On Tue, Oct 28, 2008 at 09:28:38AM -0400, Tom Lane wrote:
> Simon Riggs <simon@2ndQuadrant.com> writes:
> > On Sun, 2008-10-26 at 21:49 -0400, Tom Lane wrote:
> >> So I'm concluding that we can easily afford to switch to
> >> tuplestore-always operation, especially if we are willing to put any
> >> effort into tuplestore optimization. (I note that the current
> >> tuplestore code writes 24 bytes per row for this example, which is a
> >> shade on the high side for only 4 bytes payload. It looks like it
> >> would be pretty easy to knock 10 bytes off that for a 40% savings in
> >> I/O volume.)
>
> > That seems like an important, possibly more important, change.
>
> Yeah, seeing that both WITH and window functions will be stressing
> tuplestore performance, anything we can save there is probably worth the
> trouble.
>
> regards, tom lane
>
The pre-sort for index builds would also benefit from this change.
Ken