Re: [PATCH 0/3] switch to tombstone-free khashl table

From: Junio C Hamano <gitster@pobox.com>
Date: Mar 26, 2024, 17:40 UTC
Message-ID: <xmqqy1a4ao3t.fsf@gitster.g>
In-Reply-To: <20240325230704.262272-1-e@80x24.org>

Eric Wong <e@80x24.org> writes:

Show 6 quoted lines

> The memory improvement is minor, but any memory reduction at all
> is welcome at this point.  Fortunately, this set of changes is
> unintrusive.
>
> I have some other ideas that I'll hopefully get to implement before
> swapping kills all my SSDs (see bottom).

Please describe what this topic aims at to sell the topic better. Are we trying to reduce memory footprint? In other words, if this topic were to hit a released version of Git, what would the short paragraph description for the topic in the release notes look like?

 * The khash.h hashtable implementation has been replaced with
   khashl.h that is mostly API compatible with reduced memory
   consumption, simpler insertion and a bit slower deletion.

or somesuch.

A performance oriented topic would be helped to have benchmark numbers to show how much improvement it makes and a memory reduction topic would be helped to have some numbers in the cover letter. It is OK to summarize/duplicate what appears in the proposed log message of some step; it does not need too much text to say 100MB total allocations reduced by 10MB or something like that, for example.

An API improvement topic would be helped to have an example rewrite of a caller (or just a reference to a representative one, i.e., "see how the caller in function X gets simplified in [PATCH 04/28]") in the cover letter.

A bugfix topic would be helped to have an end-user visible effect in the cover letter.

Thanks.