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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 ID of the buffer pool instance.
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       |       |
+----------------------------------+---------------------+------+-----+---------+-------+
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https://mariadb.com/kb/en/information-schema-innodb_buffer_pool_stats-table/