SHOW PROCESSLIST;
SHOW OPEN TABLES WHERE In_use > 0;
#运行线程
SHOW GLOBAL STATUS LIKE 'Threads_running%';
#链接线程
SHOW GLOBAL STATUS LIKE 'Threads_connected%';
#查询数
SHOW GLOBAL STATUS LIKE 'Queries%';
SHOW GLOBAL STATUS LIKE 'Question%';
#提交数
SHOW GLOBAL STATUS LIKE 'Com_commit';
#回滚数
SHOW GLOBAL STATUS LIKE 'Com_rollback';
SHOW STATUS LIKE 'Binlog_cache%';
SHOW INNODB STATUS;
#日志功能参数查询
SHOW VARIABLES LIKE '%pro%';
SHOW PROFILES;
#开启语句执行时间日志功能
SET profiling=0;
#显示数据日志ID
SHOW PROFILES;
SHOW PROFILE ALL FOR QUERY 839810;
#查看当前MySQL容量状态
SELECT
table_schema AS 'Db Name',
ROUND( SUM( data_length + index_length ) / 1024 / 1024, 3 ) AS 'Db Size (MB)',
ROUND( SUM( data_free ) / 1024 / 1024, 3 ) AS 'Free Space (MB)'
FROM information_schema.tables
GROUP BY table_schema ;
mysql状态查看 QPS/TPS/缓存命中率查看
转载：http://blog.163.com/ji_1006/blog/static/106123412013101421530142/
运行中的mysql状态查看
对正在运行的mysql进行监控，其中一个方式就是查看mysql运行状态。
(1)QPS(每秒Query量)
QPS = Questions(or Queries) / seconds
mysql > show global status like 'Question%';
(2)TPS(每秒事务量)
TPS = (Com_commit + Com_rollback) / seconds
mysql > show global status like 'Com_commit';
mysql > show global status like 'Com_rollback';
(3)key Buffer 命中率
mysql>show global status like 'key%';
key_buffer_read_hits = (1-key_reads / key_read_requests) * 100%
key_buffer_write_hits = (1-key_writes / key_write_requests) * 100%
(4)InnoDB Buffer命中率
mysql> show status like 'innodb_buffer_pool_read%';
innodb_buffer_read_hits = (1 - innodb_buffer_pool_reads / innodb_buffer_pool_read_requests) * 100%
(5)Query Cache命中率
mysql> show status like 'Qcache%';
Query_cache_hits = (Qcahce_hits / (Qcache_hits + Qcache_inserts )) * 100%;
(6)Table Cache状态量
mysql> show global status like 'open%';
比较 open_tables 与 opend_tables 值
(7)Thread Cache 命中率
mysql> show global status like 'Thread%';
mysql> show global status like 'Connections';
Thread_cache_hits = (1 - Threads_created / connections ) * 100%
(8)锁定状态
mysql> show global status like '%lock%';
Table_locks_waited/Table_locks_immediate=0.3% 如果这个比值比较大的话，说明表锁造成的阻塞比较严重
Innodb_row_lock_waits innodb行锁，太大可能是间隙锁造成的
(9)复制延时量
mysql > show slave status
查看延时时间
(10) Tmp Table 状况(临时表状况)
mysql > show status like 'Create_tmp%';
Created_tmp_disk_tables/Created_tmp_tables比值最好不要超过10%，如果Created_tmp_tables值比较大，
可能是排序句子过多或者是连接句子不够优化
(11) Binlog Cache 使用状况
mysql > show status like 'Binlog_cache%';
如果Binlog_cache_disk_use值不为0 ，可能需要调大 binlog_cache_size大小
(12) Innodb_log_waits 量
mysql > show status like 'innodb_log_waits';
Innodb_log_waits值不等于0的话，表明 innodb log buffer 因为空间不足而等待
比如命令：
>#show global status;
虽然可以使用：
>#show global status like %...%;
来过滤，但是对应长长的list，每一项都代表什么意思，还是有必要弄清楚。
