Re: postgresql latency & bgwriter not doing its job

On 2014-08-27 11:05:52 +0200, Fabien COELHO wrote:
> I can test a couple of patches. I already did one on someone advice (make
> bgwriter round all stuff in 1s instead of 120s, without positive effect.

I've quickly cobbled together the attached patch (which at least doesn't
seem to crash & burn). It tries to trigger pages being flushed out
during the paced phase of checkpoints instead of the fsync phase. The
sync_on_checkpoint_flush can be used to enable/disable that behaviour.

I'd be interested to hear whether that improves your latency numbers. I
unfortunately don't have more time to spend on this right now :(.

Greetings,

Andres Freund

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