• mysql show processlist详解


    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)。

    [plain] view plain copy
     
     print?
    1. mysql> show full processlist;  
    2. +---------+-------------+--------------------+----------------+-------------+-------+-----------------------------------------------------------------------+-----------------------+  
    3. | Id      | User        | Host               | db             | Command     | Time  | State                                                                 | Info                  |  
    4. +---------+-------------+--------------------+----------------+-------------+-------+-----------------------------------------------------------------------+-----------------------+  
    5. | 1056536 | replication | 192.168.6.91:38417 | NULL           | Binlog Dump | 33759 | Master has sent all binlog to slave; waiting for binlog to be updated | NULL                  |  
    6. | 1107067 | miaohr      | 192.168.6.81:32024 | NULL           | Query       |     0 | NULL                                                                  | show full processlist |  
    7. | 1107182 | miaohr      | 192.168.6.91:44217 | hr_db_business | Sleep       |     1 |                                                                       | NULL                  |  
    8. +---------+-------------+--------------------+----------------+-------------+-------+-----------------------------------------------------------------------+-----------------------+  



    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
     被其他查询锁住了。
    Sending data
     正在处理SELECT查询的记录,同时正在把结果发送给客户端。
    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;

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     print?
    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%'

    [plain] view plain copy
     
     print?
      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                                                                                                                         
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  • 原文地址:https://www.cnblogs.com/bethal/p/5320464.html
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