Re: 8.3devel slower than 8.2 under read-only load

On Mon, 2007-11-26 at 09:55 -0500, Tom Lane wrote:
> Simon Riggs <simon@2ndquadrant.com> writes:
> > But I think there must be an action that we can take for 8.3 and that
> > much runtime should not be given away easily. ISTM that we can win back
> > the losses Guillaume has identified, plus gain a little more even.
> 
> Perhaps some sanity could be restored to this discussion by pointing out
> that the 2007-01-01 code *also* clocks in at 37% spent in
> oper_select_candidate.  IOW it's been like this for a very long time.
> I'm not interested in destabilizing 8.3 with panicky last-minute patches.

I think this is worth taking action on, IMHO.

I've written up my suggestion as a 5 line patch, with measured
performance improvement of about 40% for the varchar case. 

It isn't a great long term fix, but I don't want to delay 8.3 either
with the full fix.

--  Simon Riggs 2ndQuadrant  http://www.2ndQuadrant.com