Robert Treat <xzilla@users.sourceforge.net> writes:
> On Tuesday 25 July 2006 14:28, Josh Berkus wrote:
>> To be quite frank, current PostgreSQL can't effectively use more than
>> 256mb of work_mem anyway. We'd like to fix that, but it's not fixed yet
>> AFAIK.
> Josh, can you clarify this statement for me?
Perhaps I shouldn't put words in Josh' mouth, but I *think* what he
meant is that the tuplesort code does not get any faster once work_mem
exceeds a few hundred meg. I believe we've addressed that to some
extent in CVS HEAD, but it's a fair gripe against the existing release
branches.
I'm not aware that anyone has done any work to characterize performance
vs work_mem setting for any of the other uses of work_mem (such as hash
table sizes).
regards, tom lane