Re: Logical tape pause/resume

On Wed, Dec 21, 2016 at 4:25 AM, Heikki Linnakangas <hlinnaka(at)iki(dot)fi> wrote:
> In the meanwhile, Robert committed the cap on the number of tapes. Since
> that's in, I'm not sure if the pause/resume part of this is worthwhile.
> Maybe it is.

I rebased my parallel tuplesort patch on top of what you committed a
few days back (your 0001-* patch). It definitely made my changes to
logtape.c significantly simpler, which was a big improvement.

I would be inclined to not go forward with 0002-* though, because I
think it's cleaner for the parallel tuplesort patch to have workers
rely on the tape freezing code to flush the last block out to make
state available in temp files for the leader to process/merge. The
memory savings that remain on the table are probably not measurable if
we were to fix them, given the work we've already done, palloc()
fragmentation, and so on.

--
Peter Geoghegan