mysql show processlist命令 详解

时间:2021-12-12 21:10:07

SHOW PROCESSLIST显示哪些线程正在运行。您也可以使用mysqladmin processlist语句得到此信息。如果您有SUPER权限,您可以看到所有线程。否则,您只能看到您自己的线程(也就是,与您正在使用的MySQL账户相关的线程)。请参见13.5.5.3节,“KILL语法”。如果您不使用FULL关键词,则只显示每个查询的前100个字符。

本语句报告TCP/IP连接的主机名称(采用host_name:client_port格式),以方便地判定哪个客户端正在做什么。

如果您得到“too many connections”错误信息,并且想要了解正在发生的情况,本语句是非常有用的。MySQL保留一个额外的连接,让拥有SUPER权限的 账户使用,以确保管理员能够随时连接和检查系统(假设您没有把此权限给予所有的用户)。

mysql> show full processlist\G;
*************************** 1. row ***************************
Id: 3
User: root
Host: 10.202.11.118:26602
db: ud_omcs
Command: Sleep
Time: 9
State:
Info: NULL
*************************** 2. row ***************************
Id: 208
User: root
Host: 10.202.37.75:40383
db: ud_omcs
Command: Sleep
Time: 3
State:
Info: NULL
*************************** 3. row ***************************
Id: 435
User: root
Host: 10.118.62.108:54675
db: route
Command: Sleep
Time: 1875
State:
Info: NULL
*************************** 4. row ***************************
Id: 446
User: root
Host: 10.118.62.108:54799
db: route
Command: Query
Time: 2950
State: Sending data
Info: update bas_vehicle_mline_info m left join bas_vehicle_zone_info z on m.req_line_id = z.req_line_id left join bas_vehicle_cargo_info c on z.req_zone_id = c.req_zone_id SET m.is_sync=2,z.is_sync=2,c.is_sync=2 WHERE m.is_sync = 0 and m.line_id in(10000001, 10000002, 10000003, 10000004, 10000005, 10000006, 10000007, 10000008, 10000009, 10000010, 10000011, 10000012, 10000013, 10000014, 10000015, 10000016, 10000017, 10000018, 10000019, 10000020)
*************************** 5. row ***************************
Id: 458
User: root
Host: localhost
db: route
Command: Query
Time: 0
State: starting
Info: show full processlist
5 rows in set (0.00 sec) ERROR:
No query specified mysql>

1、各列说明

先简单说一下各列的含义和用途,

第一列:id,不用说了吧,一个标识,你要kill一个语句的时候很有用。

user列:显示单前用户,如果不是root,这个命令就只显示你权限范围内的sql语句。

host列:显示这个语句是从哪个ip的哪个端口上发出的。呵呵,可以用来追踪出问题语句的用户。

db列:显示这个进程目前连接的是哪个数据库。

command列:显示当前连接的执行的命令,一般就是休眠(sleep),查询(query),连接(connect)。

time列:此这个状态持续的时间,单位是秒。

state列:显示使用当前连接的sql语句的状态,很重要的列,后续会有所有的状态的描述,请注意,state只是语句执行中的某一个状态,一个sql语句,已查询为例,可能需要经过copying to tmp table,Sorting result,Sending data等状态才可以完成。

info列:显示这个sql语句,因为长度有限,所以长的sql语句就显示不全,但是一个判断问题语句的重要依据。

2、这个命令中最关键的就是state列,mysql列出的状态主要有以下几种:

Checking table
 正在检查数据表(这是自动的)。
Closing tables
 正在将表中修改的数据刷新到磁盘中,同时正在关闭已经用完的表。这是一个很快的操作,如果不是这样的话,就应该确认磁盘空间是否已经满了或者磁盘是否正处于重负中。
Connect Out
 复制从服务器正在连接主服务器。
Copying to tmp table on disk
 由于临时结果集大于tmp_table_size,正在将临时表从内存存储转为磁盘存储以此节省内存。
Creating tmp table
 正在创建临时表以存放部分查询结果。
deleting from main table
 服务器正在执行多表删除中的第一部分,刚删除第一个表。
deleting from reference tables
 服务器正在执行多表删除中的第二部分,正在删除其他表的记录。
Flushing tables
 正在执行FLUSH TABLES,等待其他线程关闭数据表。
Killed
 发送了一个kill请求给某线程,那么这个线程将会检查kill标志位,同时会放弃下一个kill请求。MySQL会在每次的主循环中检查kill标志位,不过有些情况下该线程可能会过一小段才能死掉。如果该线程程被其他线程锁住了,那么kill请求会在锁释放时马上生效。
Locked
   在mysql服务器层,该线程正在等待表锁,在存储引擎级别实现的锁,例如,innoDB的行锁,并不会体现在线程状态中。对应MyISAM来说这是一个比较典型的状态,但在其他没有行锁的引擎中也经常会出现。
Sending data
 这个有多种情况,线程可能在多个状态之间传递数据,或者在生成结果集,或者在向客户端返回数据。
Sorting for group
 正在为GROUP BY做排序。
Sorting for order
 正在为ORDER BY做排序。
Opening tables
 这个过程应该会很快,除非受到其他因素的干扰。例如,在执ALTER TABLE或LOCK TABLE语句行完以前,数据表无法被其他线程打开。正尝试打开一个表。
Removing duplicates
 正在执行一个SELECT DISTINCT方式的查询,但是MySQL无法在前一个阶段优化掉那些重复的记录。因此,MySQL需要再次去掉重复的记录,然后再把结果发送给客户端。
Reopen table
 获得了对一个表的锁,但是必须在表结构修改之后才能获得这个锁。已经释放锁,关闭数据表,正尝试重新打开数据表。
Repair by sorting
 修复指令正在排序以创建索引。
Repair with keycache
 修复指令正在利用索引缓存一个一个地创建新索引。它会比Repair by sorting慢些。
Searching rows for update
 正在讲符合条件的记录找出来以备更新。它必须在UPDATE要修改相关的记录之前就完成了。
Sleeping
 正在等待客户端发送新请求.
System lock
 正在等待取得一个外部的系统锁。如果当前没有运行多个mysqld服务器同时请求同一个表,那么可以通过增加--skip-external-locking参数来禁止外部系统锁。
Upgrading lock
 INSERT DELAYED正在尝试取得一个锁表以插入新记录。
Updating
 正在搜索匹配的记录,并且修改它们。
User Lock
 正在等待GET_LOCK()。
Waiting for tables
 该线程得到通知,数据表结构已经被修改了,需要重新打开数据表以取得新的结构。然后,为了能的重新打开数据表,必须等到所有其他线程关闭这个表。以下几种情况下会产生这个通知:FLUSH TABLES tbl_name, ALTER TABLE, RENAME TABLE, REPAIR TABLE, ANALYZE TABLE,或OPTIMIZE TABLE。
waiting for handler insert
 INSERT DELAYED已经处理完了所有待处理的插入操作,正在等待新的请求。
 大部分状态对应很快的操作,只要有一个线程保持同一个状态好几秒钟,那么可能是有问题发生了,需要检查一下。
 还有其他的状态没在上面中列出来,不过它们大部分只是在查看服务器是否有存在错误是才用得着。

mysql 查看当前连接数

命令: show processlist; 
如果是root帐号,你能看到所有用户的当前连接。如果是其它普通帐号,只能看到自己占用的连接。 
show processlist;只列出前100条,如果想全列出请使用show full processlist; 
mysql> show processlist;

命令: show status;

  1. mysql> show status;
  2. +------------------------------------------+----------------------+
  3. | Variable_name                            | Value                |
  4. +------------------------------------------+----------------------+
  5. | Aborted_clients                          | 777                  |
  6. | Aborted_connects                         | 16                   |
  7. | Binlog_cache_disk_use                    | 532                  |
  8. | Binlog_cache_use                         | 8333221              |
  9. | Binlog_stmt_cache_disk_use               | 0                    |
  10. | Binlog_stmt_cache_use                    | 18732                |
  11. | Bytes_received                           | 303                  |
  12. | Bytes_sent                               | 12460                |
  13. | Com_admin_commands                       | 0                    |
  14. | Com_assign_to_keycache                   | 0                    |
  15. | Com_alter_db                             | 0                    |
  16. | Com_alter_db_upgrade                     | 0                    |
  17. | Com_alter_event                          | 0                    |
  18. | Com_alter_function                       | 0                    |
  19. | Com_alter_procedure                      | 0                    |
  20. | Com_alter_server                         | 0                    |
  21. | Com_alter_table                          | 0                    |
  22. | Com_alter_tablespace                     | 0                    |
  23. | Com_analyze                              | 0                    |
  24. | Com_begin                                | 0                    |
  25. | Com_binlog                               | 0                    |
  26. | Com_call_procedure                       | 0                    |
  27. | Com_change_db                            | 0                    |
  28. | Com_change_master                        | 0                    |
  29. | Com_check                                | 0                    |
  30. | Com_checksum                             | 0                    |
  31. | Com_commit                               | 0                    |
  32. | Com_create_db                            | 0                    |
  33. | Com_create_event                         | 0                    |
  34. | Com_create_function                      | 0                    |
  35. | Com_create_index                         | 0                    |
  36. | Com_create_procedure                     | 0                    |
  37. | Com_create_server                        | 0                    |
  38. | Com_create_table                         | 0                    |
  39. | Com_create_trigger                       | 0                    |
  40. | Com_create_udf                           | 0                    |
  41. | Com_create_user                          | 0                    |
  42. | Com_create_view                          | 0                    |
  43. | Com_dealloc_sql                          | 0                    |
  44. | Com_delete                               | 0                    |
  45. | Com_delete_multi                         | 0                    |
  46. | Com_do                                   | 0                    |
  47. | Com_drop_db                              | 0                    |
  48. | Com_drop_event                           | 0                    |
  49. | Com_drop_function                        | 0                    |
  50. | Com_drop_index                           | 0                    |
  51. | Com_drop_procedure                       | 0                    |
  52. | Com_drop_server                          | 0                    |
  53. | Com_drop_table                           | 0                    |
  54. | Com_drop_trigger                         | 0                    |
  55. | Com_drop_user                            | 0                    |
  56. | Com_drop_view                            | 0                    |
  57. | Com_empty_query                          | 0                    |
  58. | Com_execute_sql                          | 0                    |
  59. | Com_flush                                | 0                    |
  60. | Com_grant                                | 0                    |
  61. | Com_ha_close                             | 0                    |
  62. | Com_ha_open                              | 0                    |
  63. | Com_ha_read                              | 0                    |
  64. | Com_help                                 | 0                    |
  65. | Com_insert                               | 0                    |
  66. | Com_insert_select                        | 0                    |
  67. | Com_install_plugin                       | 0                    |
  68. | Com_kill                                 | 0                    |
  69. | Com_load                                 | 0                    |
  70. | Com_lock_tables                          | 0                    |
  71. | Com_optimize                             | 0                    |
  72. | Com_preload_keys                         | 0                    |
  73. | Com_prepare_sql                          | 0                    |
  74. | Com_purge                                | 0                    |
  75. | Com_purge_before_date                    | 0                    |
  76. | Com_release_savepoint                    | 0                    |
  77. | Com_rename_table                         | 0                    |
  78. | Com_rename_user                          | 0                    |
  79. | Com_repair                               | 0                    |
  80. | Com_replace                              | 0                    |
  81. | Com_replace_select                       | 0                    |
  82. | Com_reset                                | 0                    |
  83. | Com_resignal                             | 0                    |
  84. | Com_revoke                               | 0                    |
  85. | Com_revoke_all                           | 0                    |
  86. | Com_rollback                             | 0                    |
  87. | Com_rollback_to_savepoint                | 0                    |
  88. | Com_savepoint                            | 0                    |
  89. | Com_select                               | 1                    |
  90. | Com_set_option                           | 0                    |
  91. | Com_signal                               | 0                    |
  92. | Com_show_authors                         | 0                    |
  93. | Com_show_binlog_events                   | 0                    |
  94. | Com_show_binlogs                         | 0                    |
  95. | Com_show_charsets                        | 0                    |
  96. | Com_show_collations                      | 0                    |
  97. | Com_show_contributors                    | 0                    |
  98. | Com_show_create_db                       | 0                    |
  99. | Com_show_create_event                    | 0                    |
  100. | Com_show_create_func                     | 0                    |
  101. | Com_show_create_proc                     | 0                    |
  102. | Com_show_create_table                    | 0                    |
  103. | Com_show_create_trigger                  | 0                    |
  104. | Com_show_databases                       | 0                    |
  105. | Com_show_engine_logs                     | 0                    |
  106. | Com_show_engine_mutex                    | 0                    |
  107. | Com_show_engine_status                   | 0                    |
  108. | Com_show_events                          | 0                    |
  109. | Com_show_errors                          | 0                    |
  110. | Com_show_fields                          | 0                    |
  111. | Com_show_function_status                 | 0                    |
  112. | Com_show_grants                          | 0                    |
  113. | Com_show_keys                            | 0                    |
  114. | Com_show_master_status                   | 0                    |
  115. | Com_show_open_tables                     | 0                    |
  116. | Com_show_plugins                         | 0                    |
  117. | Com_show_privileges                      | 0                    |
  118. | Com_show_procedure_status                | 0                    |
  119. | Com_show_processlist                     | 6                    |
  120. | Com_show_profile                         | 0                    |
  121. | Com_show_profiles                        | 0                    |
  122. | Com_show_relaylog_events                 | 0                    |
  123. | Com_show_slave_hosts                     | 0                    |
  124. | Com_show_slave_status                    | 0                    |
  125. | Com_show_status                          | 2                    |
  126. | Com_show_storage_engines                 | 0                    |
  127. | Com_show_table_status                    | 0                    |
  128. | Com_show_tables                          | 0                    |
  129. | Com_show_triggers                        | 0                    |
  130. | Com_show_variables                       | 0                    |
  131. | Com_show_warnings                        | 0                    |
  132. | Com_slave_start                          | 0                    |
  133. | Com_slave_stop                           | 0                    |
  134. | Com_stmt_close                           | 0                    |
  135. | Com_stmt_execute                         | 0                    |
  136. | Com_stmt_fetch                           | 0                    |
  137. | Com_stmt_prepare                         | 0                    |
  138. | Com_stmt_reprepare                       | 0                    |
  139. | Com_stmt_reset                           | 0                    |
  140. | Com_stmt_send_long_data                  | 0                    |
  141. | Com_truncate                             | 0                    |
  142. | Com_uninstall_plugin                     | 0                    |
  143. | Com_unlock_tables                        | 0                    |
  144. | Com_update                               | 0                    |
  145. | Com_update_multi                         | 0                    |
  146. | Com_xa_commit                            | 0                    |
  147. | Com_xa_end                               | 0                    |
  148. | Com_xa_prepare                           | 0                    |
  149. | Com_xa_recover                           | 0                    |
  150. | Com_xa_rollback                          | 0                    |
  151. | Com_xa_start                             | 0                    |
  152. | Compression                              | OFF                  |
  153. | Connections                              | 1107216              |
  154. | Created_tmp_disk_tables                  | 0                    |
  155. | Created_tmp_files                        | 564                  |
  156. | Created_tmp_tables                       | 0                    |
  157. | Delayed_errors                           | 0                    |
  158. | Delayed_insert_threads                   | 0                    |
  159. | Delayed_writes                           | 0                    |
  160. | Flush_commands                           | 1                    |
  161. | Handler_commit                           | 0                    |
  162. | Handler_delete                           | 0                    |
  163. | Handler_discover                         | 0                    |
  164. | Handler_prepare                          | 0                    |
  165. | Handler_read_first                       | 0                    |
  166. | Handler_read_key                         | 0                    |
  167. | Handler_read_last                        | 0                    |
  168. | Handler_read_next                        | 0                    |
  169. | Handler_read_prev                        | 0                    |
  170. | Handler_read_rnd                         | 0                    |
  171. | Handler_read_rnd_next                    | 0                    |
  172. | Handler_rollback                         | 0                    |
  173. | Handler_savepoint                        | 0                    |
  174. | Handler_savepoint_rollback               | 0                    |
  175. | Handler_update                           | 0                    |
  176. | Handler_write                            | 0                    |
  177. | Innodb_buffer_pool_pages_data            | 376178               |
  178. | Innodb_buffer_pool_bytes_data            | 4261109760           |
  179. | Innodb_buffer_pool_pages_dirty           | 0                    |
  180. | Innodb_buffer_pool_bytes_dirty           | 0                    |
  181. | Innodb_buffer_pool_pages_flushed         | 4419408              |
  182. | Innodb_buffer_pool_pages_free            | 0                    |
  183. | Innodb_buffer_pool_pages_misc            | 18446744073709437581 |
  184. | Innodb_buffer_pool_pages_total           | 262143               |
  185. | Innodb_buffer_pool_read_ahead_rnd        | 0                    |
  186. | Innodb_buffer_pool_read_ahead            | 506357               |
  187. | Innodb_buffer_pool_read_ahead_evicted    | 49891                |
  188. | Innodb_buffer_pool_read_requests         | 3550554620           |
  189. | Innodb_buffer_pool_reads                 | 8777938              |
  190. | Innodb_buffer_pool_wait_free             | 0                    |
  191. | Innodb_buffer_pool_write_requests        | 159577779            |
  192. | Innodb_data_fsyncs                       | 13359191             |
  193. | Innodb_data_pending_fsyncs               | 0                    |
  194. | Innodb_data_pending_reads                | 0                    |
  195. | Innodb_data_pending_writes               | 0                    |
  196. | Innodb_data_read                         | 133311885312         |
  197. | Innodb_data_reads                        | 9323868              |
  198. | Innodb_data_writes                       | 17580993             |
  199. | Innodb_data_written                      | 163731449856         |
  200. | Innodb_dblwr_pages_written               | 4419408              |
  201. | Innodb_dblwr_writes                      | 119202               |
  202. | Innodb_have_atomic_builtins              | ON                   |
  203. | Innodb_log_waits                         | 0                    |
  204. | Innodb_log_write_requests                | 39730223             |
  205. | Innodb_log_writes                        | 12957426             |
  206. | Innodb_os_log_fsyncs                     | 13004841             |
  207. | Innodb_os_log_pending_fsyncs             | 0                    |
  208. | Innodb_os_log_pending_writes             | 0                    |
  209. | Innodb_os_log_written                    | 25546702336          |
  210. | Innodb_page_size                         | 16384                |
  211. | Innodb_pages_created                     | 539547               |
  212. | Innodb_pages_read                        | 9323581              |
  213. | Innodb_pages_written                     | 4419408              |
  214. | Innodb_row_lock_current_waits            | 0                    |
  215. | Innodb_row_lock_time                     | 26866245             |
  216. | Innodb_row_lock_time_avg                 | 1367                 |
  217. | Innodb_row_lock_time_max                 | 55497                |
  218. | Innodb_row_lock_waits                    | 19649                |
  219. | Innodb_rows_deleted                      | 15511                |
  220. | Innodb_rows_inserted                     | 1868056              |
  221. | Innodb_rows_read                         | 1657696248           |
  222. | Innodb_rows_updated                      | 7778106              |
  223. | Innodb_truncated_status_writes           | 0                    |
  224. | Key_blocks_not_flushed                   | 0                    |
  225. | Key_blocks_unused                        | 26773                |
  226. | Key_blocks_used                          | 19                   |
  227. | Key_read_requests                        | 67555                |
  228. | Key_reads                                | 19                   |
  229. | Key_write_requests                       | 69364                |
  230. | Key_writes                               | 11544                |
  231. | Last_query_cost                          | 0.000000             |
  232. | Max_used_connections                     | 436                  |
  233. | Not_flushed_delayed_rows                 | 0                    |
  234. | Open_files                               | 99                   |
  235. | Open_streams                             | 0                    |
  236. | Open_table_definitions                   | 327                  |
  237. | Open_tables                              | 1301                 |
  238. | Opened_files                             | 22851                |
  239. | Opened_table_definitions                 | 0                    |
  240. | Opened_tables                            | 0                    |
  241. | Performance_schema_cond_classes_lost     | 0                    |
  242. | Performance_schema_cond_instances_lost   | 0                    |
  243. | Performance_schema_file_classes_lost     | 0                    |
  244. | Performance_schema_file_handles_lost     | 0                    |
  245. | Performance_schema_file_instances_lost   | 0                    |
  246. | Performance_schema_locker_lost           | 0                    |
  247. | Performance_schema_mutex_classes_lost    | 0                    |
  248. | Performance_schema_mutex_instances_lost  | 0                    |
  249. | Performance_schema_rwlock_classes_lost   | 0                    |
  250. | Performance_schema_rwlock_instances_lost | 0                    |
  251. | Performance_schema_table_handles_lost    | 0                    |
  252. | Performance_schema_table_instances_lost  | 0                    |
  253. | Performance_schema_thread_classes_lost   | 0                    |
  254. | Performance_schema_thread_instances_lost | 0                    |
  255. | Prepared_stmt_count                      | 0                    |
  256. | Qcache_free_blocks                       | 3426                 |
  257. | Qcache_free_memory                       | 38784160             |
  258. | Qcache_hits                              | 9223399              |
  259. | Qcache_inserts                           | 3505151              |
  260. | Qcache_lowmem_prunes                     | 0                    |
  261. | Qcache_not_cached                        | 400457               |
  262. | Qcache_queries_in_cache                  | 19336                |
  263. | Qcache_total_blocks                      | 42289                |
  264. | Queries                                  | 27883378             |
  265. | Questions                                | 9                    |
  266. | Rpl_status                               | AUTH_MASTER          |
  267. | Select_full_join                         | 0                    |
  268. | Select_full_range_join                   | 0                    |
  269. | Select_range                             | 0                    |
  270. | Select_range_check                       | 0                    |
  271. | Select_scan                              | 0                    |
  272. | Slave_heartbeat_period                   | 0.000                |
  273. | Slave_open_temp_tables                   | 0                    |
  274. | Slave_received_heartbeats                | 0                    |
  275. | Slave_retried_transactions               | 0                    |
  276. | Slave_running                            | OFF                  |
  277. | Slow_launch_threads                      | 30                   |
  278. | Slow_queries                             | 0                    |
  279. | Sort_merge_passes                        | 0                    |
  280. | Sort_range                               | 0                    |
  281. | Sort_rows                                | 0                    |
  282. | Sort_scan                                | 0                    |
  283. | Ssl_accept_renegotiates                  | 0                    |
  284. | Ssl_accepts                              | 0                    |
  285. | Ssl_callback_cache_hits                  | 0                    |
  286. | Ssl_cipher                               |                      |
  287. | Ssl_cipher_list                          |                      |
  288. | Ssl_client_connects                      | 0                    |
  289. | Ssl_connect_renegotiates                 | 0                    |
  290. | Ssl_ctx_verify_depth                     | 0                    |
  291. | Ssl_ctx_verify_mode                      | 0                    |
  292. | Ssl_default_timeout                      | 0                    |
  293. | Ssl_finished_accepts                     | 0                    |
  294. | Ssl_finished_connects                    | 0                    |
  295. | Ssl_session_cache_hits                   | 0                    |
  296. | Ssl_session_cache_misses                 | 0                    |
  297. | Ssl_session_cache_mode                   | NONE                 |
  298. | Ssl_session_cache_overflows              | 0                    |
  299. | Ssl_session_cache_size                   | 0                    |
  300. | Ssl_session_cache_timeouts               | 0                    |
  301. | Ssl_sessions_reused                      | 0                    |
  302. | Ssl_used_session_cache_entries           | 0                    |
  303. | Ssl_verify_depth                         | 0                    |
  304. | Ssl_verify_mode                          | 0                    |
  305. | Ssl_version                              |                      |
  306. | Table_locks_immediate                    | 13127661             |
  307. | Table_locks_waited                       | 648                  |
  308. | Tc_log_max_pages_used                    | 0                    |
  309. | Tc_log_page_size                         | 0                    |
  310. | Tc_log_page_waits                        | 6                    |
  311. | Threads_cached                           | 7                    |
  312. | Threads_connected                        | 2                    |
  313. | Threads_created                          | 54593                |
  314. | Threads_running                          | 2                    |
  315. | Uptime                                   | 651324               |
  316. | Uptime_since_flush_status                | 651324               |
  317. +------------------------------------------+----------------------+
  318. 312 rows in set (0.01 sec)

Aborted_clients 由于客户没有正确关闭连接已经死掉,已经放弃的连接数量。 
Aborted_connects 尝试已经失败的MySQL服务器的连接的次数。 
Connections 试图连接MySQL服务器的次数。 
Created_tmp_tables 当执行语句时,已经被创造了的隐含临时表的数量。 
Delayed_insert_threads 正在使用的延迟插入处理器线程的数量。 
Delayed_writes 用INSERT DELAYED写入的行数。 
Delayed_errors 用INSERT DELAYED写入的发生某些错误(可能重复键值)的行数。 
Flush_commands 执行FLUSH命令的次数。 
Handler_delete 请求从一张表中删除行的次数。 
Handler_read_first 请求读入表中第一行的次数。 
Handler_read_key 请求数字基于键读行。 
Handler_read_next 请求读入基于一个键的一行的次数。 
Handler_read_rnd 请求读入基于一个固定位置的一行的次数。 
Handler_update 请求更新表中一行的次数。 
Handler_write 请求向表中插入一行的次数。 
Key_blocks_used 用于关键字缓存的块的数量。 
Key_read_requests 请求从缓存读入一个键值的次数。 
Key_reads 从磁盘物理读入一个键值的次数。 
Key_write_requests 请求将一个关键字块写入缓存次数。 
Key_writes 将一个键值块物理写入磁盘的次数。 
Max_used_connections 同时使用的连接的最大数目。 
Not_flushed_key_blocks 在键缓存中已经改变但是还没被清空到磁盘上的键块。 
Not_flushed_delayed_rows 在INSERT DELAY队列中等待写入的行的数量。 
Open_tables 打开表的数量。 
Open_files 打开文件的数量。 
Open_streams 打开流的数量(主要用于日志记载) 
Opened_tables 已经打开的表的数量。 
Questions 发往服务器的查询的数量。 
Slow_queries 要花超过long_query_time时间的查询数量。 
Threads_connected 当前打开的连接的数量。 
Threads_running 不在睡眠的线程数量。

Uptime 服务器工作了多少秒。

查看配置参数:

SHOW VARIABLES LIKE '%timeout%'

    1. Variable_name                                      Value
    2. -------------------------------------------------  ------------------------------------------------------------------------------------------------------------------------
    3. auto_increment_increment                           1
    4. auto_increment_offset                              1
    5. autocommit                                         ON
    6. automatic_sp_privileges                            ON
    7. back_log                                           384
    8. basedir                                            /usr
    9. big_tables                                         OFF
    10. binlog_cache_size                                  1048576
    11. binlog_direct_non_transactional_updates            OFF
    12. binlog_format                                      MIXED
    13. binlog_stmt_cache_size                             32768
    14. bulk_insert_buffer_size                            67108864
    15. character_set_client                               utf8
    16. character_set_connection                           utf8
    17. character_set_database                             utf8
    18. character_set_filesystem                           binary
    19. character_set_results                              utf8
    20. character_set_server                               utf8
    21. character_set_system                               utf8
    22. character_sets_dir                                 /usr/share/mysql/charsets/
    23. collation_connection                               utf8_general_ci
    24. collation_database                                 utf8_general_ci
    25. collation_server                                   utf8_general_ci
    26. completion_type                                    NO_CHAIN
    27. concurrent_insert                                  AUTO
    28. connect_timeout                                    10
    29. datadir                                            /var/lib/mysql/
    30. date_format                                        %Y-%m-%d
    31. datetime_format                                    %Y-%m-%d %H:%i:%s
    32. default_storage_engine                             InnoDB
    33. default_week_format                                0
    34. delay_key_write                                    ON
    35. delayed_insert_limit                               100
    36. delayed_insert_timeout                             300
    37. delayed_queue_size                                 1000
    38. div_precision_increment                            4
    39. engine_condition_pushdown                          ON
    40. error_count                                        0
    41. event_scheduler                                    OFF
    42. expire_logs_days                                   30
    43. external_user
    44. flush                                              OFF
    45. flush_time                                         0
    46. foreign_key_checks                                 ON
    47. ft_boolean_syntax                                  + -><()~*:""&|
    48. ft_max_word_len                                    84
    49. ft_min_word_len                                    4
    50. ft_query_expansion_limit                           20
    51. ft_stopword_file                                   (built-in)
    52. general_log                                        OFF
    53. general_log_file                                   /var/lib/mysql/VM84.log
    54. group_concat_max_len                               1024
    55. have_compress                                      YES
    56. have_crypt                                         YES
    57. have_csv                                           YES
    58. have_dynamic_loading                               YES
    59. have_geometry                                      YES
    60. have_innodb                                        YES
    61. have_ndbcluster                                    NO
    62. have_openssl                                       DISABLED
    63. have_partitioning                                  YES
    64. have_profiling                                     YES
    65. have_query_cache                                   YES
    66. have_rtree_keys                                    YES
    67. have_ssl                                           DISABLED
    68. have_symlink                                       YES
    69. hostname                                           VM84
    70. identity                                           0
    71. ignore_builtin_innodb                              OFF
    72. init_connect
    73. init_file
    74. init_slave
    75. innodb_adaptive_flushing                           ON
    76. innodb_adaptive_hash_index                         ON
    77. innodb_additional_mem_pool_size                    16777216
    78. innodb_autoextend_increment                        8
    79. innodb_autoinc_lock_mode                           1
    80. innodb_buffer_pool_instances                       1
    81. innodb_buffer_pool_size                            4294967296
    82. innodb_change_buffering                            all
    83. innodb_checksums                                   ON
    84. innodb_commit_concurrency                          0
    85. innodb_concurrency_tickets                         500
    86. innodb_data_file_path                              ibdata1:10M:autoextend
    87. innodb_data_home_dir
    88. innodb_doublewrite                                 ON
    89. innodb_fast_shutdown                               1
    90. innodb_file_format                                 Antelope
    91. innodb_file_format_check                           ON
    92. innodb_file_format_max                             Antelope
    93. innodb_file_per_table                              ON
    94. innodb_flush_log_at_trx_commit                     2
    95. innodb_flush_method
    96. innodb_force_load_corrupted                        OFF
    97. innodb_force_recovery                              0
    98. innodb_io_capacity                                 200
    99. innodb_large_prefix                                OFF
    100. innodb_lock_wait_timeout                           50
    101. innodb_locks_unsafe_for_binlog                     OFF
    102. innodb_log_buffer_size                             16777216
    103. innodb_log_file_size                               536870912
    104. innodb_log_files_in_group                          2
    105. innodb_log_group_home_dir                          ./
    106. innodb_max_dirty_pages_pct                         75
    107. innodb_max_purge_lag                               0
    108. innodb_mirrored_log_groups                         1
    109. innodb_old_blocks_pct                              37
    110. innodb_old_blocks_time                             0
    111. innodb_open_files                                  300
    112. innodb_print_all_deadlocks                         OFF
    113. innodb_purge_batch_size                            20
    114. innodb_purge_threads                               0
    115. innodb_random_read_ahead                           OFF
    116. innodb_read_ahead_threshold                        56
    117. innodb_read_io_threads                             4
    118. innodb_replication_delay                           0
    119. innodb_rollback_on_timeout                         OFF
    120. innodb_rollback_segments                           128
    121. innodb_spin_wait_delay                             6
    122. innodb_stats_method                                nulls_equal
    123. innodb_stats_on_metadata                           ON
    124. innodb_stats_sample_pages                          8
    125. innodb_strict_mode                                 OFF
    126. innodb_support_xa                                  ON
    127. innodb_sync_spin_loops                             30
    128. innodb_table_locks                                 ON
    129. innodb_thread_concurrency                          0
    130. innodb_thread_sleep_delay                          10000
    131. innodb_use_native_aio                              ON
    132. innodb_use_sys_malloc                              ON
    133. innodb_version                                     5.5.36
    134. innodb_write_io_threads                            4
    135. insert_id                                          0
    136. interactive_timeout                                300
    137. join_buffer_size                                   8388608
    138. keep_files_on_create                               OFF
    139. key_buffer_size                                    33554432
    140. key_cache_age_threshold                            300
    141. key_cache_block_size                               1024
    142. key_cache_division_limit                           100
    143. large_files_support                                ON
    144. large_page_size                                    0
    145. large_pages                                        OFF
    146. last_insert_id                                     0
    147. lc_messages                                        en_US
    148. lc_messages_dir                                    /usr/share/mysql/
    149. lc_time_names                                      en_US
    150. license                                            GPL
    151. local_infile                                       ON
    152. lock_wait_timeout                                  31536000
    153. locked_in_memory                                   OFF
    154. log                                                OFF
    155. log_bin                                            ON
    156. log_bin_trust_function_creators                    OFF
    157. log_error                                          /var/lib/mysql/VM84.err
    158. log_output                                         FILE
    159. log_queries_not_using_indexes                      OFF
    160. log_slave_updates                                  OFF
    161. log_slow_queries                                   ON
    162. log_warnings                                       1
    163. long_query_time                                    2.000000
    164. low_priority_updates                               OFF
    165. lower_case_file_system                             OFF
    166. lower_case_table_names                             0
    167. max_allowed_packet                                 16777216
    168. max_binlog_cache_size                              18446744073709547520
    169. max_binlog_size                                    1073741824
    170. max_binlog_stmt_cache_size                         18446744073709547520
    171. max_connect_errors                                 1024
    172. max_connections                                    2048
    173. max_delayed_threads                                20
    174. max_error_count                                    64
    175. max_heap_table_size                                67108864
    176. max_insert_delayed_threads                         20
    177. max_join_size                                      18446744073709551615
    178. max_length_for_sort_data                           1024
    179. max_long_data_size                                 16777216
    180. max_prepared_stmt_count                            16382
    181. max_relay_log_size                                 0
    182. max_seeks_for_key                                  18446744073709551615
    183. max_sort_length                                    1024
    184. max_sp_recursion_depth                             0
    185. max_tmp_tables                                     32
    186. max_user_connections                               0
    187. max_write_lock_count                               18446744073709551615
    188. metadata_locks_cache_size                          1024
    189. min_examined_row_limit                             0
    190. multi_range_count                                  256
    191. myisam_data_pointer_size                           6
    192. myisam_max_sort_file_size                          21474836480
    193. myisam_mmap_size                                   18446744073709551615
    194. myisam_recover_options                             DEFAULT
    195. myisam_repair_threads                              1
    196. myisam_sort_buffer_size                            536870912
    197. myisam_stats_method                                nulls_unequal
    198. myisam_use_mmap                                    OFF
    199. net_buffer_length                                  16384
    200. net_read_timeout                                   30
    201. net_retry_count                                    10
    202. net_write_timeout                                  60
    203. new                                                OFF
    204. old                                                OFF
    205. old_alter_table                                    OFF
    206. old_passwords                                      OFF
    207. open_files_limit                                   65535
    208. optimizer_prune_level                              1
    209. optimizer_search_depth                             62
    210. optimizer_switch                                   index_merge=on,index_merge_union=on,index_merge_sort_union=on,index_merge_intersection=on,engine_condition_pushdown=on
    211. performance_schema                                 OFF
    212. performance_schema_events_waits_history_long_size  10000
    213. performance_schema_events_waits_history_size       10
    214. performance_schema_max_cond_classes                80
    215. performance_schema_max_cond_instances              1000
    216. performance_schema_max_file_classes                50
    217. performance_schema_max_file_handles                32768
    218. performance_schema_max_file_instances              10000
    219. performance_schema_max_mutex_classes               200
    220. performance_schema_max_mutex_instances             1000000
    221. performance_schema_max_rwlock_classes              30
    222. performance_schema_max_rwlock_instances            1000000
    223. performance_schema_max_table_handles               100000
    224. performance_schema_max_table_instances             50000
    225. performance_schema_max_thread_classes              50
    226. performance_schema_max_thread_instances            1000
    227. pid_file                                           /var/run/mysqld/mysqld.pid
    228. plugin_dir                                         /usr/lib64/mysql/plugin/
    229. port                                               3306
    230. preload_buffer_size                                32768
    231. profiling                                          OFF
    232. profiling_history_size                             15
    233. protocol_version                                   10
    234. proxy_user
    235. pseudo_slave_mode                                  OFF
    236. pseudo_thread_id                                   2634591
    237. query_alloc_block_size                             8192
    238. query_cache_limit                                  2097152
    239. query_cache_min_res_unit                           4096
    240. query_cache_size                                   67108864
    241. query_cache_type                                   ON
    242. query_cache_wlock_invalidate                       OFF
    243. query_prealloc_size                                8192
    244. rand_seed1                                         0
    245. rand_seed2                                         0
    246. range_alloc_block_size                             4096
    247. read_buffer_size                                   2097152
    248. read_only                                          OFF
    249. read_rnd_buffer_size                               16777216
    250. relay_log
    251. relay_log_index
    252. relay_log_info_file                                relay-log.info
    253. relay_log_purge                                    ON
    254. relay_log_recovery                                 OFF
    255. relay_log_space_limit                              0
    256. report_host
    257. report_password
    258. report_port                                        3306
    259. report_user
    260. rpl_recovery_rank                                  0
    261. secure_auth                                        OFF
    262. secure_file_priv
    263. server_id                                          84
    264. skip_external_locking                              ON
    265. skip_name_resolve                                  ON
    266. skip_networking                                    OFF
    267. skip_show_database                                 OFF
    268. slave_compressed_protocol                          OFF
    269. slave_exec_mode                                    STRICT
    270. slave_load_tmpdir                                  /tmp
    271. slave_max_allowed_packet                           1073741824
    272. slave_net_timeout                                  3600
    273. slave_skip_errors                                  1032,1062
    274. slave_transaction_retries                          10
    275. slave_type_conversions
    276. slow_launch_time                                   2
    277. slow_query_log                                     ON
    278. slow_query_log_file                                /var/lib/mysql/VM84-slow.log
    279. socket                                             /var/lib/mysql/mysql.sock
    280. sort_buffer_size                                   8388608
    281. sql_auto_is_null                                   OFF
    282. sql_big_selects                                    ON
    283. sql_big_tables                                     OFF
    284. sql_buffer_result                                  OFF
    285. sql_log_bin                                        ON
    286. sql_log_off                                        OFF
    287. sql_low_priority_updates                           OFF
    288. sql_max_join_size                                  18446744073709551615
    289. sql_mode
    290. sql_notes                                          ON
    291. sql_quote_show_create                              ON
    292. sql_safe_updates                                   OFF
    293. sql_select_limit                                   18446744073709551615
    294. sql_slave_skip_counter                             0
    295. sql_warnings                                       OFF
    296. ssl_ca
    297. ssl_capath
    298. ssl_cert
    299. ssl_cipher
    300. ssl_key
    301. storage_engine                                     InnoDB
    302. stored_program_cache                               256
    303. sync_binlog                                        0
    304. sync_frm                                           ON
    305. sync_master_info                                   0
    306. sync_relay_log                                     0
    307. sync_relay_log_info                                0
    308. system_time_zone                                   CST
    309. table_definition_cache                             400
    310. table_open_cache                                   2048
    311. thread_cache_size                                  8
    312. thread_concurrency                                 16
    313. thread_handling                                    one-thread-per-connection
    314. thread_stack                                       262144
    315. time_format                                        %H:%i:%s
    316. time_zone                                          SYSTEM
    317. timed_mutexes                                      OFF
    318. timestamp                                          1408104399
    319. tmp_table_size                                     67108864
    320. tmpdir                                             /tmp
    321. transaction_alloc_block_size                       8192
    322. transaction_prealloc_size                          4096
    323. tx_isolation                                       REPEATABLE-READ
    324. unique_checks                                      ON
    325. updatable_views_with_limit                         YES
    326. version                                            5.5.36-log
    327. version_comment                                    MySQL Community Server (GPL) by Remi
    328. version_compile_machine                            x86_64
    329. version_compile_os                                 Linux
    330. wait_timeout                                       28800
    331. warning_count                                      0