Re: Group Commit

> On Mon, 9 Apr 2007, Bruce Momjian wrote:
>
> > The big question is who is going to care about the milliseconds delay
> > and is using a configuration that is going to benefit from commit_delay.
>
> I care. WAL writes are a major bottleneck when many clients are
> committing near the same time. Both times I've played with the
> commit_delay settings I found it improved the peak throughput under load
> at an acceptable low cost in latency. I'll try to present some numbers on
> that when I get time, before you make me cry by taking it away.

Totally agreed here. I experienced throughput improvement by using
commit_delay too.

> An alternate mechanism that tells the client the commit is done when it
> hasn't hit disk is of no use for the applications I work with, so I
> haven't even been paying attention to no-commit-wait.

Agreed too.
--
Tatsuo Ishii
SRA OSS, Inc. Japan