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MySQL?????????????????100?

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????????????????????

show processlist;

????????100?????????????????????????

show full processlist;

????????????????

???root??????????????????????????????????????

?????????

????MySQL??????????????????

show status;

???????????????????????

show status like '%????%';

?????????????????????

?????????????

• Aborted_clients??????????
• Aborted_connects?????????????
• Connections?????MySQL????????
• Created_tmp_tables?????????????????
• Delayed_insert_threads?????????????????
• Delayed_writes???INSERT DELAYED??????
• Flush_commands???FLUSH??????
• Handler_delete????????????
• Handler_read_first??????????????
• Handler_read_key????????????
• Handler_read_next??????????????
• Handler_read_rnd???????????????
• Handler_update???????????
• Handler_write????????????
• Key_blocks_used???????????
• Key_read_requests???????????????
• Key_reads?????????????
• Key_write_requests??????????????
• Key_writes??????????????
• Max_used_connections??????????????
• Not_flushed_key_blocks?????????????
• Not_flushed_delayed_rows??INSERT DELAY???????????
• Open_tables??????????
• Open_files?????????
• Open_streams??????????????????
• Opened_tables??????????
• Questions?????????????
• Slow_queries?????long_query_time??????
• Threads_connected???????????
• Threads_running?????????????
• Uptime?????????????

my.ini??

????MySQL???????my.ini??????????????????

• innodb_buffer_pool_size=576M?InnoDB??????????128M??
• query_cache_size=100M??????????32M??
• tmp_table_size=102M?????????32M??
• key_buffer_size=16m?????????8M??

???????

??????MySQL??????????100??????????????????????

??????my.cnf????

vi /etc/my.cnf

[mysqld]max_connections=32000#set-variable=max_user_connections=30  # ?????????#set-variable=max_connections=800    # ???????

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• ???????32000????MySQL????????????16384?
• ?max_connections???????????????????
• ??????????????????????
• ??????my.ini???????????????????

???????????

??????????????????????

mysql -uusername -ppassword -e "set GLOBAL max_connections=200;"

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show processlist;show status;

??mysqladmin????

???????????????????mysqladmin???

mysqladmin -uusername -ppassword variables

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????????????????????MySQL?????????????