From: David Kastrup <dak@gnu.org>
To: Jeff King <peff@peff.net>
Cc: git@vger.kernel.org
Subject: Re: [PATCH v2] Bump core.deltaBaseCacheLimit to 128MiB
Date: Fri, 21 Mar 2014 07:12:40 +0100 [thread overview]
Message-ID: <87txascc6f.fsf@fencepost.gnu.org> (raw)
In-Reply-To: <20140320234859.GD7774@sigill.intra.peff.net> (Jeff King's message of "Thu, 20 Mar 2014 19:48:59 -0400")
Jeff King <peff@peff.net> writes:
> On Wed, Mar 19, 2014 at 01:38:32PM +0100, David Kastrup wrote:
>
>> The default of 16MiB causes serious thrashing for large delta chains
>> combined with large files.
>
> Does it make much sense to bump this without also bumping
> MAX_DELTA_CACHE in sha1_file.c? In my measurements of linux.git, bumping
> the memory limit did not help much without also bumping the number of
> slots.
In the cases I checked, bumping MAX_DELTA_CACHE did not help much.
Bumping it once to 512 could be a slight improvement; larger values then
caused performance to regress.
> I guess that just bumping the memory limit would help with repos which
> have deltas on large-ish files (whereas the kernel just has a lot of
> deltas on a lot of little directories),
Well, those were the most pathological for git-blame so I was somewhat
focused on them.
> but I'd be curious how much.
http://repo.or.cz/r/wortliste.git
consists basically of adding lines to a single alphabetically sorted
file wortliste of currently size 15MB.
--
David Kastrup
next prev parent reply other threads:[~2014-03-21 7:48 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-03-19 12:38 [PATCH v2] Bump core.deltaBaseCacheLimit to 128MiB David Kastrup
2014-03-19 21:09 ` Junio C Hamano
2014-03-19 21:25 ` David Kastrup
2014-03-19 22:11 ` Junio C Hamano
2014-03-20 1:38 ` Duy Nguyen
2014-03-20 17:02 ` Junio C Hamano
2014-03-20 17:08 ` David Kastrup
2014-03-20 22:35 ` Junio C Hamano
2014-03-21 6:04 ` David Kastrup
2014-03-21 7:59 ` Duy Nguyen
2014-03-21 8:02 ` David Kastrup
2014-03-20 23:48 ` Jeff King
2014-03-21 6:12 ` David Kastrup [this message]
2014-03-21 8:11 ` David Kastrup
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