mysql服务器内存使用情况总结

活动链接（动态）使用的内存数量如下所示：

per_connection_memory =

read_buffer_size //memory for sequential table scans

+read_rnd_buffer_size // memory for buffering reads

+sort_buffer_size // memory ofr in mem sorts

+thread_stack //per connection memory

+join_buffer_size // memory for in mem table joins

每台服务器（固定）使用内存的数量如下所示：

per_server_memory =

tmp_table_size //memory for all temp tables

+max_heap_table_size // max size of single temp table

+key_buffer_size //memory allocated for index blocks

+innodb_buffer_pool_size // main cache for InnoDB data

+innodb_additional_mem_pool_size // InnoDB record structure cache

+innodb_log_buffer_size // log file write buffer

+query_cache_size // compiled statement cache

Mysql可以使用的最大内存定义如下：

max_memory = (per_connection_memory* max _connections) + per_server_memory