Common commands used for monitoring in MYSQL database maintenance _mysql

Status = Show status like '% percent ' [example: Show status like ' Com_select ']
variables = Show variables like '% percent ' [Example: show variables like ' query_cache_size ']

1, MySQL query times (status)
Com_select; Com_update; Com_insert; Com_delete; com_change_db

2, query cache space size: query_cache_size (variables)
Query cache Maximum query DataSet size: Query_cache_limit (variables);
Number of queries in the cache: Qcache_inserts (status);
Query Cache Hit Ratio: (qcache_hits/(Qcache_hits+qcache_inserts)) *100% (status)

3. Index Cache Hit Ratio
Index cache space Size: key_buffer_size (variables)
Index cache Hit Ratio: (key_reads/key_read_requests) *100% (status)

4, concurrent connection number
Maximum allowable connection number: Max_connections (variables)
Actual maximum number of connections: max_used_connections (status)
Current number of connections: threads_connected (status)
Active connection Number: threads_running (status)
Number of cached connections: Threads_cache (status)

5, Traffic statistics (status)
Bytes_received, bytes_sent (status)

6, the number of connections
Number of connections per second: connections (status)
Actual number of connections per second: threads_created (status)

7, table lock statistics
Number of table locks released immediately: table_locks_immediate (status)
Number of table locks to wait: table_locks_waited (status)