转:解决mysql锁表终极方法 很多时候!一不小心就锁表!这里讲解决锁表终极方法! 案例一 mysqlshow?processlist; 参看sql语句 一般少的话 mysqlkill?thread_id; 就可以解决了 kill掉第一个锁表的进程,?依然没有改善.?既然不改善,?咱们就想办法将所有锁表的进
转:解决mysql锁表终极方法很多时候!一不小心就锁表!这里讲解决锁表终极方法!
案例一
mysql>show?processlist;
参看sql语句
一般少的话
mysql>kill?thread_id;
就可以解决了
kill掉第一个锁表的进程,?依然没有改善.?既然不改善,?咱们就想办法将所有锁表的进程kill掉吧,?简单的脚本如下.
#!/bin/bash
mysql?-u?root?-e?"show?processlist"?|?grep?-i?"Locked"?>>?locked_log.txt
for?line?in?`cat?locked_log.txt?|?awk?'{print?$1}'`
do?
echo?"kill?$line;"?>>?kill_thread_id.sql
done
现在kill_thread_id.sql的内容像这个样子
kill?66402982;
kill?66402983;
kill?66402986;
kill?66402991;
.....
好了,?我们在mysql的shell中执行,?就可以把所有锁表的进程杀死了.
mysql>source?kill_thread_id.sql
当然了,?也可以一行搞定
for?id?in?`mysqladmin?processlist?|?grep?-i?locked?|?awk?'{print?$1}'`
do
mysqladmin?kill?${id}
done?
案例二?如果大批量的操作能够通过一系列的select语句产生,那么理论上就能对这些结果批量处理。
但是mysql并没用提供eval这样的对结果集进行分析操作的功能。所以只能现将select结果保存到临时文件中,然后再执行临时文件中的指令。
具体过程如下:mysql>?SELECT?concat('KILL?',id,';')?FROM?information_schema.processlist?WHERE?user='root';
+------------------------+
|?concat('KILL?',id,';')?
+------------------------+
|?KILL?3101;?????????????
|?KILL?2946;?????????????
+------------------------+
2?rows?IN?SET?(0.00?sec)mysql>?SELECT?concat('KILL?',id,';')?FROM?information_schema.processlist?WHERE?user='root'?INTO?OUTFILE?'/tmp/a.txt';
Query?OK,?2?rows?affected?(0.00?sec)mysql>?source?/tmp/a.txt;
Query?OK,?0?rows?affected?(0.00?sec)??
案例三?MySQL?+?PHP的模式在大并发压力下经常会导致MySQL中存在大量僵死进程,导致服务挂死。为了自动干掉这些进程,弄了个脚本,放在服务器后台通过crontab自动执行。发现这样做了以后,的确很好的缓解了这个问题。把这个脚本发出来和大家Share.?根据自己的实际需要,做了一些修改:
SHELL脚本:mysqld_kill_sleep.sh
#!/bin/sh?
mysql_pwd="root的密码"?
mysqladmin_exec="/usr/local/bin/mysqladmin"?
mysql_exec="/usr/local/bin/mysql"?
mysql_timeout_dir="/tmp"?
mysql_timeout_log="$mysql_timeout_dir/mysql_timeout.log"?
mysql_kill_timeout_sh="$mysql_timeout_dir/mysql_kill_timeout.sh"?
mysql_kill_timeout_log="$mysql_timeout_dir/mysql_kill_timeout.log"?
$mysqladmin_exec?-uroot?-p"$mysql_pwd"?processlist?|?awk?'{?print?$12?,?$2?,$4}'?|?grep?-v?Time?|?grep?-v?'|'?|?sort?-rn?>?$mysql_timeout_log?
awk?'{if($1>30?&&?$3!="root")?print?"'""$mysql_exec""'?-e?"?"\""?"kill",$2?"\""?"?-uroot?"?"-p""\"""'""$mysql_pwd""'""\""?";"?}'?$mysql_timeout_log?>?$mysql_kill_timeout_sh?
echo?"check?start?...."?>>?$mysql_kill_timeout_log?
echo?`date`?>>?$mysql_kill_timeout_log?
cat?$mysql_kill_timeout_sh把这个写到mysqld_kill_sleep.sh。然后chmod?0?mysqld_kill_sleep.sh,chmod?u+rx?mysqld_kill_sleep.sh,然后用root账户到cron里面运行即可,时间自己调整。?
执行之后显示:?
www#?./mysqld_kill_sleep.sh?
/usr/local/bin/mysql?-e?"kill?27549"?-uroot?-p"mysql?root的密码";?
/usr/local/bin/mysql?-e?"kill?27750"?-uroot?-p"mysql?root的密码";?
/usr/local/bin/mysql?-e?"kill?27840"?-uroot?-p"mysql?root的密码";?
/usr/local/bin/mysql?-e?"kill?27867"?-uroot?-p"mysql?root的密码";?
/usr/local/bin/mysql?-e?"kill?27899"?-uroot?-p"mysql?root的密码";?
/usr/local/bin/mysql?-e?"kill?27901"?-uroot?-p"mysql?root的密码";?
/usr/local/bin/mysql?-e?"kill?27758"?-uroot?-p"mysql?root的密码";?
/usr/local/bin/mysql?-e?"kill?27875"?-uroot?-p"mysql?root的密码";?
/usr/local/bin/mysql?-e?"kill?27697"?-uroot?-p"mysql?root的密码";?
/usr/local/bin/mysql?-e?"kill?27888"?-uroot?-p"mysql?root的密码";?
/usr/local/bin/mysql?-e?"kill?27861"?-uroot?-p"mysql?root的密码";
如果确认没有问题了,把最后的cat修改为sh即可。
本人改写了下上面的脚本:
#!/bin/bash?
mysql_pwd="密码"?
mysql_exec="/usr/local/mysql/bin/mysql"?
mysql_timeout_dir="/tmp"?
mysql_kill_timeout_sh="$mysql_timeout_dir/mysql_kill_timeout.sh"?
mysql_kill_timeout_log="$mysql_timeout_dir/mysql_kill_timeout.log"?
$mysql_exec?-uroot?-p$mysql_pwd?-e?"show?processlist"?|?grep?-i?"Locked"?>>?$mysql_kill_timeout_log?
chmod?777?$mysql_kill_timeout_log?
for?line?in?`$mysql_kill_timeout_log??|?awk?'{print?$1}'`?
do?
echo?"$mysql_exec?-uroot?-p$mysql_pwd?-e?\"kill?$line\""?>>?$mysql_kill_timeout_sh?
done?
chmod?777?$mysql_kill_timeout_sh?
cat?$mysql_kill_timeout_sh?是不是很方便呢!
最后贴个我在用的脚本
?
1 2 3 4 5 |
#!/bin/bash
mysql -uroot -pxxxxx -e? "show processlist" ?| grep ?-i? "Lock" ?| awk ?'{print $1}' ?>sqlid.sql
sed ?-i? 's/^/kill\ /g' ?
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 |
kill 2;
kill 1088;
kill 1265;
kill 1274;
kill 1287;
kill 1288;
kill 1289;
kill 1290;
kill 1291;
kill 1295;
kill 1296;
kill 1298;
kill 1299;
kill 1302;
kill 1304;
kill 1305;
kill 1309;
|
?
文章转自:http://hi.baidu.com/hunter6536/item/844223c05f0a9934449416ad

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