Wiki / Configuration Parameters
recovery_prefetch
Whether to try to prefetch blocks that are referenced in the WAL that are not yet in the buffer pool, during recovery. Valid values are off, on and try (the default). The setting try enables prefetching only if the operating system provides support for issuing read-ahead advice. Prefetching blocks that will soon be needed can reduce I/O wait times during recovery with some workloads. See also the wal_decode_buffer_size and maintenance_io_concurrency settings, which limit prefetching activity.
English manual coverage begins with PostgreSQL 7.4. Source history and runtime observations have their own recorded version boundaries.
Reading PG 18·Select a recorded version
- boot val
- try
- category
- Write-Ahead Log / Recovery
- context
- sighup
- documented
- true
- enumvals
- off, on, try
- extra desc
- Look ahead in the WAL to find references to uncached data.
- lang
- en
- max val
- Unknown
- metadata version
- 18
- min val
- Unknown
- name
- recovery_prefetch
- short desc
- Prefetch referenced blocks during recovery.
- source
- pg-settings-source-snapshot
- unit
- Unknown
- vartype
- enum
Definition PG 18
Whether to try to prefetch blocks that are referenced in the WAL that are not yet in the buffer pool, during recovery. Valid values are off, on and try (the default). The setting try enables prefetching only if the operating system provides support for issuing read-ahead advice. Prefetching blocks that will soon be needed can reduce I/O wait times during recovery with some workloads. See also the wal_decode_buffer_size and maintenance_io_concurrency settings, which limit prefetching activity.
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Definition sources
center · PostgreSQL 18 · wiki-repair-20261023:0e07b772b281e832941e0404bcf8999d5daadb156ad85ed545bfe29529c65705
Text language: en · wiki-repair-20261023:0e07b772b281e832941e0404bcf8999d5daadb156ad85ed545bfe29529c65705