Re: checkpoint_timeout

Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us> writes:

> I don't see something that happens every five minutes as any kind of
> performance problem. I am not sure what Josh saw that made him want to
> increase that.

I would have thought checkpoint_timeout would be something you would adjust
depending on whether you want even performance (set it low and live with
redundant i/o) or maximum throughput (set it high and live with i/o spikes and
performance dropouts). Does that make sense?

I suspect the origin of this meme might be with those benchmark graphs that
were being posted here that had the checkpoint timeout set to 30m. That seems
to be a bogus setting that's just hiding some of the i/o by postponing it
until after the test ends.

--
greg