From: Jeff King <peff@peff.net>
To: Duy Nguyen <pclouds@gmail.com>
Cc: Patrick Hogg <phogg@novamoon.net>,
Git Mailing List <git@vger.kernel.org>,
Junio C Hamano <gitster@pobox.com>,
Johannes Schindelin <Johannes.Schindelin@gmx.de>,
Elijah Newren <newren@gmail.com>
Subject: Re: [PATCH v2] pack-objects: Use packing_data lock instead of read_mutex
Date: Tue, 22 Jan 2019 02:28:09 -0500 [thread overview]
Message-ID: <20190122072809.GA28975@sigill.intra.peff.net> (raw)
In-Reply-To: <CACsJy8AWCP+enBVVVga7jJZ-gxD=fxcushrk0D+xGSRAcZw_qg@mail.gmail.com>
On Mon, Jan 21, 2019 at 05:02:33PM +0700, Duy Nguyen wrote:
> > As I mentioned in the prior thread I think that it will be simpler
> > to simply use the existing lock in packing_data instead of moving
> > read_mutex. I can go back to simply moving read_mutex to the
> > packing_data struct if that that is preferable, though.
>
> In early iterations of these changes, I think we hit high contention
> when sharing the mutex [1]. I don't know if we will hit the same
> performance problem again with this patch. It would be great if Elijah
> with his zillion core machine could test this out. Otherwise it may be
> just safer to keep the two mutexes separate.
>
> [1] http://public-inbox.org/git/20180720052829.GA3852@sigill.intra.peff.net/
I haven't been following this thread closely, but I still have access to
a 40-core machine if you'd like me to time anything.
It sounds like _this_ patch is the more fine-grained one. Is the more
coarse-grained one already written?
-Peff
next prev parent reply other threads:[~2019-01-22 7:28 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-01-19 15:43 [PATCH v2] pack-objects: Use packing_data lock instead of read_mutex Patrick Hogg
2019-01-21 10:02 ` Duy Nguyen
2019-01-22 7:28 ` Jeff King [this message]
2019-01-22 10:25 ` Duy Nguyen
2019-01-22 13:13 ` Patrick Hogg
2019-01-22 17:52 ` Elijah Newren
2019-01-22 20:37 ` Elijah Newren
2019-01-22 22:43 ` Junio C Hamano
2019-01-22 23:54 ` Patrick Hogg
2019-01-23 17:51 ` Junio C Hamano
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