Sleep between background-writer rounds.
At a glance
| Property | Value |
|---|---|
| Parameter | bgwriter_delay |
| Category | Background Writer |
| Default | 200ms |
| Value type | time (ms/s/min) |
| Change scope | Reload (no restart) |
What it does
Delay between activity rounds of the background writer, which proactively flushes dirty buffers so backends find clean ones.
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 bgwriter_delay; or SELECT name, setting, unit, context, source FROM pg_settings WHERE name = 'bgwriter_delay';.
Tuning guidance
Lower (50-100ms) with a higher bgwriter_lru_maxpages on write-heavy systems to reduce checkpoint spikes and backend-driven writes.