Re: Flurries of 'git reflog expire'

From: Andreas Krey <a.krey@gmx.de>
Date: Jul 6, 2017, 13:31 UTC
Message-ID: <20170706133124.GB1216@inner.h.apk.li>
In-Reply-To: <20170705082027.ujddejajjlvto7bp@sigill.intra.peff.net>

On Wed, 05 Jul 2017 04:20:27 +0000, Jeff King wrote:

> On Tue, Jul 04, 2017 at 09:57:58AM +0200, Andreas Krey wrote:

...

> I seem to recall that using --stale-fix is also extremely expensive,
> too. What do the command line arguments for the slow commands look like?

The problem isn't that the expire is slow, it is that there are many of them, waiting for disk writes.

> And what does the process tree look like?

Lots (~ 10) of

          \_ /usr/bin/git receive-pack /opt/apps/atlassian/bitbucket-data/shared/data/repositories/68
          |   \_ git gc --auto --quiet
          |       \_ git reflog expire --all

plus another dozen gc/expire pairs where the parent is already gone. All with the same arguments - auto GC.

I'd wager that each push sees that a GC is in order, and doesn't notice that there is one already running.

- Andreas

-- 
"Totally trivial. Famous last words."
From: Linus Torvalds <torvalds@*.org>
Date: Fri, 22 Jan 2010 07:29:21 -0800