From: Jiri Kosina <jkosina@suse.cz>
To: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: ksummit-discuss@lists.linuxfoundation.org
Subject: Re: [Ksummit-discuss] No more module removal -- Unconference track
Date: Mon, 25 Aug 2014 13:05:30 +0200 (CEST) [thread overview]
Message-ID: <alpine.LNX.2.00.1408251304260.2992@pobox.suse.cz> (raw)
In-Reply-To: <53FB17A7.9090209@hitachi.com>
On Mon, 25 Aug 2014, Masami Hiramatsu wrote:
> What I found is that the module unloading involving 2 stop_machine()s
> for each module removing. It must not be needed. However, since the
> module's ref-counter is over-optimized for BIG SMP machine, we can't
> remove it without replacing it. But it means some performance regression
> can happen on such big-scale SMP machines (not the laptop nor normal smp
> machine).
Is that really a big problem in practice?
I.e. are there valid usecase scenarios where module load / unload should
be considered a hotpath where every ms of performance would matter?
Thanks,
--
Jiri Kosina
SUSE Labs
next prev parent reply other threads:[~2014-08-25 11:05 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-08-19 14:48 Theodore Ts'o
2014-08-19 14:55 ` Guenter Roeck
2014-08-19 15:23 ` Theodore Ts'o
2014-08-19 15:40 ` Dan Carpenter
2014-08-19 15:47 ` Guenter Roeck
2014-08-19 16:09 ` Dan Carpenter
2014-08-19 16:34 ` Martin K. Petersen
2014-08-19 16:59 ` Rik van Riel
2014-08-19 17:19 ` Guenter Roeck
2014-08-19 16:43 ` David Woodhouse
2014-08-19 17:13 ` Grant Likely
2014-08-19 17:23 ` David Woodhouse
2014-08-19 15:54 ` Takashi Iwai
2014-08-25 11:01 ` Masami Hiramatsu
2014-08-25 11:05 ` Jiri Kosina [this message]
2014-08-26 5:24 ` Masami Hiramatsu
2014-08-27 23:05 ` Theodore Ts'o
2014-08-26 21:39 ` David Howells
2014-08-26 21:45 ` Jiri Kosina
2014-08-27 6:43 ` Masami Hiramatsu
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