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。
一，获取mysql用户下的进程总数
ps -ef | awk '{print $1}' | grep "mysql" | grep -v "grep" | wc-1
二，主机性能状态
# uptime
[root@ ~]# uptime
13:05:52 up 53 days, 52 min, 1 user, load average: 0.00, 0.00, 0.00
三，CPU使用率
# top
或
# vmstat
四，磁盘IO量
# vmstat 或 # iostat
五，swap进出量[内存]
# free
六，数据库性能状态
(1)QPS(每秒Query量)
QPS = Questions(or Queries) / seconds
mysql > show /*50000 global */ status like 'Question';
(2)TPS(每秒事务量)
TPS = (Com_commit + Com_rollback) / seconds
mysql > show status like 'Com_commit';
mysql > show status like 'Com_rollback';
(3)key Buffer 命中率
key_buffer_read_hits = (1-key_reads / key_read_requests) * 100%
key_buffer_write_hits = (1-key_writes / key_write_requests) * 100%
mysql> show status like 'Key%';
(4)InnoDB Buffer命中率
innodb_buffer_read_hits = (1 - innodb_buffer_pool_reads / innodb_buffer_pool_read_requests) * 100%
mysql> show status like 'innodb_buffer_pool_read%';
(5)Query Cache命中率
Query_cache_hits = (Qcahce_hits / (Qcache_hits + Qcache_inserts )) * 100%;
mysql> show status like 'Qcache%';
(6)Table Cache状态量
mysql> show status like 'open%';
(7)Thread Cache 命中率
Thread_cache_hits = (1 - Threads_created / connections ) * 100%
mysql> show status like 'Thread%';
mysql> show status like 'Connections';
(8)锁定状态
mysql> show status like '%lock%';
(9)复制延时量
mysql > show slave status
(10) Tmp Table 状况(临时表状况)
mysql > show status like 'Create_tmp%';
(11) Binlog Cache 使用状况
mysql > show status like 'Binlog_cache%';
(12) Innodb_log_waits 量
mysql > show status like 'innodb_log_waits';
开源监控软件
一，RRDTool
二，Nagios
三，MRTG
四，Cacti