10bet网址
MySQL 5.7参考手册
相关的文档10bet官方网站 本手册下载 本手册节选

MySQL 5.7参考手册/MySQL性能模式/性能架构系统变量

25.15性能架构系统变量

性能模式实现了几个提供配置信息的系统变量:

mysql>显示变量为“perf%”;+----------------------------------------------------------+-------+ | Variable_name |值  | +----------------------------------------------------------+-------+ | 上performance_schema | | | performance_schema_accounts_size | 1 | | performance_schema_digests_size | 10000 | | performance_schema_events_stages_history_long_size | 10000 | | performance_schema_events_stages_history_size 10 | | | performance_schema_events_statements_history_long_size | 10000 | |performance_schema_events_statements_history_size 10 | | | performance_schema_events_transactions_history_long_size | 10000 | | performance_schema_events_transactions_history_size 10 | | | performance_schema_events_waits_history_long_size | 10000 | | performance_schema_events_waits_history_size 10 | | | performance_schema_hosts_size | 1 | | performance_schema_max_cond_classes | 80 | | performance_schema_max_cond_instances | 1 | | performance_schema_max_digest_length | 1024 | |performance_schema_max_file_classes 50 | | | performance_schema_max_file_handles | 32768 | | performance_schema_max_file_instances | 1 | | performance_schema_max_index_stat | 1 | | performance_schema_max_memory_classes | 320 | | performance_schema_max_metadata_locks | 1 | | performance_schema_max_mutex_classes | 200 | | performance_schema_max_mutex_instances | 1 | | performance_schema_max_prepared_statements_instances | 1 | | performance_schema_max_program_instances | 1 | |performance_schema_max_rwlock_classes 40 | | | performance_schema_max_rwlock_instances | 1 | | performance_schema_max_socket_classes 10 | | | performance_schema_max_socket_instances | 1 | | performance_schema_max_sql_text_length | 1024 | | performance_schema_max_stage_classes | 150 | | performance_schema_max_statement_classes | 192 | | performance_schema_max_statement_stack 10 | | | performance_schema_max_table_handles | 1 | | performance_schema_max_table_instances | 1 | |performance_schema_max_table_lock_stat | 1 | | performance_schema_max_thread_classes 50 | | | performance_schema_max_thread_instances | 1 | | performance_schema_session_connect_attrs_size | 512 | | performance_schema_setup_actors_size | 1 | | performance_schema_setup_objects_size | 1 | | performance_schema_users_size | 1  | +----------------------------------------------------------+-------+

性能架构系统变量可以在服务器启动时在命令行或选项文件中设置,许多变量可以在运行时设置。看到第25.13节“性能模式选项和变量参考”

如果在服务器启动时没有显式设置,Performance Schema会自动调整其几个参数的值。有关更多信息,请参见第25.3节,“性能模式启动配置”

Performance Schema系统变量含义如下: