20.30.18. The `INFORMATION_SCHEMA INNODB_BUFFER_POOL_STATS` Table

The INNODB_BUFFER_POOL_STATS table represents the same kinds of InnoDB buffer pool information as the output from SHOW ENGINE INNODB STATUS.

The idea of making pages in the buffer pool "young" or "not young" refers to transferring them between the sublists at the head and tail of the buffer pool data structure. Pages made "young" take longer to age out of the buffer pool, while pages made "not young" are moved much closer to the point of eviction.

Column meanings in this table are intended to be self-explanatory for developers who formerly parsed the SHOW ENGINE INNODB STATUS to get these values.

Table 20.17. INNODB_BUFFER_POOL_STATS Columns

Column name	Description
`POOL_ID`
`POOL_SIZE`
`FREE_BUFFERS`
`DATABASE_PAGES`
`OLD_DATABASE_PAGES`
`MODIFIED_DATABASE_PAGES`
`PENDING_DECOMPRESS`
`PENDING_READS`
`PENDING_FLUSH_LRU`
`PENDING_FLUSH_LIST`
`PAGES_MADE_YOUNG`
`PAGES_NOT_MADE_YOUNG`
`PAGES_MADE_YOUNG_RATE`
`PAGES_MADE_NOT_YOUNG_RATE`
`NUMBER_PAGES_READ`
`NUMBER_PAGES_CREATED`
`NUMBER_PAGES_WRITTEN`
`PAGES_READ_RATE`
`PAGES_CREATE_RATE`
`PAGES_WRITTEN_RATE`
`NUMBER_PAGES_GET`
`HIT_RATE`
`YOUNG_MAKE_PER_THOUSAND_GETS`
`NOT_YOUNG_MAKE_PER_THOUSAND_GETS`
`NUMBER_PAGES_READ_AHEAD`
`NUMBER_READ_AHEAD_EVICTED`
`READ_AHEAD_RATE`
`REAT_AHEAD_EVICTED_RATE`
`LRU_IO_TOTAL`
`LRU_IO_CURRENT`
`UNCOMPRESS_TOTAL`
`UNCOMPRESS_CURRENT`

Notes:

This table is primarily useful for expert-level performance monitoring, or when developing performance-related extensions for MySQL.
Since the INFORMATION_SCHEMA is a general-purpose way to monitor the MySQL server, use this table rather than the corresponding InnoDB system table for any new monitoring application you develop.
You must have the PROCESS privilege to query this table.

20.30.18. The INFORMATION_SCHEMA INNODB_BUFFER_POOL_STATS Table

20.30.18. The `INFORMATION_SCHEMA INNODB_BUFFER_POOL_STATS` Table