Re: tuplesort memory usage: grow_memtuples - Mailing list pgsql-hackers

On 14 October 2012 09:19, Simon Riggs <simon@2ndquadrant.com> wrote:
> This is a very useful optimisation, for both the low and the high end.

Well, I'm about ready to mark this one "ready for committer". There is
this outstanding issue in my revision of August 17th, though:

+         /*
+          * XXX: This feels quite brittle; is there a better principled approach,
+          * that does not violate modularity?
+          */
+         newmemtupsize = (int) floor(oldmemtupsize * allowedMem / memNowUsed);
+         state->fin_growth = true;

I suppose that I should just recognise that this *is* nothing more
than a heuristic, and leave it at that.

-- 
Peter Geoghegan       http://www.2ndQuadrant.com/
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