Date: Tue, 23 Oct 2012 11:04:34 +0200
From: Julian Wollrath <jwollrath@web.de>
To: Hugh Dickins <hughd@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
        Julian Wollrath <jwollrath@web.de>,
        Patrik Kullman <patrik.kullman@gmail.com>,
        linux-kernel <linux-kernel@vger.kernel.org>, linux-mm@kvack.org,
        David Rientjes <rientjes@google.com>
Subject: Re: Major performance regressions in 3.7rc1/2
Message-ID: <20121023110434.021d100b@ilfaris>
In-Reply-To: <alpine.LNX.2.00.1210222059120.1136@eggly.anvils>
References: <CAGPN=9Qx1JAr6CGO-JfoR2ksTJG_CLLZY_oBA_TFMzA_OSfiFg@mail.gmail.com>
	<20121022173315.7b0da762@ilfaris>
	<20121022214502.0fde3adc@ilfaris>
	<20121022170452.cc8cc629.akpm@linux-foundation.org>
	<alpine.LNX.2.00.1210222059120.1136@eggly.anvils>
Mime-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 1617
Lines: 31

> > Thanks.  Let's add some cc's.  Can you please describe your workload
> > and some estimate of the slowdown?
I am using fluxbox with Iceweasel, Claws-Mail and urxvt on different
workspaces on a Thinkpad X121e with an AMD E-450 APU. Loading some big
pages in Iceweasel leades to a very sluggish rendering of the urxvt
window when changing workspaces, the cursor movement falters. The
falter in the cursor movement is from random length but I would
estimate, that it is mostly under one second. But sometimes the time
between the each falter is very short which results in a more or less
unusable system.

> I'm currently assuming that my clear_page_mlock() commit is innocent
> of this: it went in just two before David's numa reclaim commit, and
> I don't see how mine could have any such marked effect: I'm thinking
> it was just a bisection hiccup that implicated it.
Just tested v3.7-rc2 with your clear_page_mlock() and without the numa
reclaim commit and everything worked fine. So you are right, most
probable it was a bisection hiccup, the reclaim commit is the real bad
commit. Nevertheless I am wondering why everything worked fine until
39b5f29a (mm: remove vma arg from page_evictable) and then started to
behave badly with your clear_page_mlock() commit but 3.7-rc2 works fine
with only the numa reclaim commit revoked.


With best regards,
Julian Wollrath
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/