当许多查询同时执行时,InnoDB缓冲池是一个众所周知的争用点。在XtraDB中,保护缓冲池的全局互斥体已经被分成几个互斥体来减少争用。
该功能将单个全局InnoDB缓冲池互斥体分为几个互斥体:
Name |
Protects |
Flush_state_mutex |
flushing state of dirty blocks |
LRU_list_mutex |
LRU lists of blocks in buffer pool |
Flush_list_mutex |
flush list of dirty blocks to flush |
Free_list_mutex |
list of free blocks in buffer pool |
Zip_free_mutex |
lists of free area to treat compressed pages |
Zip_hash_mutex |
hash table to search compressed pages |
此更改的目的是减少互斥量争用,当内存中的工作集不适合,这将会非常有影响。