mysql系统监控调优工具tuning-primer.sh

简介：

该脚本使用 "SHOW STATUS LIKE..." 和 "SHOW VARIABLES LIKE..." 命令获得MySQL相关变量和运行状态。然后根据推荐的调优参数对当前的MySQL数据库进行测试。最后根据不同颜色的标识来提醒用户需要注意的各个参数设置。该版本兼容 MySQL 3.23 和更高版本（包含 5.1）

当前版本会处理如下这些推荐的参数：

 Slow Query Log （慢查询日志）
 Max Connections （最大连接数）
 Worker Threads （工作线程）
 Key Buffer （Key 缓冲）
 Query Cache （查询缓存）
 Sort Buffer （排序缓存）
 Joins （连接）
 Temp Tables （临时表）
 Table (Open & Definition) Cache （表缓存）
 Table Locking （表锁定）
 Table Scans (read_buffer) （表扫描，读缓冲）
 Innodb Status （Innodb 状态）

下载使用：
http://www.day32.com/MySQL/tuning-primer.sh
tuning-primer.sh 有如下运行参数:
Usage: ./tuning-primer.sh [ mode ]

all 运行所有检测(默认值)
prompt 提示
mem, memory 运行有关内存使用方面的检测
disk, file 运行有关I/O性能和文件处理限制方面的检测
innodb 运行InnoDB检测
misc 其它

脚本支持my.cnf文件，可以把user, password, host, socket等连接参数放在~/.my.cnf文件里，如果使用了自定义的socket文件，请修改tuning-primer.sh文件中关于socket文件位置的变量。

运行 tuning-primer.sh

SLOW QUERIES

慢查询检查

SLOW QUERIES

The slow query log is enabled.

说明我已经启用了慢查询记录功能。也就是参数
slow_query_log = 1

Current long_query_time = 5.000000 sec.

慢查询的阀值时间。也就是参数
long_query_time = 5

You have 17 out of 638844 that take longer than 5.000000 sec. to complete

说明慢查询日志中记录了17条查询时间超过5秒的语句。
slow_query_log_file=/data/ats_db/mysql-slow.log

设置慢查询日志路径。使用

mysqldumpslow命令查询慢日志

Your long_query_time seems to be fine

慢查询阀值时间设置得在推荐的范围内

BINARY UPDATE LOG

更新二进制日志文件

The binary update log is enabled

这项说明启用了bin-log日志功能。参数
log-bin = /data/ats_db/mysql-bin

Binlog sync is not enabled, you could loose binlog records during a server crash

没有启用 sync_binlog 选项。也即是将二进制日志实时写入到磁盘通过 sync_binlog=1来指定

WORKER THREADS

工作线程

Current thread_cache_size = 8

当前线程缓存大小。
thread_concurrency = 8

Current threads_cached = 7

Show status like 'threads_cached'

Current threads_per_sec = 0

脚本先执行Show status like 'Threads_cached'查看当前的线程创建情况，然后sleep 1后在执行相同的命令，最终后者减去前者的数就是每秒线程创建数。

Historic threads_per_sec = 0

该值是使用Threads_cached /uptime获得的。

Your thread_cache_size is fine

MAX CONNECTIONS

最大连接数

Current max_connections = 1024

当前配置文件中设置的并发连接数

Current threads_connected = 2

当前线程连接诶数。
show status like 'Threads_connected'

Historic max_used_connections = 4

show status like 'Max_used_connections';

The number of used connections is 0% of the configured maximum.

这个值使用 Max_used_connections*100/ max_connections得出。

You are using less than 10% of your configured max_connections.

Lowering max_connections could help to avoid an over-allocation of memory

See "MEMORY USAGE" section to make sure you are not over-allocating

Max_used_connections的值不足max_connections值的10%。设置合适的max_connections值有助于节省内存。

MEMORY USAGE

内存使用

Max Memory Ever Allocated : 841 M

Max Memory Ever Allocated = max_memory

Configured Max Per-thread Buffers : 28.40 G

Configured Max Per-thread Buffers = per_thread_buffers

Configured Max Global Buffers : 586 M

Configured Max Global Buffers = per_thread_max_buffers

Configured Max Memory Limit : 28.97 G

Configured Max Memory Limit = total_memory
这一项很重要，他是将各个缓存的大小累加，然后同max_connections相乘，从而得出当达到max_connections后需要分配的内存有多少。我这里由于max_connections写得很大，造成了最大内存限制超过了真实内存很多，所以建议不要随意增大max_connections的值。减小 max_connections的值，最终保证最大内存限制在真实内存的90%以下。

Physical Memory : 7.79 G

实际物理内存

Max memory limit exceeds 90% of physical memory

per_thread_buffers
(read_buffer_size+read_rnd_buffer_size +sort_buffer_size+thread_stack+
join_buffer_size+binlog_cache_size)*max_connections

per_thread_max_buffers
(read_buffer_size+read_rnd_buffer_size +sort_buffer_size+thread_stack
+join_buffer_size+binlog_cache_size)*max_used_connections

global_buffers
innodb_buffer_pool_size+innodb_additional_mem_pool_size+innodb_log_buffer_size+
key_buffer_size+query_cache_size

max_memory=global_buffers+per_thread_max_buffers

total_memory=global_buffers+per_thread_buffers

KEY BUFFER

Key 缓冲

Current MyISAM index space = 222 K

当前数据库MyISAM表中索引占用磁盘空间

Current key_buffer_size = 512 M

MySQL配置文件中key_buffer_size 设置的大小

Key cache miss rate is 1 : 3316

Key_read_requests/ Key_reads 这里说明3316次读取请求中有1次丢失(也就是说1次读取磁盘)

Key buffer free ratio = 81 %

key_blocks_unused * key_cache_block_size / key_buffer_size * 100

Your key_buffer_size seems to be fine

QUERY CACHE

Query 缓存

Query cache is enabled

该项说明 我们指定了query_cache_size 的值。如果query_cache_size=0的话这里给出的提示是：
Query cache is supported but not enabled
Perhaps you should set the query_cache_size

Current query_cache_size = 64 M

当前系统query_cache_size 值大小 [F]

Current query_cache_used = 1 M

query_cache_used =query_cache_size-qcache_free_memory

Current query_cache_limit = 128 M

变量 query_cache_limit 大小

Current Query cache Memory fill ratio = 1.79 %

query_cache_used/query_cache_size *100%

Current query_cache_min_res_unit = 4 K

show variables like 'query_cache_min_res_unit';

Your query_cache_size seems to be too high.
Perhaps you can use these resources elsewhere

这项给出的结论是query_cache_size的值设置的有些过高。其比对标准是 "Query cache Memory fill ratio"的值如果小于<25%就会给出这个提示。可以将这些资源应用到其他的地方

MySQL won't cache query results that are larger than query_cache_limit in size

MySQL不会将大于query_cache_limit的查询结果进行缓存

show status like 'Qcache%';

Qcache_free_blocks 10
Qcache_free_memory 65891984
Qcache_hits 14437
Qcache_inserts 707
Qcache_lowmem_prunes 0
Qcache_not_cached 216
Qcache_queries_in_cache 540
Qcache_total_blocks 1191

SORT OPERATIONS

SORT 选项

Current sort_buffer_size = 6 M

show variables like 'sort_buffer%';

Current read_rnd_buffer_size = 16 M

show variables like 'read_rnd_buffer_size%';

Sort buffer seems to be fine

JOINS

JOINS

Current join_buffer_size = 132.00 K

show variables like 'join_buffer_size%';

join_buffer_size= join_buffer_size+4kb

You have had 6 queries where a join could not use an index properly

这里的6是通过 show status like 'Select_full_join'; 获得的

You should enable "log-queries-not-using-indexes"
Then look for non indexed joins in the slow query log.
If you are unable to optimize your queries you may want to increase your
join_buffer_size to accommodate larger joins in one pass.

Note! This script will still suggest raising the join_buffer_size when
ANY joins not using indexes are found.

你需要启用 "log-queries-not-using-indexes" 然后在慢查询日志中看是否有取消索引的joins语句。如果不优化查询语句的话，则需要增大join_buffer_size。

OPEN FILES LIMIT

文件打开数限制

Current open_files_limit = 1234 files

show variables like 'open_files_limit%';

The open_files_limit should typically be set to at least 2x-3x

that of table_cache if you have heavy MyISAM usage.

如果系统中有很多的MyISAM类型的表，则建议将open_files_limit 设置为2X~3X的table_open_cache
show status like 'Open_files';

open_files_ratio= open_files*100/open_files_limit
如果open_files_ratio 超过75% 则需要加大open_files_limit

Your open_files_limit value seems to be fine

TABLE CACHE

TABLE 缓存

Current table_open_cache = 512 tables

show variables like 'table_open_cache';

Current table_definition_cache = 256 tables

show variables like ' table_definition_cache ';

You have a total of 368 tables

SELECT

COUNT(*) FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_TYPE='BASE TABLE'

You have 371 open tables.

show status like 'Open_tables';

The table_cache value seems to be fine

Open_tables /table_open_cache*100% < 95%

You should probably increase your table_definition_cache value.

table_cache_hit_rate =open_tables*100/opened_tables

TEMP TABLES

临时表

Current max_heap_table_size = 16 M

show variables like 'max_heap_table_size';

Current tmp_table_size = 16 M

show variables like 'tmp_table_size';

Of 285 temp tables, 11% were created on disk

Created_tmp_tables=285

created_tmp_disk_tables*100/
(created_tmp_tables+created_tmp_disk_tables)=11%

Created disk tmp tables ratio seems fine

TABLE SCANS

扫描表

Current read_buffer_size = 6 M

show variables like 'read_buffer_size';

Current table scan ratio = 9 : 1

read_rnd_next =show global status like 'Handler_read_rnd_next';
com_select= show global status like 'Com_select';
full_table_scans=read_rnd_next/com_select
Current table scan ratio = full_table_scans : 1"
如果表扫描率超过4000，说明进行了太多表扫描，很有可能索引没有建好，增加read_buffer_size值会有一些好处，但最好不要超过8MB。

read_buffer_size seems to be fine

TABLE LOCKING

TABLE LOCKING

Current Lock Wait ratio = 0 : 5617

show global status like

'Table_locks_waited';
show global status like

'Questions';
如果 Table_locks_waited=0
Current Lock Wait ratio = 0: Questions

Your table locking seems to be fine