mysql中my.cnf中常见的参数配置和解释

1.mysql中my.cnf常见参数的配置

1. [client]
   user=david
   password=88888888
   
   [mysqld]
   
   ########basic settings########
   
   server-id = 11 
   port = 3306
   user = mysql
   bind_address = 10.166.224.32   #根据实际情况修改
   autocommit = 0   #5.6.X安装时，需要注释掉，安装完成后再打开
   character_set_server=utf8mb4
   skip_name_resolve = 1
   max_connections = 800
   max_connect_errors = 1000
   datadir = /data/mysql_data      #根据实际情况修改,建议和程序分离存放
   transaction_isolation = READ-COMMITTED
   explicit_defaults_for_timestamp = 1
   join_buffer_size = 134217728
   tmp_table_size = 67108864
   tmpdir = /tmp
   max_allowed_packet = 16777216
   sql_mode = "STRICT_TRANS_TABLES,NO_ENGINE_SUBSTITUTION,NO_ZERO_DATE,NO_ZERO_IN_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER"
   interactive_timeout = 1800
   wait_timeout = 1800
   read_buffer_size = 16777216
   read_rnd_buffer_size = 33554432
   sort_buffer_size = 33554432
   
   ########log settings########
   
   log_error = error.log
   slow_query_log = 1
   slow_query_log_file = slow.log
   log_queries_not_using_indexes = 1
   log_slow_admin_statements = 1
   log_slow_slave_statements = 1
   log_throttle_queries_not_using_indexes = 10
   expire_logs_days = 90
   long_query_time = 2
   min_examined_row_limit = 100
   
   ########replication settings########
   
   master_info_repository = TABLE
   relay_log_info_repository = TABLE
   log_bin = bin.log
   sync_binlog = 1
   gtid_mode = on
   enforce_gtid_consistency = 1
   log_slave_updates
   binlog_format = row 
   relay_log = relay.log
   relay_log_recovery = 1
   binlog_gtid_simple_recovery = 1
   slave_skip_errors = ddl_exist_errors
   
   ########innodb settings########
   
   innodb_page_size = 8192
   innodb_buffer_pool_size = 6G    #根据实际情况修改
   innodb_buffer_pool_instances = 8
   innodb_buffer_pool_load_at_startup = 1
   innodb_buffer_pool_dump_at_shutdown = 1
   innodb_lru_scan_depth = 2000
   innodb_lock_wait_timeout = 5
   innodb_io_capacity = 4000
   innodb_io_capacity_max = 8000
   innodb_flush_method = O_DIRECT
   innodb_file_format = Barracuda
   innodb_file_format_max = Barracuda
   innodb_log_group_home_dir = /redolog/  #根据实际情况修改
   innodb_undo_directory = /undolog/      #根据实际情况修改
   innodb_undo_logs = 128
   innodb_undo_tablespaces = 3
   innodb_flush_neighbors = 1
   innodb_log_file_size = 4G               #根据实际情况修改
   innodb_log_buffer_size = 16777216
   innodb_purge_threads = 4
   innodb_large_prefix = 1
   innodb_thread_concurrency = 64
   innodb_print_all_deadlocks = 1
   innodb_strict_mode = 1
   innodb_sort_buffer_size = 67108864 
   
   ########semi sync replication settings########
   
   plugin_dir=/usr/local/mysql/lib/plugin      #根据实际情况修改
   plugin_load = "rpl_semi_sync_master=semisync_master.so;rpl_semi_sync_slave=semisync_slave.so"
   loose_rpl_semi_sync_master_enabled = 1
   loose_rpl_semi_sync_slave_enabled = 1
   loose_rpl_semi_sync_master_timeout = 5000
   
   [mysqld-5.7]
   innodb_buffer_pool_dump_pct = 40
   innodb_page_cleaners = 4
   innodb_undo_log_truncate = 1
   innodb_max_undo_log_size = 2G
   innodb_purge_rseg_truncate_frequency = 128
   binlog_gtid_simple_recovery=1
   log_timestamps=system
   transaction_write_set_extraction=MURMUR32
   show_compatibility_56=on
   

2. 几个重要的参数配置和说明

   • innodb_log_file_size = 4G :做实验可以更改的小点，线上环境推荐用4G，以前5.5和5.1等版本之所以官方给的值很小，是因为太大后有bug，现在bug已经修复

   • innodb_undo_logs = 128和innodb_undo_tablespaces = 3建议在安装之前就确定好该值，后续修改比较麻烦

   • [mysqld]，[mysqld-5.7]这种tag表明了下面的配置在什么版本下才生效,[mysqld]下均生效
   • autocommit,这个参数在5.5.X以后才有，安装5.6.X的时候要注意先把该参数注释掉，等安装完成后，再行打开, 5.7.X无需预先注释
   • datadir, innodb_log_group_home_dir, innodb_undo_directory一定要注意他的权限是 mysql:mysql