Write full page images after a checkpoint to survive torn pages.
At a glance
| Property | Value |
|---|---|
| Parameter | full_page_writes |
| Category | WAL |
| Default | on |
| Value type | boolean / enum / numeric |
| Change scope | Reload (no restart) |
What it does
When on, the first modification to a page after each checkpoint writes the entire page to WAL, protecting against partial (torn) page writes during a crash.
How to apply a change
Takes effect on configuration reload (sighup context). Run SELECT pg_reload_conf(); or send SIGHUP — no restart needed.
Inspect the current value and source with SHOW full_page_writes; or SELECT name, setting, unit, context, source FROM pg_settings WHERE name = 'full_page_writes';.
Tuning guidance
Keep on unless your storage guarantees atomic page writes. Turning it off risks corruption; it inflates WAL volume just after checkpoints.