Information Schema INNODB_BUFFER_POOL_STATS Table

The Information Schema INNODB_BUFFER_POOL_STATS table contains information about pages in the buffer pool, similar to what is returned with the SHOW ENGINE INNODB STATUS statement.

The PROCESS privilege is required to view the table.

It has the following columns:

Column	Description
`POOL_ID`	Buffer Pool identifier. From MariaDB 10.5.1 returns a value of 0, since multiple InnoDB buffer pool instances has been removed.
`POOL_SIZE`	Size in pages of the buffer pool.
`FREE_BUFFERS`	Number of free pages in the buffer pool.
`DATABASE_PAGES`	Total number of pages in the buffer pool.
`OLD_DATABASE_PAGES`	Number of pages in the old sublist.
`MODIFIED_DATABASE_PAGES`	Number of dirty pages.
`PENDING_DECOMPRESS`	Number of pages pending decompression.
`PENDING_READS`	Pending buffer pool level reads.
`PENDING_FLUSH_LRU`	Number of pages in the LRU pending flush.
`PENDING_FLUSH_LIST`	Number of pages in the flush list pending flush.
`PAGES_MADE_YOUNG`	Pages moved from the old sublist to the new sublist.
`PAGES_NOT_MADE_YOUNG`	Pages that have remained in the old sublist without moving to the new sublist.
`PAGES_MADE_YOUNG_RATE`	Hits that cause blocks to move to the top of the new sublist.
`PAGES_MADE_NOT_YOUNG_RATE`	Hits that do not cause blocks to move to the top of the new sublist due to the `innodb_old_blocks` delay not being met.
`NUMBER_PAGES_READ`	Number of pages read.
`NUMBER_PAGES_CREATED`	Number of pages created.
`NUMBER_PAGES_WRITTEN`	Number of pages written.
`PAGES_READ_RATE`	Number of pages read since the last printout divided by the time elapsed, giving pages read per second.
`PAGES_CREATE_RATE`	Number of pages created since the last printout divided by the time elapsed, giving pages created per second.
`PAGES_WRITTEN_RATE`	Number of pages written since the last printout divided by the time elapsed, giving pages written per second.
`NUMBER_PAGES_GET`	Number of logical read requests.
`HIT_RATE`	Buffer pool hit rate.
`YOUNG_MAKE_PER_THOUSAND_GETS`	For every 1000 gets, the number of pages made young.
`NOT_YOUNG_MAKE_PER_THOUSAND_GETS`	For every 1000 gets, the number of pages not made young.
`NUMBER_PAGES_READ_AHEAD`	Number of pages read ahead.
`NUMBER_READ_AHEAD_EVICTED`	Number of pages read ahead by the read-ahead thread that were later evicted without being accessed by any queries.
`READ_AHEAD_RATE`	Pages read ahead since the last printout divided by the time elapsed, giving read-ahead rate per second.
`READ_AHEAD_EVICTED_RATE`	Read-ahead pages not accessed since the last printout divided by time elapsed, giving the number of read-ahead pages evicted without access per second.
`LRU_IO_TOTAL`	Total least-recently used I/O.
`LRU_IO_CURRENT`	Least-recently used I/O for the current interval.
`UNCOMPRESS_TOTAL`	Total number of pages decompressed.
`UNCOMPRESS_CURRENT`	Number of pages decompressed in the current interval

Examples

DESC information_schema.innodb_buffer_pool_stats;
+----------------------------------+---------------------+------+-----+---------+-------+
| Field                            | Type                | Null | Key | Default | Extra |
+----------------------------------+---------------------+------+-----+---------+-------+
| POOL_ID                          | bigint(21) unsigned | NO   |     | 0       |       |
| POOL_SIZE                        | bigint(21) unsigned | NO   |     | 0       |       |
| FREE_BUFFERS                     | bigint(21) unsigned | NO   |     | 0       |       |
| DATABASE_PAGES                   | bigint(21) unsigned | NO   |     | 0       |       |
| OLD_DATABASE_PAGES               | bigint(21) unsigned | NO   |     | 0       |       |
| MODIFIED_DATABASE_PAGES          | bigint(21) unsigned | NO   |     | 0       |       |
| PENDING_DECOMPRESS               | bigint(21) unsigned | NO   |     | 0       |       |
| PENDING_READS                    | bigint(21) unsigned | NO   |     | 0       |       |
| PENDING_FLUSH_LRU                | bigint(21) unsigned | NO   |     | 0       |       |
| PENDING_FLUSH_LIST               | bigint(21) unsigned | NO   |     | 0       |       |
| PAGES_MADE_YOUNG                 | bigint(21) unsigned | NO   |     | 0       |       |
| PAGES_NOT_MADE_YOUNG             | bigint(21) unsigned | NO   |     | 0       |       |
| PAGES_MADE_YOUNG_RATE            | double              | NO   |     | 0       |       |
| PAGES_MADE_NOT_YOUNG_RATE        | double              | NO   |     | 0       |       |
| NUMBER_PAGES_READ                | bigint(21) unsigned | NO   |     | 0       |       |
| NUMBER_PAGES_CREATED             | bigint(21) unsigned | NO   |     | 0       |       |
| NUMBER_PAGES_WRITTEN             | bigint(21) unsigned | NO   |     | 0       |       |
| PAGES_READ_RATE                  | double              | NO   |     | 0       |       |
| PAGES_CREATE_RATE                | double              | NO   |     | 0       |       |
| PAGES_WRITTEN_RATE               | double              | NO   |     | 0       |       |
| NUMBER_PAGES_GET                 | bigint(21) unsigned | NO   |     | 0       |       |
| HIT_RATE                         | bigint(21) unsigned | NO   |     | 0       |       |
| YOUNG_MAKE_PER_THOUSAND_GETS     | bigint(21) unsigned | NO   |     | 0       |       |
| NOT_YOUNG_MAKE_PER_THOUSAND_GETS | bigint(21) unsigned | NO   |     | 0       |       |
| NUMBER_PAGES_READ_AHEAD          | bigint(21) unsigned | NO   |     | 0       |       |
| NUMBER_READ_AHEAD_EVICTED        | bigint(21) unsigned | NO   |     | 0       |       |
| READ_AHEAD_RATE                  | double              | NO   |     | 0       |       |
| READ_AHEAD_EVICTED_RATE          | double              | NO   |     | 0       |       |
| LRU_IO_TOTAL                     | bigint(21) unsigned | NO   |     | 0       |       |
| LRU_IO_CURRENT                   | bigint(21) unsigned | NO   |     | 0       |       |
| UNCOMPRESS_TOTAL                 | bigint(21) unsigned | NO   |     | 0       |       |
| UNCOMPRESS_CURRENT               | bigint(21) unsigned | NO   |     | 0       |       |
+----------------------------------+---------------------+------+-----+---------+-------+

Content reproduced on this site is the property of its respective owners, and this content is not reviewed in advance by MariaDB. The views, information and opinions expressed by this content do not necessarily represent those of MariaDB or any other party.

© 2021 MariaDB
Licensed under the Creative Commons Attribution 3.0 Unported License and the GNU Free Documentation License.
https://mariadb.com/kb/en/information-schema-innodb_buffer_pool_stats-table/