Re: [PATCH 0/4] pack-bitmap: enable lookup tables by default, misc. cleanups

[Patrick Steinhardt <ps@pks.im>]

On Fri, May 02, 2025 at 02:21:47PM -0700, Junio C Hamano wrote:
> Taylor Blau <me@ttaylorr.com> writes:
> 
> > This is a short series I extracted from a larger topic on reusing
> > "external"[^1] deltas during verbatim pack reuse.
> >
> > As part of performance-testing that series, I realized that bitmap
> > lookup tables are not written by default. Since it has been a
> > significant period of time since their introduction, the first patch of
> > this series makes writing the lookup table extension the default
> > behavior. This is:
> >
> >   * pack-bitmap: write lookup table extension by default
> >
> > The next three patches clean up some t/perf scripts that were redundant
> > now that lookup tables are the default behavior. Those are:
> >
> >   * p5312: removed duplicate performance test script
> >   * t/perf: avoid testing bitmaps without lookup table
> >   * t/perf/lib-bitmap.sh: avoid test_perf during setup
> >
> > Thanks in advance for your review :-).
> >
> > [^1]: The term I'm using to describe delta/base pairs which either (a)
> > are represented from different packs in a MIDX bitmap, or (b) the client
> > is known to already have the base.
> >
> > Taylor Blau (4):
> >   pack-bitmap: write lookup table extension by default
> >   p5312: removed duplicate performance test script
> >   t/perf: avoid testing bitmaps without lookup table
> >   t/perf/lib-bitmap.sh: avoid test_perf during setup
> 
> Peff and I were the only two people who read these patches?
> Is this topic still viable, or has it been backburnered?

I read through the patch series, but didn't have anything to add over
what has already been discussed. Overall I think that it makes sense to
enable lookup tables -- we've had them enabled since February 2023 for
all users of GitLab.

Patrick