MySQL system variable 提供了 MySQL 服务器的常用配置项，为 MySQL 的日常问题诊断、排查、性能调优提供了非常灵活的选择，具体见官方文档：
https://dev.mysql.com/doc/refman/8.0/en/server-system-variables.html
| Variable_name | Value | scope | ||
|---|---|---|---|---|
| auto_increment_increment | 1 | |||
| auto_increment_offset | 1 | |||
| autocommit | ON | |||
| automatic_sp_privileges | ON | |||
| back_log | 2000 | |||
| basedir | /opt/udb/program/mysql/mysql-5.5.24 | |||
| big_tables | OFF | |||
| binlog_cache_size | 32768 | |||
| binlog_direct_non_transactional_updates | OFF | |||
| binlog_format | MIXED | |||
| binlog_stmt_cache_size | 32768 | |||
| bulk_insert_buffer_size | 8388608 | |||
| character_set_client | utf8 | |||
| character_set_connection | utf8 | |||
| character_set_database | utf8 | |||
| character_set_filesystem | binary | |||
| character_set_results | utf8 | |||
| character_set_server | utf8 | |||
| character_set_system | utf8 | |||
| character_sets_dir | /opt/udb/program/mysql/mysql-5.5.24/share/charsets/ | |||
| collation_connection | utf8_general_ci | |||
| collation_database | utf8_general_ci | |||
| collation_server | utf8_general_ci | |||
| completion_type | NO_CHAIN | |||
| concurrent_insert | AUTO | |||
| connect_timeout | 10 | |||
| datadir | /opt/udb/instance/mysql-5.5/udb-ovzdmx/data/ | |||
| date_format | %Y-%m-%d | |||
| datetime_format | %Y-%m-%d %H:%i:%s | |||
| default_storage_engine | InnoDB | |||
| default_week_format | 0 | |||
| delay_key_write | ON | |||
| delayed_insert_limit | 100 | |||
| delayed_insert_timeout | 300 | |||
| delayed_queue_size | 1000 | |||
| div_precision_increment | 4 | |||
| engine_condition_pushdown | ON | |||
| error_count | 0 | |||
| event_scheduler | OFF | |||
| expire_logs_days | 7 | |||
| external_user | ||||
| flush | OFF | |||
| flush_time | 0 | |||
| foreign_key_checks | ON | |||
| ft_boolean_syntax | + -><()~*:”&\ | |||
| ft_max_word_len | 84 | |||
| ft_min_word_len | 4 | |||
| ft_query_expansion_limit | 20 | |||
| ft_stopword_file | (built-in) | |||
| general_log | OFF | |||
| general_log_file | /opt/udb/instance/mysql-5.5/udb-ovzdmx/log/mysqld.log | |||
| group_concat_max_len | 51200 | |||
| have_compress | YES | |||
| have_crypt | YES | |||
| have_csv | YES | |||
| have_dynamic_loading | YES | |||
| have_geometry | YES | |||
| have_innodb | YES | |||
| have_ndbcluster | NO | |||
| have_openssl | NO | |||
| have_partitioning | YES | |||
| have_profiling | YES | |||
| have_query_cache | YES | |||
| have_rtree_keys | YES | |||
| have_ssl | NO | |||
| have_symlink | YES | |||
| hostname | 046c68c53211 | |||
| identity | 0 | |||
| ignore_builtin_innodb | OFF | |||
| init_connect | ||||
| init_file | ||||
| init_slave | ||||
| innodb_adaptive_flushing | ON | |||
| innodb_adaptive_hash_index | ON | |||
| innodb_additional_mem_pool_size | 8388608 | |||
| innodb_autoextend_increment | 8 | |||
| innodb_autoinc_lock_mode | 1 | |||
| innodb_buffer_pool_instances | 1 | |||
| innodb_buffer_pool_size | 1887436800 | |||
| innodb_change_buffering | all | |||
| innodb_checksums | ON | |||
| innodb_commit_concurrency | 0 | |||
| innodb_concurrency_tickets | 500 | |||
| innodb_data_file_path | ibdata1:100M:autoextend | |||
| innodb_data_home_dir | /opt/udb/instance/mysql-5.5/udb-ovzdmx/data | |||
| innodb_doublewrite | ON | |||
| innodb_fast_shutdown | 1 | |||
| innodb_file_format | Antelope | |||
| innodb_file_format_check | ON | |||
| innodb_file_format_max | Antelope | |||
| innodb_file_per_table | ON | |||
| innodb_flush_log_at_trx_commit | 2 | |||
| innodb_flush_method | O_DIRECT | |||
| innodb_force_load_corrupted | OFF | |||
| innodb_force_recovery | 0 | |||
| innodb_io_capacity | 2000 | |||
| innodb_large_prefix | OFF | |||
| innodb_lock_wait_timeout | 50 | |||
| innodb_locks_unsafe_for_binlog | OFF | |||
| innodb_log_buffer_size | 8388608 | |||
| innodb_log_file_size | 536870912 | |||
| innodb_log_files_in_group | 2 | |||
| innodb_log_group_home_dir | /opt/udb/instance/mysql-5.5/udb-ovzdmx/data | |||
| innodb_max_dirty_pages_pct | 50 | |||
| innodb_max_purge_lag | 0 | |||
| innodb_mirrored_log_groups | 1 | |||
| innodb_old_blocks_pct | 37 | |||
| innodb_old_blocks_time | 0 | |||
| innodb_open_files | 1024 | |||
| innodb_purge_batch_size | 20 | |||
| innodb_purge_threads | 0 | |||
| innodb_random_read_ahead | OFF | |||
| innodb_read_ahead_threshold | 56 | |||
| innodb_read_io_threads | 8 | |||
| innodb_replication_delay | 0 | |||
| innodb_rollback_on_timeout | OFF | |||
| innodb_rollback_segments | 128 | |||
| innodb_spin_wait_delay | 6 | |||
| innodb_stats_method | nulls_equal | |||
| innodb_stats_on_metadata | ON | |||
| innodb_stats_sample_pages | 8 | |||
| innodb_strict_mode | OFF | |||
| innodb_support_xa | ON | |||
| innodb_sync_spin_loops | 30 | |||
| innodb_table_locks | ON | |||
| innodb_thread_concurrency | 20 | |||
| innodb_thread_sleep_delay | 10000 | |||
| innodb_use_native_aio | ON | |||
| innodb_use_sys_malloc | ON | |||
| innodb_version | 1.1.8 | |||
| innodb_write_io_threads | 8 | |||
| insert_id | 0 | |||
| interactive_timeout | 28800 | |||
| join_buffer_size | 131072 | |||
| keep_files_on_create | OFF | |||
| key_buffer_size | 33554432 | |||
| key_cache_age_threshold | 300 | |||
| key_cache_block_size | 1024 | |||
| key_cache_division_limit | 100 | |||
| large_files_support | ON | |||
| large_page_size | 0 | |||
| large_pages | OFF | |||
| last_insert_id | 0 | |||
| lc_messages | en_US | |||
| lc_messages_dir | /opt/udb/program/mysql/mysql-5.5.24/share/ | |||
| lc_time_names | en_US | |||
| license | GPL | |||
| local_infile | ON | |||
| lock_wait_timeout | 31536000 | |||
| locked_in_memory | OFF | |||
| log | OFF | |||
| log_bin | ON | |||
| log_bin_trust_function_creators | ON | |||
| log_error | /opt/udb/instance/mysql-5.5/udb-ovzdmx/log/mysqld.log | |||
| log_output | TABLE | |||
| log_queries_not_using_indexes | OFF | |||
| log_slave_updates | OFF | |||
| log_slow_queries | ON | |||
| log_warnings | 1 | |||
| long_query_time | 3 | |||
| low_priority_updates | OFF | |||
| lower_case_file_system | OFF | |||
| lower_case_table_names | 0 | |||
| max_allowed_packet | 16777216 | |||
| max_binlog_cache_size | 18446744073709547520 | |||
| max_binlog_size | 1073741824 | |||
| max_binlog_stmt_cache_size | 18446744073709547520 | |||
| max_connect_errors | 1000000 | |||
| max_connections | 2000 | |||
| max_delayed_threads | 20 | |||
| max_error_count | 64 | |||
| max_heap_table_size | 16777216 | |||
| max_insert_delayed_threads | 20 | |||
| max_join_size | 18446744073709551615 | |||
| max_length_for_sort_data | 1024 | |||
| max_long_data_size | 16777216 | |||
| max_prepared_stmt_count | 16382 | |||
| max_relay_log_size | 0 | |||
| max_seeks_for_key | 18446744073709551615 | |||
| max_sort_length | 1024 | |||
| max_sp_recursion_depth | 0 | |||
| max_tmp_tables | 32 | |||
| max_user_connections | 0 | |||
| max_write_lock_count | 18446744073709551615 | |||
| metadata_locks_cache_size | 1024 | |||
| min_examined_row_limit | 0 | |||
| multi_range_count | 256 | |||
| myisam_data_pointer_size | 6 | |||
| myisam_max_sort_file_size | 9223372036853727232 | |||
| myisam_mmap_size | 18446744073709551615 | |||
| myisam_recover_options | OFF | |||
| myisam_repair_threads | 1 | |||
| myisam_sort_buffer_size | 8388608 | |||
| myisam_stats_method | nulls_unequal | |||
| myisam_use_mmap | OFF | |||
| net_buffer_length | 8192 | |||
| net_read_timeout | 30 | |||
| net_retry_count | 10 | |||
| net_write_timeout | 60 | |||
| new | OFF | |||
| old | OFF | |||
| old_alter_table | OFF | |||
| old_passwords | OFF | |||
| open_files_limit | 150000 | |||
| optimizer_prune_level | 1 | |||
| optimizer_search_depth | 62 | |||
| optimizer_switch | index_merge=on,index_merge_union=on,index_merge_sort_union=on,index_merge_intersection=on,engine_condition_pushdown=on | |||
| performance_schema | OFF | |||
| performance_schema_events_waits_history_long_size | 10000 | |||
| performance_schema_events_waits_history_size | 10 | |||
| performance_schema_max_cond_classes | 80 | |||
| performance_schema_max_cond_instances | 1000 | |||
| performance_schema_max_file_classes | 50 | |||
| performance_schema_max_file_handles | 32768 | |||
| performance_schema_max_file_instances | 10000 | |||
| performance_schema_max_mutex_classes | 200 | |||
| performance_schema_max_mutex_instances | 1000000 | |||
| performance_schema_max_rwlock_classes | 30 | |||
| performance_schema_max_rwlock_instances | 1000000 | |||
| performance_schema_max_table_handles | 100000 | |||
| performance_schema_max_table_instances | 50000 | |||
| performance_schema_max_thread_classes | 50 | |||
| performance_schema_max_thread_instances | 1000 | |||
| pid_file | /opt/udb/instance/mysql-5.5/udb-ovzdmx/mysqld.pid | |||
| plugin_dir | /opt/udb/program/mysql/mysql-5.5.24/lib/plugin/ | |||
| port | 3306 | |||
| preload_buffer_size | 32768 | |||
| profiling | OFF | |||
| profiling_history_size | 15 | |||
| protocol_version | 10 | |||
| proxy_user | ||||
| pseudo_thread_id | 111080103 | |||
| query_alloc_block_size | 8192 | |||
| query_cache_limit | 1048576 | |||
| query_cache_min_res_unit | 4096 | |||
| query_cache_size | 0 | |||
| query_cache_type | OFF | |||
| query_cache_wlock_invalidate | OFF | |||
| query_prealloc_size | 8192 | |||
| rand_seed1 | 0 | |||
| rand_seed2 | 0 | |||
| range_alloc_block_size | 4096 | |||
| read_buffer_size | 262144 | |||
| read_only | ON | |||
| read_rnd_buffer_size | 524288 | |||
| relay_log | /opt/udb/instance/mysql-5.5/udb-ovzdmx/relaylog/mysql-relay.log | |||
| relay_log_index | ||||
| relay_log_info_file | relay-log.info | |||
| relay_log_purge | ON | |||
| relay_log_recovery | OFF | |||
| relay_log_space_limit | 0 | |||
| report_host | ||||
| report_password | ||||
| report_port | 3306 | |||
| report_user | ||||
| rpl_recovery_rank | 0 | |||
| rpl_semi_sync_master_enabled | OFF | |||
| rpl_semi_sync_master_timeout | 10000 | |||
| rpl_semi_sync_master_trace_level | 32 | |||
| rpl_semi_sync_master_wait_no_slave | ON | |||
| rpl_semi_sync_slave_enabled | OFF | |||
| rpl_semi_sync_slave_trace_level | 32 | |||
| secure_auth | OFF | |||
| secure_file_priv | /opt/udb/instance/mysql-5.5/udb-ovzdmx/tmp/ | |||
| server_id | 168430248 | |||
| skip_external_locking | ON | |||
| skip_name_resolve | ON | |||
| skip_networking | OFF | |||
| skip_show_database | OFF | |||
| slave_compressed_protocol | OFF | |||
| slave_exec_mode | STRICT | |||
| slave_load_tmpdir | /opt/udb/instance/mysql-5.5/udb-ovzdmx/tmp | |||
| slave_net_timeout | 3600 | |||
| slave_skip_errors | OFF | |||
| slave_transaction_retries | 10 | |||
| slave_type_conversions | ||||
| slow_launch_time | 2 | |||
| slow_query_log | ON | |||
| slow_query_log_file | /opt/udb/instance/mysql-5.5/udb-ovzdmx/log/mysql-slow.log | |||
| socket | /opt/udb/instance/mysql-5.5/udb-ovzdmx/mysqld.sock | |||
| sort_buffer_size | 524288 | |||
| sql_auto_is_null | OFF | |||
| sql_big_selects | ON | |||
| sql_big_tables | OFF | |||
| sql_buffer_result | OFF | |||
| sql_log_bin | ON | |||
| sql_log_off | OFF | |||
| sql_low_priority_updates | OFF | |||
| sql_max_join_size | 18446744073709551615 | |||
| sql_mode | ||||
| sql_notes | ON | |||
| sql_quote_show_create | ON | |||
| sql_safe_updates | OFF | |||
| sql_select_limit | 18446744073709551615 | |||
| sql_slave_skip_counter | 0 | |||
| sql_warnings | OFF | |||
| ssl_ca | ||||
| ssl_capath | ||||
| ssl_cert | ||||
| ssl_cipher | ||||
| ssl_key | ||||
| storage_engine | InnoDB | |||
| stored_program_cache | 256 | |||
| sync_binlog | 1 | |||
| sync_frm | ON | |||
| sync_master_info | 0 | |||
| sync_relay_log | 0 | |||
| sync_relay_log_info | 0 | |||
| system_time_zone | CST | |||
| table_definition_cache | 400 | |||
| table_open_cache | 128 | |||
| thread_cache_size | 50 | |||
| thread_concurrency | 10 | |||
| thread_handling | one-thread-per-connection | |||
| thread_stack | 262144 | |||
| time_format | %H:%i:%s | |||
| time_zone | SYSTEM | |||
| timed_mutexes | OFF | |||
| timestamp | 1524477955 | |||
| tmp_table_size | 16777216 | |||
| tmpdir | /opt/udb/instance/mysql-5.5/udb-ovzdmx/tmp | |||
| transaction_alloc_block_size | 8192 | |||
| transaction_prealloc_size | 4096 | |||
| tx_isolation | REPEATABLE-READ | |||
| unique_checks | ON | |||
| updatable_views_with_limit | YES | |||
| version | 5.5.24-ucloudrel1-log | |||
| version_comment | Source distribution | |||
| version_compile_machine | x86_64 | |||
| version_compile_os | Linux | |||
| wait_timeout | 28800 | Both | mysql 在关闭一个不活动 connection 之前等待的秒数 | |
| warning_count | 0 |
