Re: Latch for the WAL writer - further reducing idle wake-ups.

On Thu, May 3, 2012 at 2:41 AM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
> On Wed, May 2, 2012 at 7:21 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> It is getting a bit late to be considering such changes for 9.2, but
>> I'm willing to review and commit this if there's not anybody who feels
>> strongly that it's too late.  Personally I think it's in the nature of
>> cleanup and so fair game as long as we haven't formally started beta.
>> However I will confess to some bias about wanting to get the server's
>> idle wake-up rate down, because Fedora people have been bugging me
>> about that for a long time now.  So I'm probably not the best person to
>> objectively evaluate whether we should hold this for 9.3.  Comments?
>
> Well, I feel that one of the weaknesses of our CommitFest process is
> that changes like this (which are really pretty small) end up having
> the same deadline as patches that are large (command triggers,
> checksums, etc.); in fact, they sometimes end up having an earlier
> deadline, because the people doing the big stuff end up continuing to
> hack on it for another couple months while the door is shut to smaller
> improvements.  So I'm not going to object if you feel like slipping
> this one in.  I looked it over myself and I think it's broadly
> reasonable, although I'm not too sure about the particular criteria
> chosen for sending the WAL writer to sleep and waking it up again.
> And like you I'd like to see some more improvement in this area.

I agree that it's ok to slip it in given that it's "finishing off a
patch from earlier". I think it's reasonable to hold it to a little
bit higher review stadards since it's that late in the cycle though,
such as two people reviewing it before it goes in (or 1 reviewer + 1
committer - and of course, unless it's a truly trivial patch). Which
it seems you both are doing now, so that makes it ok ;)

--
 Magnus Hagander
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