On Mon, Nov 5, 2012 at 2:09 PM, Jeff Janes <[email protected]> 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 ([email protected]) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
