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Message-ID: <4b9fd98f.0c58560a.205a.0a38@mx.google.com>
Date: Tue, 16 Mar 2010 12:18:39 -0700 (PDT)
From: Ben Gamari <bgamari.foss@gmail.com>
To: martin f krafft <madduck@madduck.net>, "Aneesh Kumar K. V"
	<aneesh.kumar@linux.vnet.ibm.com>
In-Reply-To: <20100316180052.GA6600@piper.oerlikon.madduck.net>
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	<20100316180052.GA6600@piper.oerlikon.madduck.net>
Cc: Olly Betts <olly@survex.com>, notmuch@notmuchmail.org
Subject: Re: [notmuch] Notmuch performance (literally, in my case)
Precedence: list

On Tue, 16 Mar 2010 19:00:52 +0100, martin f krafft <madduck@madduck.net> wrote:
> I use ext4 with data=ordered, and while notmuch is writing the
> Xapian database, most I/O stalls on the machine:
> 
>   - Firefox does not get any mouse events
>   - Vim blocks writing the viminfo file
>   - All disk operations queue for multiple seconds.
> 
> So no, ext4 is not a solution. Is it just me, or should no
> filesystem of this world be able to hog a system this badly? I think
> the culprit is the IO-scheduler.
> 
In my uninformed opinion, I think it more likely that the dominant factor is
the page reclaim code. Even noop scheduling is pretty bad.

- Ben