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