MYSQL5.6重要引數
版本msyql5.6，原筆記上面的有些粗糙
一、線上mysql修改timeout值
show processlist;
set global interactive_timeout=400;
set global wait_timeout=400;
Exit
二、關於線上innodb引數使用情況
mysql> show global status like 'innodb_buffer_pool_pages%';
+----------------------------------+---------+
| Variable_name | Value |
+----------------------------------+---------+
| Innodb_buffer_pool_pages_data | 384598 | //使用頁
| Innodb_buffer_pool_pages_dirty | 476 |
| Innodb_buffer_pool_pages_flushed | 1329814 |
| Innodb_buffer_pool_pages_free | 3072 | //空閒頁
| Innodb_buffer_pool_pages_misc | 5544 |
| Innodb_buffer_pool_pages_total | 393214 | //總頁數
+----------------------------------+---------+
空閒頁面很多，說明設定過大，相反如果空閒頁面少，說明需要調大；
——————————————————————————————————
mysql> show variables like 'innodb_log%';
+-----------------------------+-----------+
| Variable_name | Value |
+-----------------------------+-----------+
| innodb_log_buffer_size | 8388608 | //把這次改動的記錄寫到日誌快取中
mysql> show global status like '%innodb_log_waits%';
+------------------+-------+
| Variable_name | Value |
+------------------+-------+
| Innodb_log_waits | 0 | //大於0,繼續增大，要調整innodb_log_buffer_size大小，取值16MB-64MB
+------------------+-------+
show global status like '%binlog_cache%';
ERROR 2006 (HY000): MySQL server has gone away
No connection. Trying to reconnect...
Connection id: 17122163
Current database: *** NONE ***
+-----------------------+--------+
| Variable_name | Value |
+-----------------------+--------+
| Binlog_cache_disk_use | 3306 | //不為0.說明磁碟上的臨時檔案被用上， 要調binlog_cache_size
| Binlog_cache_use | 593010 |
+-----------------------+--------+
mysqldumpslow -s t -t 10 /data/mysql/mysql-slow.log
查詢的結果是10條執行時間最慢的sql語句，其中-s t是指此類型別的語句的執
Time=3.73s (2205s) 最長的執行時間，2205統計用的時間
關於慢查詢 slow
Mysqldumpslow 不好用情況下，percona-toolkit工具，pt-query-digest
mysqldumpslow -s t -t 10 /data/mysql/mysql-slow.log
Pt-query-digest --since=24h /data/mysql/slow.log >query.log
分析24小時query.log overall 總有多少條查詢
Time range：查詢執行的時間範圍
Unique:唯一查詢數量
Total：
95%：小到大排列
Median：中位數
Pid檔案，將自己唯一程序號記錄到自己pid檔案中
Socket檔案：是伺服器與本地客戶端進行通訊的UNIX套接字檔案
對記錄做變更操作時不僅會產生redo記錄，也會產生undo記錄（insert update delete），但undo只記錄變更前的舊資料
Show global status
+-----------------------------------------------+---------------------+
| Variable_name | Value |
+-----------------------------------------------+---------------------+
| Aborted_clients | 70979 |//客戶端沒有正確關閉連線導致客戶端連線終止，以及連線超時
| Aborted_connects | 466 |//連線資料庫失敗的連線數
| Binlog_cache_disk_use | 3308 |//臨時二進位制日誌快取，是超過binlog_cache_size值並使用臨時檔案來儲存事務中語句的事務數量
| Binlog_cache_use | 599563 | //使用臨時二進位制日誌快取事物數量
| Binlog_stmt_cache_disk_use | 2741 |//當非事物語句使用二進位制日誌快取，但是超出binlog_stmt_cache_size大小時，就會使用一個臨時檔案來存放這些語句
| Binlog_stmt_cache_use | 4027 | //使用二進位制日誌快取檔案的非事物語句數量
| Bytes_received | 12624572922 |
| Bytes_sent | 38490032931 |
| Com_admin_commands | 1220886 |
| Com_assign_to_keycache | 0 |
| Com_alter_db | 0 |
| Com_alter_db_upgrade | 0 |
| Com_alter_event | 0 |
| Com_alter_function | 0 |
| Com_alter_procedure | 0 |
| Com_alter_server | 0 |
| Com_alter_table | 486 |
| Com_alter_tablespace | 0 |
| Com_alter_user | 0 |
| Com_analyze | 0 |
| Com_begin | 10954 |
| Com_binlog | 0 |
| Com_call_procedure | 0 |
| Com_change_db | 41989 |
| Com_change_master | 3 |
| Com_check | 0 |
| Com_checksum | 0 |
| Com_commit | 457143 |
| Com_create_db | 8 |
| Com_create_event | 0 |
| Com_create_function | 0 |
| Com_create_index | 0 |
| Com_create_procedure | 0 |
| Com_create_server | 0 |
| Com_create_table | 233 |
| Com_create_trigger | 3 |
| Com_create_udf | 0 |
| Com_create_user | 0 |
| Com_create_view | 0 |
| Com_dealloc_sql | 0 |
| Com_delete | 388 |
| Com_delete_multi | 0 |
| Com_do | 0 |
| Com_drop_db | 4 |
| Com_drop_event | 0 |
| Com_drop_function | 0 |
| Com_drop_index | 0 |
| Com_drop_procedure | 0 |
| Com_drop_server | 0 |
| Com_drop_table | 235 |
| Com_drop_trigger | 0 |
| Com_drop_user | 0 |
| Com_drop_view | 0 |
| Com_empty_query | 0 |
| Com_execute_sql | 0 |
| Com_flush | 5 |
| Com_get_diagnostics | 0 |
| Com_grant | 2 |
| Com_ha_close | 0 |
| Com_ha_open | 0 |
| Com_ha_read | 0 |
| Com_help | 0 |
| Com_insert | 549789 |
| Com_insert_select | 0 |
| Com_install_plugin | 0 |
| Com_kill | 0 |
| Com_load | 0 |
| Com_lock_tables | 231 |
| Com_optimize | 0 |
| Com_preload_keys | 0 |
| Com_prepare_sql | 0 |
| Com_purge | 0 |
| Com_purge_before_date | 0 |
| Com_release_savepoint | 0 |
| Com_rename_table | 0 |
| Com_rename_user | 0 |
| Com_repair | 0 |
| Com_replace | 59 |
| Com_replace_select | 0 |
| Com_reset | 4 |
| Com_resignal | 0 |
| Com_revoke | 0 |
| Com_revoke_all | 0 |
| Com_rollback | 404 |
| Com_rollback_to_savepoint | 0 |
| Com_savepoint | 0 |
| Com_select | 30597749 |
| Com_set_option | 18025324 |
| Com_signal | 0 |
| Com_show_binlog_events | 0 |
| Com_show_binlogs | 0 |
| Com_show_charsets | 11 |
| Com_show_collations | 11 |
| Com_show_create_db | 10 |
| Com_show_create_event | 0 |
| Com_show_create_func | 0 |
| Com_show_create_proc | 0 |
| Com_show_create_table | 3132 |
| Com_show_create_trigger | 3 |
| Com_show_databases | 72 |
| Com_show_engine_logs | 0 |
| Com_show_engine_mutex | 0 |
| Com_show_engine_status | 0 |
| Com_show_events | 0 |
| Com_show_errors | 0 |
| Com_show_fields | 10240 |
| Com_show_function_code | 0 |
| Com_show_function_status | 8 |
| Com_show_grants | 0 |
| Com_show_keys | 199 |
| Com_show_master_status | 156 |
| Com_show_open_tables | 0 |
| Com_show_plugins | 0 |
| Com_show_privileges | 0 |
| Com_show_procedure_code | 0 |
| Com_show_procedure_status | 8 |
| Com_show_processlist | 52 |
| Com_show_profile | 0 |
| Com_show_profiles | 0 |
| Com_show_relaylog_events | 0 |
| Com_show_slave_hosts | 0 |
| Com_show_slave_status | 123 |
| Com_show_status | 86 |
| Com_show_storage_engines | 29 |
| Com_show_table_status | 1160 |
| Com_show_tables | 158 |
| Com_show_triggers | 920 |
| Com_show_variables | 146 |
| Com_show_warnings | 0 |
| Com_slave_start | 4 |
| Com_slave_stop | 5 |
| Com_stmt_close | 25984 |
| Com_stmt_execute | 25984 |
| Com_stmt_fetch | 0 |
| Com_stmt_prepare | 25984 |
| Com_stmt_reprepare | 0 |
| Com_stmt_reset | 0 |
| Com_stmt_send_long_data | 0 |
| Com_truncate | 0 |
| Com_uninstall_plugin | 0 |
| Com_unlock_tables | 231 |
| Com_update | 549840 |
| Com_update_multi | 0 |
| Com_xa_commit | 0 |
| Com_xa_end | 0 |
| Com_xa_prepare | 0 |
| Com_xa_recover | 0 |
| Com_xa_rollback | 0 |
| Com_xa_start | 0 |
| Compression | OFF |
| Connection_errors_accept | 0 |
| Connection_errors_internal | 0 |
| Connection_errors_max_connections | 0 |
| Connection_errors_peer_address | 0 |
| Connection_errors_select | 0 |
| Connection_errors_tcpwrap | 0 |
| Connections | 17286940 |
| Created_tmp_disk_tables | 21299 | //伺服器執行語句時在硬碟上自動建立的臨時表的數量
| Created_tmp_files | 4983 | //伺服器執行語句時自動建立的記憶體中的臨時表的數量，如果Created_tmp_disk_tables引數大，可能要增加tmp_table_size值，使臨時表基於記憶體而不基於硬碟
Created_tmp_disk_tables / Created_tmp_tables * 100% <= 25% 比較好
| Created_tmp_tables | 146943 |
| Delayed_errors | 0 |
| Delayed_insert_threads | 0 |
| Delayed_writes | 0 |
| Flush_commands | 3 |
| Handler_commit | 33633280 |//內部提交語句數量
| Handler_delete | 450901 |
| Handler_discover | 0 |
| Handler_external_lock | 72477269 |
| Handler_mrr_init | 0 |
| Handler_prepare | 3052914 |
| Handler_read_first | 1218011 |
| Handler_read_key | 122750038676 |
| Handler_read_last | 304457 |
| Handler_read_next | 1836980702077 |
| Handler_read_prev | 54873155031 |
| Handler_read_rnd | 119396899834 |
| Handler_read_rnd_next | 55736189757 |
| Handler_rollback | 174 |
| Handler_savepoint | 0 |
| Handler_savepoint_rollback | 0 |
| Handler_update | 868882084 |
| Handler_write | 810135258 |
| Innodb_buffer_pool_dump_status | not started |
| Innodb_buffer_pool_load_status | not started |
| Innodb_buffer_pool_pages_data | 384599 |
| Innodb_buffer_pool_bytes_data | 6301270016 |
| Innodb_buffer_pool_pages_dirty | 1010 |
| Innodb_buffer_pool_bytes_dirty | 16547840 |
| Innodb_buffer_pool_pages_flushed | 1348133 |
| Innodb_buffer_pool_pages_free | 3085 |
| Innodb_buffer_pool_pages_misc | 5530 |
| Innodb_buffer_pool_pages_total | 393214 |
| Innodb_buffer_pool_read_ahead_rnd | 0 |
| Innodb_buffer_pool_read_ahead | 59653 |
| Innodb_buffer_pool_read_ahead_evicted | 0 |
| Innodb_buffer_pool_read_requests | 522476284584 |
| Innodb_buffer_pool_reads | 27587 |
| Innodb_buffer_pool_wait_free | 0 |//通過後臺向innodb快取池頁，
如果該值大於0，需要增加innodb_buffer_pool大小
| Innodb_buffer_pool_write_requests | 223185947 |
| Innodb_data_fsyncs | 1287541 |
| Innodb_data_pending_fsyncs | 0 |
| Innodb_data_pending_reads | 0 |
| Innodb_data_pending_writes | 0 |
| Innodb_data_read | 1475563520 |
| Innodb_data_reads | 90656 |
| Innodb_data_writes | 2483930 |
| Innodb_data_written | 53829655552 |
| Innodb_dblwr_pages_written | 1348133 |
| Innodb_dblwr_writes | 52495 |
| Innodb_have_atomic_builtins | ON |
| Innodb_log_waits | 0 |
//不為0，增加redo_log_buffer_size 的大小
| Innodb_log_write_requests | 20236030 |
| Innodb_log_writes | 1050665 |
| Innodb_os_log_fsyncs | 1061753 |
| Innodb_os_log_pending_fsyncs | 0 |
| Innodb_os_log_pending_writes | 0 |
| Innodb_os_log_written | 9647985152 |
| Innodb_page_size | 16384 |
| Innodb_pages_created | 402005 |
| Innodb_pages_read | 90056 |
| Innodb_pages_written | 1348133 |
| Innodb_row_lock_current_waits | 0 |
| Innodb_row_lock_time | 508 |
| Innodb_row_lock_time_avg | 127 |
| Innodb_row_lock_time_max | 220 |
| Innodb_row_lock_waits | 4 |
//當前等待行鎖的數量
| Innodb_rows_deleted | 450897 |
| Innodb_rows_inserted | 47670586 |
| Innodb_rows_read | 2067494266811 |
| Innodb_rows_updated | 559293 |
| Innodb_num_open_files | 262 |
| Innodb_truncated_status_writes | 0 |
| Innodb_available_undo_logs | 128 |
| Key_blocks_not_flushed | 0 |
| Key_blocks_unused | 0 |
| Key_blocks_used | 6698 |
| Key_read_requests | 1125072100 |
| Key_reads | 196951 |
| Key_write_requests | 294293748 |
| Key_writes | 1272202 |
| Last_query_cost | 0.000000 |
| Last_query_partial_plans | 0 |
| Max_used_connections | 115 |
| Not_flushed_delayed_rows | 0 |
| Open_files | 1310 |
| Open_streams | 0 |
| Open_table_definitions | 922 |
| Open_tables | 1084 | //當前開啟表數量
| Opened_files | 106007 |
| Opened_table_definitions | 2362 |
| Opened_tables | 2326 |//已經開啟表的數量，數值非常大，table_open_cache值太小，
| Performance_schema_accounts_lost | 0 |
| Performance_schema_cond_classes_lost | 0 |
| Performance_schema_cond_instances_lost | 0 |
| Performance_schema_digest_lost | 0 |
| Performance_schema_file_classes_lost | 0 |
| Performance_schema_file_handles_lost | 0 |
| Performance_schema_file_instances_lost | 0 |
| Performance_schema_hosts_lost | 0 |
| Performance_schema_locker_lost | 0 |
| Performance_schema_mutex_classes_lost | 0 |
| Performance_schema_mutex_instances_lost | 0 |
| Performance_schema_rwlock_classes_lost | 0 |
| Performance_schema_rwlock_instances_lost | 0 |
| Performance_schema_session_connect_attrs_lost | 0 |
| Performance_schema_socket_classes_lost | 0 |
| Performance_schema_socket_instances_lost | 0 |
| Performance_schema_stage_classes_lost | 0 |
| Performance_schema_statement_classes_lost | 0 |
| Performance_schema_table_handles_lost | 0 |
| Performance_schema_table_instances_lost | 0 |
| Performance_schema_thread_classes_lost | 0 |
| Performance_schema_thread_instances_lost | 0 |
| Performance_schema_users_lost | 0 |
| Prepared_stmt_count | 0 |
| Qcache_free_blocks | 1 |
| Qcache_free_memory | 1031352 |
| Qcache_hits | 0 |
| Qcache_inserts | 0 |
| Qcache_lowmem_prunes | 0 |
| Qcache_not_cached | 30592784 |
| Qcache_queries_in_cache | 0 |
| Qcache_total_blocks | 1 |
| Queries | 68742245 |
| Questions | 67444341 |
| Rpl_semi_sync_master_clients | 2 |
| Rpl_semi_sync_master_net_avg_wait_time | 16666 |
| Rpl_semi_sync_master_net_wait_time | 16396467002 |
| Rpl_semi_sync_master_net_waits | 983773 |
| Rpl_semi_sync_master_no_times | 1 |
| Rpl_semi_sync_master_no_tx | 72385 |
| Rpl_semi_sync_master_status | ON |
| Rpl_semi_sync_master_timefunc_failures | 0 |
| Rpl_semi_sync_master_tx_avg_wait_time | 971 |
| Rpl_semi_sync_master_tx_wait_time | 516125598 |
| Rpl_semi_sync_master_tx_waits | 531060 |
| Rpl_semi_sync_master_wait_pos_backtraverse | 0 |
| Rpl_semi_sync_master_wait_sessions | 0 |
| Rpl_semi_sync_master_yes_tx | 531163 |
| Select_full_join | 4643 |
| Select_full_range_join | 1531 |
| Select_range | 5638901 |
| Select_range_check | 0 |
| Select_scan | 1530785 |
| Slave_heartbeat_period