From mboxrd@z Thu Jan  1 00:00:00 1970
From: torvalds@linux-foundation.org (Linus Torvalds)
Date: Mon, 9 Feb 2009 21:23:56 -0800 (PST)
Subject: [ltt-dev] [PATCH] mm fix page writeback accounting to fix oom
 condition under heavy I/O
In-Reply-To: <20090210033652.GA28435@Krystal>
References: <20090120122855.GF30821@kernel.dk> <20090120232748.GA10605@Krystal>
	<20090123220009.34DF.KOSAKI.MOTOHIRO@jp.fujitsu.com>
	<20090210033652.GA28435@Krystal>
Message-ID: <alpine.LFD.2.00.0902092120450.3048@localhost.localdomain>



On Mon, 9 Feb 2009, Mathieu Desnoyers wrote:
> 
> So this patch fixes this behavior by only decrementing the page accounting
> _after_ the block I/O writepage has been done.

This makes no sense, really.

Or rather, I don't mind the notion of updating the counters only after IO 
per se, and _that_ part of it probably makes sense. But why is it that you 
only then fix up two of the call-sites. There's a lot more call-sites than 
that for this function. 

So if this really makes a big difference, that's an interesting starting 
point for discussion, but I don't see how this particular patch could 
possibly be the right thing to do.

			Linus