STATISTICS VIEW · Statistics view

pg_stat_slru

PostgreSQL documentation ↗Source definition ↗

PostgreSQL accesses certain on-disk information via SLRU (simple least-recently-used) caches. The pg_stat_slru view will contain one row for each tracked SLRU cache, showing statistics about access to cached pages. For each SLRU cache that's part of the core server, there is a configuration parameter that controls its size, with the suffix _buffers appended.

First seen PG 13Last seen PG 19Columns 9

9.0 9.1 9.2 9.3 9.4 9.5 9.6 10 11 12 13 14 15 16 17 18 19^β3

Checked column by column against a PostgreSQL 18.6 instance · Raw measurement record ↗

Columns PostgreSQL 18

pg_stat_slru

COLUMN	TYPE	DESCRIPTION
`name`	`text`	Name of the SLRU
`blks_zeroed`	`bigint`	Number of blocks zeroed during initializations
`blks_hit`	`bigint`	Number of times disk blocks were found already in the SLRU, so that a read was not necessary (this only includes hits in the SLRU, not the operating system's file system cache)
`blks_read`	`bigint`	Number of disk blocks read for this SLRU
`blks_written`	`bigint`	Number of disk blocks written for this SLRU
`blks_exists`	`bigint`	Number of blocks checked for existence for this SLRU
`flushes`	`bigint`	Number of flushes of dirty data for this SLRU
`truncates`	`bigint`	Number of truncates for this SLRU
`stats_reset`	`timestamp with time zone`	Time at which these statistics were last reset

Columns marked "implicit" are not included in SELECT *; some early statistics views are completed from same-version source, and the extra provenance is shown in the column description.

Column evolution matrix

Hover a cell for the column type

PresentAdded / type or attribute changeRemoved

COLUMN	9.0	9.1	9.2	9.3	9.4	9.5	9.6	10	11	12
`name`	–	–	–	–	–	–	–	–	–	–
`blks_zeroed`	–	–	–	–	–	–	–	–	–	–
`blks_hit`	–	–	–	–	–	–	–	–	–	–
`blks_read`	–	–	–	–	–	–	–	–	–	–
`blks_written`	–	–	–	–	–	–	–	–	–	–
`blks_exists`	–	–	–	–	–	–	–	–	–	–
`flushes`	–	–	–	–	–	–	–	–	–	–
`truncates`	–	–	–	–	–	–	–	–	–	–
`stats_reset`	–	–	–	–	–	–	–	–	–	–

9.0 is the coverage baseline; a column already present in the baseline is not marked as added. The matrix aligns columns by name, so a rename appears as the old column removed and a new column added.

Evolution timeline

Changes between adjacent majors

PostgreSQL 17 ← 16

Catalog description updated

PostgreSQL 13 ← 12Catalog added

+ name+ blks_zeroed+ blks_hit+ blks_read+ blks_written+ blks_exists+ flushes+ truncates+ stats_reset

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