mysql老是自动停止，导致wordpress连接数据库失败，于是我去求助伟大的推神: 我的digtalocean上VPS上的mysql数据库老是自动停掉，这是怎么回事啊？我用的操作系统是 Ubuntu 12.10 , /var/log/ 底下 的mysqld.log mysql.err mysql.log 都是空的，不知道发生什么事了.过了一会儿，大神出现了：
@zuola 看dmesg有无系统级错误，我遇到过数据库分配的内存过多被系统给杀死了
— 蜗牛(sn)…… (@ZealYi) 2014年5月1日
我输入dmesg，果然发现mysql respawning too fast,的字样了
[422425.267037] send sigkill to 5605 (mysqld), adj 0, size 16693
[422425.348455] init: mysql main process (5605) killed by KILL signal
[422425.356550] init: mysql main process ended, respawning
[422425.811580] init: mysql main process (10805) terminated with status 1
[422425.811629] init: mysql main process ended, respawning
[422426.728623] init: mysql post-start process (10806) terminated with status 1
[422426.779367] init: mysql main process (10840) terminated with status 1
[422426.779402] init: mysql respawning too fast, stopped
[452934.665293] select 1 (init), adj 0, size 285, to kill
[452934.665301] select 379 (rsyslogd), adj 0, size 695, to kill
[452934.665304] select 1006 (apache2), adj 0, size 1975, to kill
[452934.665306] select 18429 (apache2), adj 0, size 10799, to kill
[452934.665309] select 11546 (mysqld), adj 0, size 16458, to kill
[452934.665311] send sigkill to 11546 (mysqld), adj 0, size 16458
[452934.761547] init: mysql main process (11546) killed by KILL signal
[452934.768425] init: mysql main process ended, respawning
[452935.139794] init: mysql main process (17045) terminated with status 1
[452935.139829] init: mysql main process ended, respawning
[452935.157952] init: mysql post-start process (17046) terminated with status 1
[452935.207468] init: mysql main process (17072) terminated with status 1
[452935.207501] init: mysql respawning too fast, stopped
上网搜索 mysql respawning too fast，找到
http://askubuntu.com/questions/127264/cant-start-mysql-mysql-respawning-too-fast-stopped
解决办法是
dpkg-reconfigure mysql-server-5.5
不要先删除低版本的mysql
apt-get remove mysql-server-5.5
再安装
apt-get install mysql-server-5.5
然后才能使用
dpkg-reconfigure mysql-server-5.5
先试试看，好像mysql还会不会自动停止掉了。
造成mysql自动停止的原因似乎是字符编码问题,不使用上面的方法，可以直接修改 /etc/mysql/my.cnf 文件
要修改 /etc/mysql/my.cnf 里的 [client]和[myslqd] 中的内容，添加指定字体编码
[client]
default-character-set=utf8
[myslqd]
character_set_server=utf8
collation_server = utf8_general_ci
character_set_server=utf8
collation_server = utf8_general_ci
再reboot服务器，然后dmesg,果然没有 mysql respawning too fast。半天过去了，wordpress也没有出现无法链接数据库了。
参考链接：
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