标签：blog http io os 使用 ar for sp div
1：查看MySQL当前版本是否支持profile
mysql> SELECT @@HAVE_PROFILING; +------------------+ | @@HAVE_PROFILING | +------------------+ | YES | +------------------+ 1 row in set (0.00 sec)
2：默认profile是关闭的，查看当前profile是否打开
mysql> SELECT @@PROFILING; +-------------+ | @@PROFILING | +-------------+ | 0 | +-------------+ 1 row in set (0.00 sec)
3：打开profile
mysql> SET @@PROFILING = 1; Query OK, 0 rows affected (0.00 sec)
4：创建环境使用profile
a.创建测试表
mysql> CREATE TABLE T2
-> AS
-> SELECT * FROM mysql.user;
Query OK, 4 rows affected (0.00 sec)
Records: 4 Duplicates: 0 Warnings: 0
b.查看当前语句的ID
mysql> show profiles;
c.查看线程每个状态和执行时间
mysql> show profile for query 25; +------------------------------+----------+ | Status | Duration | +------------------------------+----------+ | starting | 0.000050 | | checking permissions | 0.000006 | | checking permissions | 0.000005 | | Opening tables | 0.000115 | | System lock | 0.000011 | | init | 0.000095 | | creating table | 0.005914 | | After create | 0.000118 | | System lock | 0.000032 | | optimizing | 0.000008 | | statistics | 0.000015 | | preparing | 0.000012 | | executing | 0.000004 | | Sending data | 0.000161 | | Waiting for query cache lock | 0.000005 | | Sending data | 0.000676 | | end | 0.000006 | | query end | 0.000002 | | closing tables | 0.000012 | | freeing items | 0.000190 | | logging slow query | 0.000003 | | cleaning up | 0.000004 | +------------------------------+----------+ 22 rows in set (0.00 sec)
标签：blog http io os 使用 ar for sp div
原文地址：http://www.cnblogs.com/xiaoit/p/4000086.html
