Re: 9.2beta1, parallel queries, ReleasePredicateLocks, CheckForSerializableConflictIn in the oprofile - Mailing list pgsql-hackers

From Tom Lane
Subject Re: 9.2beta1, parallel queries, ReleasePredicateLocks, CheckForSerializableConflictIn in the oprofile
Date
Msg-id 23608.1337963881@sss.pgh.pa.us
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In response to Re: 9.2beta1, parallel queries, ReleasePredicateLocks, CheckForSerializableConflictIn in the oprofile  (Merlin Moncure <mmoncure@gmail.com>)
Responses Re: 9.2beta1, parallel queries, ReleasePredicateLocks, CheckForSerializableConflictIn in the oprofile
List pgsql-hackers
Merlin Moncure <mmoncure@gmail.com> writes:
> On Fri, May 25, 2012 at 11:17 AM, Stephen Frost <sfrost@snowman.net> wrote:
>> Didn't we implement a system whereby this is exactly what we intend to
>> happen on the read side- that is, everyone doing a SeqScan gangs up on
>> one ring buffer and follows it, which we felt was going to dramatically
>> improve performance in some cases?

> yeah:
> ...
> I wonder if the logic here is just being too strict...

I don't recall how much evidence there is behind the NBuffers/4 threshold.
Maybe that needs some tuning?
        regards, tom lane


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