Re: Polyphase merge is obsolete

On Sat, Jan 23, 2021 at 3:49 AM Heikki Linnakangas <hlinnaka@iki.fi> wrote:
>
> On 22/10/2020 14:48, Heikki Linnakangas wrote:
> > On 11/09/2017 13:37, Tomas Vondra wrote:
> >> I planned to do some benchmarking on this patch, but apparently the
> >> patch no longer applies. Rebase please?
> >
> > Here's a rebase of this. Sorry to keep you waiting :-).
>
> Here's an updated version that fixes one bug:
>
> The CFBot was reporting a failure on the FreeBSD system [1]. It turned
> out to be an out-of-memory issue caused by an underflow bug in the
> calculation of the size of the tape read buffer size. With a small
> work_mem size, the memory left for tape buffers was negative, and that
> wrapped around to a very large number. I believe that was not caught by
> the other systems, because the other ones had enough memory for the
> incorrectly-sized buffers anyway. That was the case on my laptop at
> least. It did cause a big slowdown in the 'tuplesort' regression test
> though, which I hadn't noticed.
>
> The fix for that bug is here as a separate patch for easier review, but
> I'll squash it before committing.

The patch does not apply on Head anymore, could you rebase and post a
patch. I'm changing the status to "Waiting for Author".

Regards,
Vignesh