Re: Deferring some AtStart* allocations? - Mailing list pgsql-hackers

On 2014-10-09 08:18:18 -0400, Robert Haas wrote:
> On Thu, Oct 9, 2014 at 5:34 AM, Andres Freund <andres@2ndquadrant.com> wrote:
> > Interesting - in my local profile AtStart_Inval() is more pronounced
> > than AfterTriggerBeginQuery(). I've quickly and in a ugly fashion hacked
> > AtStart_Inval() out of readonly queries ontop of your patch. Together
> > that yields a ~3.5% performance improvement in my trivial 'SELECT * FROM
> > tbl WHER pkey = xxx' testcase.
> 
> Whoa.  Now that's clearly significant.

Well, my guess it'll be far less noticeable in less trivial
workloads. But it does seem worthwile.

> You didn't attach the patch; was that inadvertent, or was it too ugly
> for that?

Far, far too ugly ;). I just removed the AtStart() call from xact.c and
sprinkled it around relevant places instead ;)

Greetings,

Andres Freund

-- Andres Freund                       http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
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