Re: CommitDelay performance improvement

> Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us> writes:
> > It could be tough. Imagine the delay increasing to 3 seconds? Seems
> > there has to be an upper bound on the sleep. The more you delay, the
> > more likely you will be to find someone to fsync you.
>
> Good point, and an excellent illustration of the fact that
> self-adjusting algorithms aren't that easy to get right the first
> time ;-)

I see. I am concerned that anything done to 7.1 at this point may cause
problems with performance under certain circumstances. Let's see what
the new code shows our testers.

>
> > Are we waking processes up after we have fsync()'ed them?
>
> Not at the moment. That would be another good mechanism to investigate
> for 7.2; but right now there's no infrastructure that would allow a
> backend to discover which other ones were sleeping for fsync.

Can we put the backends to sleep waiting for a lock, and have them wake
up later?

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