之前写过一篇文章MySQL如何获取binlog的开始时间和结束时间,文章里面介绍了如何获取MySQL数据库二进制日志(binlog)的开始时间与结束时间的一些方法。实际应用当中,我们可能还会遇到效率/性能方面的问题。最近对这个问题做了一些研究,这里就介绍一下如何快速获取MySQL二进制日志(binlog)的开始时间和结束时间。
我们下来看看当MySQL二进制日志(binlog)的Size很大的时候,获取二进制日志(binlog)的开始时间和结束时间,如下测试所示
$ du -sh mysql_binlog.000105
1.1G mysql_binlog.000105
$ time mysqlbinlog mysql_binlog.000105 |grep "Start: binlog" | awk -F "server id" '{print $1}'
#240425 9:20:26
real 0m34.136s
user 0m25.941s
sys 0m11.985s
从上面实验可以看出,在MySQL二进制日志(binlog)变大的情况下,这种方法需要34秒,非常低效和耗时,那么我们怎么提升性能呢?我们改写一下脚本,如下所示
$ time mysqlbinlog mysql_binlog.000105 | head -10 | grep "Start: binlog" | awk -F "server id" '{print $1}'
#240425 9:20:26
real 0m0.010s
user 0m0.006s
sys 0m0.005s
如上所示,这样改进脚本后,性能效率已经提升到0.01秒,已经相当的高效了。那么获取结束时间能否也可以这样提升呢?很遗憾的是由于MySQL二进制日志(binlog)的结束时间/滚动时间(Rotate Time)位于文件的末尾,由于管道的一些基本特性,获取MySQL二进制日志(binlog)的结束时间无法通过上面方法来优化,这里不打算介绍Linux管道相关概念,所以我们只需知道这么一个事实。
如果你对Linux管道的一些原理不是很清楚,那么就用实验测试验证一下,如下所示:
$ time mysqlbinlog mysql_binlog.000105 |grep Rotate | awk -F "server id" '{print $1}'
#240426 11:11:37
real 0m34.223s
user 0m27.202s
sys 0m11.551s
$ time mysqlbinlog mysql_binlog.000105 | tail -10 | grep Rotate | awk -F "server id" '{print $1}'
#240426 11:11:37
real 0m33.917s
user 0m25.528s
sys 0m11.395s
那么怎么来优化获取MySQL二进制日志(binlog)的结束时间呢?经过一番观察与实验,我发现一个MySQL二进制日志(binlog)的结束时间,就是下一个二进制日志(binlog)的开始时间。如下实验所示
[mysql@dbtest04 bin_logs]$ ls -lrt
total 28
-rw-r----- 1 mysql mysql 207 May 9 15:25 mysql_binlog.000055
-rw-r----- 1 mysql mysql 207 May 9 15:27 mysql_binlog.000056
-rw-r----- 1 mysql mysql 207 May 10 11:02 mysql_binlog.000057
-rw-r----- 1 mysql mysql 207 May 10 11:34 mysql_binlog.000058
-rw-r----- 1 mysql mysql 207 May 10 11:38 mysql_binlog.000059
-rw-r----- 1 mysql mysql 157 May 10 11:38 mysql_binlog.000060
-rw-r----- 1 mysql mysql 246 May 10 11:38 mysql_binlog.index
[mysql@dbtest04 bin_logs]$ mysqlbinlog mysql_binlog.000055 | head -10 | grep "Start: binlog" | awk -F "server id" '{print $1}'
#240509 14:48:10
[mysql@dbtest04 bin_logs]$ mysqlbinlog mysql_binlog.000055 |grep Rotate | awk -F "server id" '{print $1}'
#240509 15:25:57
[mysql@dbtest04 bin_logs]$ mysqlbinlog mysql_binlog.000056 | head -10 | grep "Start: binlog" | awk -F "server id" '{print $1}'
#240509 15:25:57
[mysql@dbtest04 bin_logs]$ mysqlbinlog mysql_binlog.000056 |grep Rotate | awk -F "server id" '{print $1}'
#240509 15:27:37
[mysql@dbtest04 bin_logs]$ mysqlbinlog mysql_binlog.000057 | head -10 | grep "Start: binlog" | awk -F "server id" '{print $1}'
#240509 15:27:37
[mysql@dbtest04 bin_logs]$ mysqlbinlog mysql_binlog.000057 |grep Rotate | awk -F "server id" '{print $1}'
#240510 11:02:00
[mysql@dbtest04 bin_logs]$
如果全部符合这个规律的话,那么我们直接用下一个binlog的开始时间作为上一个binlog的结束时间即可,于是我写了一个脚本find_binlog_start_end_time.sh:
#!/bin/bash
#########################################################################################
# #
# This script is used for get the binlog start time and end time #
# #
#########################################################################################
# #
# ScriptName : find_binlog_start_end_time.sh #
# Author : Kerry #
# CreateDate : 2024-05-10 #
# Email : kerry2008code@qq.com #
#***************************************************************************************#
# 参数配置 #
#---------------------------------------------------------------------------------------#
# 脚本参数 binlog文件存放的路径 #
#---------------------------------------------------------------------------------------#
# MYSQLBINLOG mysqlbinlog的位置,以防没有设置环境变量 #
# BINLOG_BASENAME binlog的前缀名 #
#---------------------------------------------------------------------------------------#
# 注意事项: #
# 1:如果维护的MySQL数据库都规范化安装、配置的化,下面很多参数都不需要修改 #
#***************************************************************************************#
# Version Modified Date Description #
#***************************************************************************************#
# V.1.0 2024-05-10 创建此脚本 #
#########################################################################################
# mysqlbinlog的路径,一般无需设置,以防没有设置环境变量时
MYSQLBINLOG="/opt/mysql/mysql8.0/bin/mysqlbinlog"
BINLOG_BASENAME="mysql_binlog"
if [ $# = 0 ]
then
echo "find_binlog_start_end_time.sh Usage:"
echo "for eg: find_binlog_start_end_time.sh /data/mysql/binlogs"
exit
fi
BINLOG_FILE_PATH=$1
if [ ! -d $BINLOG_FILE_PATH ];then
echo "the folder $BINLOG_FILE_PATH does not exist, please check it!"
exit 1
fi
index=1
start_time=""
end_time=""
last_binlog_name=""
BINLOG_FILE_NUM=`ls -lrt $BINLOG_FILE_PATH | grep $BINLOG_BASENAME |grep -v $BINLOG_BASENAME.index | wc -l`
if [ $BINLOG_FILE_NUM -lt 1 ];then
echo "pelase check the binlog or the parameter of this script"
exit 1;
fi
cd $BINLOG_FILE_PATH
for binlog_file in `ls -rt | grep $BINLOG_BASENAME |grep -v $BINLOG_BASENAME.index`;
do
if [ $index -eq 1 ];then
start_time=`$MYSQLBINLOG $binlog_file | head -10 | grep "Start: binlog" | awk -F "server id" '{print $1}'`
last_binlog_name=$binlog_file
else
end_time=`$MYSQLBINLOG $binlog_file | head -10 | grep "Start: binlog" | awk -F "server id" '{print $1}'`
echo "file name:$last_binlog_name" , "start time:$start_time", "end time:$end_time"
if [ $index -eq $BINLOG_FILE_NUM ];then
last_end_time=`$MYSQLBINLOG $binlog_file |tail -10 | egrep "Rotate|Stop" | awk -F "server id" '{print $1}'`
echo "file name:$binlog_file" , "start time:$end_time", "end time:$last_end_time"
else
start_time=$end_time
last_binlog_name=$binlog_file
fi
fi
let index++
done
如下测试所示
[mysql@dbtest04 kerry]$ sh find_binlog_start_end_time.sh /data/mysql/bin_logs/
file name:mysql_binlog.000055 , start time:#240509 14:48:10 , end time:#240509 15:25:57
file name:mysql_binlog.000056 , start time:#240509 15:25:57 , end time:#240509 15:27:37
file name:mysql_binlog.000057 , start time:#240509 15:27:37 , end time:#240510 11:02:00
file name:mysql_binlog.000058 , start time:#240510 11:02:00 , end time:#240510 11:34:01
file name:mysql_binlog.000059 , start time:#240510 11:34:01 , end time:#240510 11:38:24
file name:mysql_binlog.000060 , start time:#240510 11:38:24 , end time:#240510 16:45:34
file name:mysql_binlog.000061 , start time:#240510 16:45:34 , end time:
另外,还有一种比较高效的方法是解析二进制日志的头部信息(此篇文章统统指binlog v 4),因为binlog的头部由固定的4个字节组成,而头部信息的FORMAT_DESCRIPTION_EVENT部分包含了binlog的开始时间,我在搜索/学习相关资料时,结果发现有人已经总结过这方面的知识内容,而且有Python脚本或shell脚本,这里就不重复造轮子了,Python脚本来自MySQL 查询binlog生成时间[2],我们来看看实验结果,如下所示
$ python3 check_bintime.py /data/mysql/bin_logs/mysql_binlog.index
{'file_name': 'mysql_binlog.000055', 'binlog_size': '207.0 B', 'start_time': '2024-05-09 14:48:10', 'end_time': '2024-05-09 15:25:57'}
{'file_name': 'mysql_binlog.000056', 'binlog_size': '207.0 B', 'start_time': '2024-05-09 15:25:57', 'end_time': '2024-05-09 15:27:37'}
{'file_name': 'mysql_binlog.000057', 'binlog_size': '207.0 B', 'start_time': '2024-05-09 15:27:37', 'end_time': '2024-05-10 11:02:00'}
{'file_name': 'mysql_binlog.000058', 'binlog_size': '207.0 B', 'start_time': '2024-05-10 11:02:00', 'end_time': '2024-05-10 11:34:01'}
{'file_name': 'mysql_binlog.000059', 'binlog_size': '207.0 B', 'start_time': '2024-05-10 11:34:01', 'end_time': '2024-05-10 11:38:24'}
{'file_name': 'mysql_binlog.000060', 'binlog_size': '180.0 B', 'start_time': '2024-05-10 11:38:24', 'end_time': '2024-05-10 16:45:34'}
{'file_name': 'mysql_binlog.000061', 'binlog_size': '157.0 B', 'start_time': '2024-05-10 16:45:34', 'end_time': 'now'}
shell脚本来自一种快速取得binlog开始时间的方法[3]:
[mysql@dbtest04 kerry]$ function getBinlogStartTime()
> {
> theFile="$1"
> #取出文件头做分析
> binlogHead=`hexdump ${theFile} | head -1`
> #binlog文件校验
> binlogCrc=`echo $binlogHead | awk '{print $1$2$3}'`
> if [ "${binlogCrc}" != '000000062fe6e69' ]; then
> echo '${theFile} is damage.'
> exit 1
> fi
> #计算binlog的开始时间
> binlogBeginTimeInt=`echo $binlogHead | awk '{print $5$4}' | gawk ' { printf strtonum("0x" $0)}' `
> binlogBeginTime=`date -d "1970-01-01 UTC $binlogBeginTimeInt seconds" "+%F %T"`
> echo $binlogBeginTime
> }
[mysql@dbtest04 kerry]$ getBinlogStartTime /data/mysql/bin_logs/mysql_binlog.000055
2024-05-09 14:48:10
不过你看其脚本也会发现,解析MySQL的binlog的头部文件,比较容易获取binlog的开始时间,而获取binlog的结束时间/轮转时间就比较麻烦了。所以python脚本中获取binlog结束时间的思路跟我的思路也是一样的。
总结:
这里介绍了两种快速获取binlog的开始时间和结束时间的两种方法,这两种方法都非常高效,至于我写的脚本find_binlog_start_end_time.sh目前还比较粗糙,后面有时间再完善补充功能,提高脚本的健壮性。
参考资料
[1]
1: https://www.cnblogs.com/kerrycode/p/17377899.html
[2]
2: https://blog.csdn.net/qq_42768234/article/details/126970988
[3]
3: https://blog.csdn.net/shaochenshuo/article/details/120549377