pt-stalk

1、名词解释

Collect forensic data about MySQL when problems occur

在问题发生的时候采集现场数据

pt-stalk waits for a trigger condition to occur, then collects data to help diagnose problems. The tool is designed to run as a daemon with root privileges, so that you can diagnose intermittent problems that you cannot observe directly. You can also use it to execute a custom command, or to collect data on demand without waiting for the trigger to occur

 

在一定条件下触发，采集一些监控数据便于分析问题。运行该功能需要有root权限。可以作为一个实时采集的功能，也可以设置触发条件。

2、例子

[root@typhoeus79 mysql_5580]# pt-stalk --collect-tcpdump --function status --variable Threads_connected --threshold  -- --user=root --password='c0BsZjR57MgAGOk6IWZAMarVVg0' --socket=./tmp/mysql.sock
Overwriting PID file /var/run/pt-stalk.pid because its PID () is not running
2013_12_25_11_11_16 Starting /data1/guosong/bin/pt-tool/bin/pt-stalk --function=status --variable=Threads_connected --threshold= --match= --cycles= --interval= --iterations= --run-time= --sleep= --dest=/var/lib/pt-stalk --prefix= --notify-by-email= --log=/var/log/pt-stalk.log --pid=/var/run/pt-stalk.pid --plugin=
2013_12_25_11_11_53 Check results: status(Threads_connected)=, matched=yes, cycles_true=
2013_12_25_11_11_54 Check results: status(Threads_connected)=, matched=yes, cycles_true=
2013_12_25_11_11_55 Check results: status(Threads_connected)=, matched=yes, cycles_true=
2013_12_25_11_11_56 Check results: status(Threads_connected)=, matched=yes, cycles_true=
2013_12_25_11_11_57 Check results: status(Threads_connected)=, matched=yes, cycles_true=
2013_12_25_11_11_57 Collect  triggered
2013_12_25_11_11_57 Collect  PID
2013_12_25_11_12_06 Collect  done
2013_12_25_11_12_06 Sleeping  seconds after collect

采集的数据放在--dest目录下，包含如下文件：

这些数据都是原始数据，我们可以根据这些来分析当时MySQL或者主机是否有异常

http://www.orczhou.com/index.php/2012/06/mysql-troubleshooting-with-pt-stakl/