /usr/local/mysql/logs/mysql-slow Report for slow logs: /usr/local/mysql/logs/mysql-slow3 queries total, 1 uniqueSorted by 't_sum'Grand Totals: Time 16 s, Lock 0 s, Rows sent 3, Rows Examined 0______________________________________________________________________ 001 ___Count         : 3  (100.00%)Time          : 16.000667 s total, 5.333556 s avg, 5.000222 s to 6.000216 s max  (100.00%)Lock Time (s) : 0 total, 0 avg, 0 to 0 max  (0.00%)Rows sent     : 1 avg, 1 to 1 max  (100.00%)Rows examined : 0 avg, 0 to 0 max  (0.00%)Database      : Users         :         root@localhost  : 100.00% (3) of query, 100.00% (3) of all usersQuery abstract:SET timestamp=N; SELECT sleep(N);Query sample:SET timestamp=1403060753;select sleep(5);	 使用 percona-toolkit 的 pt-query-digest （好工具）。root@slave1 opt]# wget http://www.percona.com/downloads/percona-toolkit/LATEST/RPM/percona-toolkit-2.2.8-1.noarch.rpm[root@slave1 opt]# ls -s percona-toolkit-2.2.8-1.noarch.rpm 1652 percona-toolkit-2.2.8-1.noarch.rpm[root@slave1 opt]# yum install percona-toolkit-2.2.8-1.noarch.rpm -y[root@slave1 opt]# pt-query-digest --user=root /usr/local/mysql/logs/mysql-slow # 280ms user time, 30ms system time, 24.47M rss, 207.34M vsz# Current date: Wed Jun 18 13:49:23 2014# Hostname: slave1.hadoop.com# Files: /usr/local/mysql/logs/mysql-slow# Overall: 3 total, 1 unique, 0.14 QPS, 0.73x concurrency ________________# Time range: 2014-06-18 11:05:53 to 11:06:15# Attribute          total     min     max     avg     95%  stddev  median# ============     ======= ======= ======= ======= ======= ======= =======# Exec time            16s      5s      6s      5s      6s   369ms      5s# Lock time              0       0       0       0       0       0       0# Rows sent              3       1       1       1       1       0       1# Rows examine           0       0       0       0       0       0       0# Query size            45      15      15      15      15       0      15# Profile# Rank Query ID           Response time  Calls R/Call V/M   Item# ==== ================== ============== ===== ====== ===== ======#    1 0xF9A57DD5A41825CA 16.0007 100.0%     3 5.3336  0.03 SELECT# Query 1: 0.14 QPS, 0.73x concurrency, ID 0xF9A57DD5A41825CA at byte 548# This item is included in the report because it matches --limit.# Scores: V/M = 0.03# Time range: 2014-06-18 11:05:53 to 11:06:15# Attribute    pct   total     min     max     avg     95%  stddev  median# ============ === ======= ======= ======= ======= ======= ======= =======# Count        100       3# Exec time    100     16s      5s      6s      5s      6s   369ms      5s# Lock time      0       0       0       0       0       0       0       0# Rows sent    100       3       1       1       1       1       0       1# Rows examine   0       0       0       0       0       0       0       0# Query size   100      45      15      15      15      15       0      15# String:# Hosts        localhost# Users        root# Query_time distribution#   1us#  10us# 100us#   1ms#  10ms# 100ms#    1s  #################################################################  10s+# EXPLAIN /*!50100 PARTITIONS*/select sleep(6)/G

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