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 | |
+----------------------------------+---------------------+------+-----+---------+-------+
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