On Mon, Nov 5, 2012 at 2:09 PM, Jeff Janes <jeff.janes@xxxxxxxxx> wrote: >>> In my experience when doing sorts in isolation, having more work_mem >>> is a bad thing, unless it enables you to remove a layer of >>> tape-merging. I always blamed it on the L1/L2 etc. levels of caching. >> >> Blame it on quicksort, which is quite cache-unfriendly. > > The observation applies to heap sort. Well, heapsort is worse, but quicksort is also quite bad. -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
