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Date: Fri, 15 May 2009 17:15:54 -0400 (EDT)
From: Christoph Lameter <cl@linux-foundation.org>
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To: Pavel Machek <pavel@ucw.cz>
cc: Dave Hansen <dave@linux.vnet.ibm.com>,
       David Rientjes <rientjes@google.com>,
       Andrew Morton <akpm@linux-foundation.org>,
       Greg Kroah-Hartman <gregkh@suse.de>, Nick Piggin <npiggin@suse.de>,
       Mel Gorman <mel@csn.ul.ie>, Peter Ziljstra <a.p.ziljstra@chello.nl>,
       San Mehat <san@android.com>, Arve Hj?nnev?g <arve@android.com>,
       linux-kernel@vger.kernel.org
Subject: Re: Misleading OOM messages
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On Fri, 15 May 2009, Pavel Machek wrote:

> > Nope. If you have too little memory for your app then the kernel pages
> > portions of the app out to disk. Thats is why you have a VM (VIRTUAL
> > machine). The app is not running with physical memory.
>
> Try running your machine with mem=8M, then tell me how virtual memory
> works.

Well that is of course not enough memory. And you intentionally screwed up
your setup.

> If you have *way* too little RAM, you OOM. (Kernel data is
> unswappable. Task struct is 8KB. At some point it breaks).

I do not see anyone doubting that this is the case.