Re: Deferring some AtStart* allocations?

On 2014-10-09 17:02:02 -0400, Robert Haas wrote:
> On Thu, Oct 9, 2014 at 3:53 PM, Andres Freund <andres@2ndquadrant.com> wrote:
> >> OK, here's an attempt at a real patch for that.  I haven't perf-tested this.
> >
> > Neato. With a really trivial SELECT:
> >
> > before:
> > tps = 28150.794776 (excluding connections establishing)
> > after:
> > tps = 29978.767703 (excluding connections establishing)
> >
> > slightly more meaningful:
> >
> > before:
> > tps = 21272.400039 (including connections establishing)
> > after:
> > tps = 22290.703482 (excluding connections establishing)
> >
> > So that's a noticeable win. Obviously it's going to be less for more
> > complicated stuff, but still...
> >
> > I've not really looked at the patches though.
> 
> Yeah, not bad at all for the amount of work involved.  Want to
> disclose the actual queries?

SELECT 1;
SELECT * FROM smalltable WHERE id = xxx;

The latter is something quite frequent in the real world, so it's not
all academic...

Greetings,

Andres Freund

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