InnoDB in MySQL_ page_ Cleaners details

innodb_page_cleaners yes MySQL Number of dirty threads in , Its value is equal to innodb_buffer_pool_instances Value , If innodb_page_cleaners The value is greater than innodb_buffer_pool_instances Value , Then automatically innodb_page_cleaners Adjust to and innodb_buffer_pool_instances The value of is the same , No adjustment shall be made in other cases .

The default values are 1, Here's the picture ：

[test]> select @@innodb_page_cleaners;
+------------------------+
| @@innodb_page_cleaners |
+------------------------+
|                      1 |
+------------------------+

[test]> select @@innodb_buffer_pool_instances;
+--------------------------------+
| @@innodb_buffer_pool_instances |
+--------------------------------+
|                              1 |
+--------------------------------+

innodb_page_cleaners Is a coordination thread + One or more task Composed of threads . If innodb_page_cleaners=1, Then it is the coordination thread itself , Another worker thread .

innodb_buffer_pool_instances The default value of is 1.innodb_buffer_pool_instances It means to be innodb buffer pool How many areas are divided , The number of areas is innodb_buffer_pool_instances Value . The purpose is to facilitate management and reduce the granularity of locks , Improve concurrency .

If there is a mistake , Please contact me by email ：[email protected]