MySQL 性能监控

MySQL 性能监控

show profile查询工具

使用show profile查询剖析工具，可以指定具体的type

速查表

示例

// 执行sql
select * from drafts;
// 查询结果
259	0.00108325	SHOW STATUS
260	0.0008205	SHOW STATUS
261	0.000804	SHOW STATUS
262	0.000903	SELECT QUERY_ID, SUM(DURATION) AS SUM_DURATION FROM INFORMATION_SCHEMA.PROFILING GROUP BY QUERY_ID
263	0.00083525	SELECT STATE AS `Status`, ROUND(SUM(DURATION),7) AS `Duration`, CONCAT(ROUND(SUM(DURATION)/0.001828*100,3), '') AS `Percentage` FROM INFORMATION_SCHEMA.PROFILING WHERE QUERY_ID=248 GROUP BY SEQ, STATE ORDER BY SEQ
264	0.00012	SET PROFILING = 1
265	0.00110675	SHOW STATUS
266	0.000854	SHOW STATUS
267	0.00183225	select * from drafts
268	0.0007695	SHOW STATUS
269	0.0008965	SELECT QUERY_ID, SUM(DURATION) AS SUM_DURATION FROM INFORMATION_SCHEMA.PROFILING GROUP BY QUERY_ID
270	0.00086	SELECT STATE AS `Status`, ROUND(SUM(DURATION),7) AS `Duration`, CONCAT(ROUND(SUM(DURATION)/0.000789*100,3), '') AS `Percentage` FROM INFORMATION_SCHEMA.PROFILING WHERE QUERY_ID=255 GROUP BY SEQ, STATE ORDER BY SEQ
271	0.00015925	SET PROFILING = 1
272	0.00108775	SHOW STATUS
273	0.00092375	SHOW STATUS
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18

// 执行sql
show profile all for query 267;

// 执行结果
starting	0.000044	0.000027	0.000015	0	0	0	0	0	0	0	0	0			
checking permissions	0.000007	0.000006	0.000000	0	0	0	0	0	0	0	0	0	check_access	sql_authorization.cc	809
Opening tables	0.000014	0.000009	0.000006	0	0	0	0	0	0	0	0	0	open_tables	sql_base.cc	5815
init	0.000020	0.000010	0.000010	0	0	0	0	0	0	0	0	0	handle_query	sql_select.cc	128
System lock	0.000007	0.000006	0.000000	0	0	0	0	0	0	0	0	0	mysql_lock_tables	lock.cc	330
optimizing	0.000004	0.000004	0.000000	0	0	0	0	0	0	0	0	0	optimize	sql_optimizer.cc	158
statistics	0.000009	0.000004	0.000005	0	0	0	0	0	0	0	0	0	optimize	sql_optimizer.cc	374
preparing	0.000007	0.000006	0.000000	0	0	0	0	0	0	0	0	0	optimize	sql_optimizer.cc	482
executing	0.000003	0.000003	0.000000	0	0	0	0	0	0	0	0	0	exec	sql_executor.cc	126
Sending data	0.001676	0.000243	0.000112	1	0	0	0	0	0	0	0	0	exec	sql_executor.cc	202
end	0.000010	0.000008	0.000000	0	0	0	0	0	0	0	0	0	handle_query	sql_select.cc	206
query end	0.000008	0.000002	0.000005	0	0	0	0	0	0	0	0	0	mysql_execute_command	sql_parse.cc	4957
closing tables	0.000007	0.000007	0.000000	0	0	0	0	0	0	0	0	0	mysql_execute_command	sql_parse.cc	5016
freeing items	0.000009	0.000004	0.000006	0	0	0	0	0	0	0	0	0	mysql_parse	sql_parse.cc	5635
cleaning up	0.000009	0.000009	0.000000	0	0	0	0	0	0	0	0	0	dispatch_command	sql_parse.cc	1931
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19

performance schema监控MySQL

​ MySQL的performance schema 用于监控MySQL server在一个较低级别的运行过程中的资源消耗、资源等待等情况。

入门

在mysql的5.7版本中，性能模式是默认开启的，如果想要显式的关闭的话需要修改配置文件，不能直接进行修改，会报错Variable ‘performance_schema’ is a read only variable。

--查看performance_schema的属性
mysql> SHOW VARIABLES LIKE 'performance_schema';
+--------------------+-------+
| Variable_name      | Value |
+--------------------+-------+
| performance_schema | ON    |
+--------------------+-------+
1 row in set (0.01 sec)

--在配置文件中修改performance_schema的属性值，on表示开启，off表示关闭
[mysqld]
performance_schema=ON

--切换数据库
use performance_schema;

--查看当前数据库下的所有表,会看到有很多表存储着相关的信息
show tables;

--可以通过show create table tablename来查看创建表的时候的表结构
mysql> show create table setup_consumers;
+-----------------+---------------------------------
| Table           | Create Table                    
+-----------------+---------------------------------
| setup_consumers | CREATE TABLE `setup_consumers` (
  `NAME` varchar(64) NOT NULL,                      
  `ENABLED` enum('YES','NO') NOT NULL               
) ENGINE=PERFORMANCE_SCHEMA DEFAULT CHARSET=utf8 |  
+-----------------+---------------------------------
1 row in set (0.00 sec)         
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30

速查SQL

--1、哪类的SQL执行最多？
SELECT DIGEST_TEXT,COUNT_STAR,FIRST_SEEN,LAST_SEEN FROM events_statements_summary_by_digest ORDER BY COUNT_STAR DESC
--2、哪类SQL的平均响应时间最多？
SELECT DIGEST_TEXT,AVG_TIMER_WAIT FROM events_statements_summary_by_digest ORDER BY COUNT_STAR DESC
--3、哪类SQL排序记录数最多？
SELECT DIGEST_TEXT,SUM_SORT_ROWS FROM events_statements_summary_by_digest ORDER BY COUNT_STAR DESC
--4、哪类SQL扫描记录数最多？
SELECT DIGEST_TEXT,SUM_ROWS_EXAMINED FROM events_statements_summary_by_digest ORDER BY COUNT_STAR DESC
--5、哪类SQL使用临时表最多？
SELECT DIGEST_TEXT,SUM_CREATED_TMP_TABLES,SUM_CREATED_TMP_DISK_TABLES FROM events_statements_summary_by_digest ORDER BY COUNT_STAR DESC
--6、哪类SQL返回结果集最多？
SELECT DIGEST_TEXT,SUM_ROWS_SENT FROM events_statements_summary_by_digest ORDER BY COUNT_STAR DESC
--7、哪个表物理IO最多？
SELECT file_name,event_name,SUM_NUMBER_OF_BYTES_READ,SUM_NUMBER_OF_BYTES_WRITE FROM file_summary_by_instance ORDER BY SUM_NUMBER_OF_BYTES_READ + SUM_NUMBER_OF_BYTES_WRITE DESC
--8、哪个表逻辑IO最多？
SELECT object_name,COUNT_READ,COUNT_WRITE,COUNT_FETCH,SUM_TIMER_WAIT FROM table_io_waits_summary_by_table ORDER BY sum_timer_wait DESC
--9、哪个索引访问最多？
SELECT OBJECT_NAME,INDEX_NAME,COUNT_FETCH,COUNT_INSERT,COUNT_UPDATE,COUNT_DELETE FROM table_io_waits_summary_by_index_usage ORDER BY SUM_TIMER_WAIT DESC
--10、哪个索引从来没有用过？
SELECT OBJECT_SCHEMA,OBJECT_NAME,INDEX_NAME FROM table_io_waits_summary_by_index_usage WHERE INDEX_NAME IS NOT NULL AND COUNT_STAR = 0 AND OBJECT_SCHEMA <> 'mysql' ORDER BY OBJECT_SCHEMA,OBJECT_NAME;
--11、哪个等待事件消耗时间最多？
SELECT EVENT_NAME,COUNT_STAR,SUM_TIMER_WAIT,AVG_TIMER_WAIT FROM events_waits_summary_global_by_event_name WHERE event_name != 'idle' ORDER BY SUM_TIMER_WAIT DESC
--12-1、剖析某条SQL的执行情况，包括statement信息，stege信息，wait信息
SELECT EVENT_ID,sql_text FROM events_statements_history WHERE sql_text LIKE '%count(*)%';
--12-2、查看每个阶段的时间消耗
SELECT event_id,EVENT_NAME,SOURCE,TIMER_END - TIMER_START FROM events_stages_history_long WHERE NESTING_EVENT_ID = 1553;
--12-3、查看每个阶段的锁等待情况
SELECT event_id,event_name,source,timer_wait,object_name,index_name,operation,nesting_event_id FROM events_waits_history_longWHERE nesting_event_id = 1553;
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28

show processlist

使用show processlist查看连接的线程个数，来观察是否有大量线程处于不正常的状态或者其他不正常的特征

属性说明

属性commond状态说明