mysql SHOW PROFILE

SHOW PROFILE [type [, type] ... ]
    [FOR QUERY n]
    [LIMIT row_count [OFFSET offset]]

type: {
    ALL
  | BLOCK IO
  | CONTEXT SWITCHES
  | CPU
  | IPC
  | MEMORY
  | PAGE FAULTS
  | SOURCE
  | SWAPS
}

SHOW PROFILE 和SHOW PROFILES语句显示分析信息，这些信息指示在当前会话过程中执行的语句的资源使用情况。每个会话启用分析后，当会话结束时，其分析信息将丢失。

SHOW PROFILE 和SHOW PROFILES 已经被弃用了，未来将不使用这个。

The SHOW PROFILE and SHOW PROFILES statements are deprecated; expect them to be removed in a future MySQL release. Use the Performance Schema instead; see Section 29.19.1, “Query Profiling Using Performance Schema”.

#设置为1，开启性能分析
mysql> SET profiling = 1;
#查看配置
mysql> SELECT @@profiling;
+-------------+
| @@profiling |
+-------------+
|           0 |
+-------------+
1 row in set (0.00 sec)
#开启分析
mysql> SET profiling = 1;
Query OK, 0 rows affected (0.00 sec)

#执行任意的sql语句
mysql> DROP TABLE IF EXISTS t1;
Query OK, 0 rows affected, 1 warning (0.00 sec)

mysql> CREATE TABLE T1 (id INT);
Query OK, 0 rows affected (0.01 sec)


## 查看执行过的sql 的QUERYID，Duration持续时间
mysql> SHOW PROFILES;
+----------+----------+--------------------------+
| Query_ID | Duration | Query                    |
+----------+----------+--------------------------+
|        0 | 0.000088 | SET PROFILING = 1        |
|        1 | 0.000136 | DROP TABLE IF EXISTS t1  |
|        2 | 0.011947 | CREATE TABLE t1 (id INT) |
+----------+----------+--------------------------+
3 rows in set (0.00 sec)
#最近一个查询的 profile 信息   
mysql> SHOW PROFILE;
+----------------------+----------+
| Status               | Duration |
+----------------------+----------+
| checking permissions | 0.000040 |
| creating table       | 0.000056 |
| After create         | 0.011363 |
| query end            | 0.000375 |
| freeing items        | 0.000089 |
| logging slow query   | 0.000019 |
| cleaning up          | 0.000005 |
+----------------------+----------+
7 rows in set (0.00 sec)

mysql> SHOW PROFILE FOR QUERY 1;
+--------------------+----------+
| Status             | Duration |
+--------------------+----------+
| query end          | 0.000107 |
| freeing items      | 0.000008 |
| logging slow query | 0.000015 |
| cleaning up        | 0.000006 |
+--------------------+----------+
4 rows in set (0.00 sec)

mysql> SHOW PROFILE CPU FOR QUERY 2;
+----------------------+----------+----------+------------+
| Status               | Duration | CPU_user | CPU_system |
+----------------------+----------+----------+------------+
| checking permissions | 0.000040 | 0.000038 |   0.000002 |
| creating table       | 0.000056 | 0.000028 |   0.000028 |
| After create         | 0.011363 | 0.000217 |   0.001571 |
| query end            | 0.000375 | 0.000013 |   0.000028 |
| freeing items        | 0.000089 | 0.000010 |   0.000014 |
| logging slow query   | 0.000019 | 0.000009 |   0.000010 |
| cleaning up          | 0.000005 | 0.000003 |   0.000002 |
+----------------------+----------+----------+------------+
7 rows in set (0.00 sec)

SHOW PROFILES 显示最近发送到服务器的语句的列表。列表的大小由profiling_history_size会话变量控制，该变量的默认值为15。最大值为100。将该值设置为0具有禁用分析的实际效果。

分析信息也可从INFORMATION_SCHEMA PROFILING表中获得。请参见第28.3.24节“INFORMATION_SCHEMA PROFILING表”。例如，以下查询是等效的：

SHOW PROFILE FOR QUERY 2;

SELECT STATE, FORMAT(DURATION, 6) AS DURATION
FROM INFORMATION_SCHEMA.PROFILING
WHERE QUERY_ID = 2 ORDER BY SEQ;