今天处理一个case: 数据库异常,连接数突增。
想着分析一下慢日志,可是一看慢日志都好几G了,而且是短日志格式,找到那个时间点相对比较难。于是写了一个脚本从慢日志按时间提取点日志。脚本:
https://github.com/wubx/mysql-binlog-statistic/blob/master/bin/cutlogbytime
使用方法:
代码如下:
cutlogbytime
#用于从慢日志用截取一个时间段的日志方便分析
./cutlogbytime /path/slowlogfile starttime endtime > dstfile.log
时间需要写时戳
mysql> select unix_timestamp('2013-04-05'); +------------------------------+ | unix_timestamp('2013-04-05') | +------------------------------+ | 1365091200 | +------------------------------+ 1 row in set (0.00 sec) mysql> select unix_timestamp('2013-04-06'); +------------------------------+ | unix_timestamp('2013-04-06') | +------------------------------+ | 1365177600 | +------------------------------+ 1 row in set (0.00 sec)
./cutlogbytime /path/slowlogfile 1365091200 1365177600 > 20130405_slow.log
这样得到一天的日志文件就小一点的也容易分析了。而且可以根据天的文件,在取一天的某个时间点的日志。

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