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Date: Thu, 8 Nov 2001 08:08:46 -0800 (PST)
From: Linus Torvalds <torvalds@transmeta.com>
To: Marcelo Tosatti <marcelo@conectiva.com.br>
cc: lkml <linux-kernel@vger.kernel.org>
Subject: Re: out_of_memory() heuristic broken for different mem configurations
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On Thu, 8 Nov 2001, Marcelo Tosatti wrote:
>
> I guess you forgot to apply the following patch on 2.4.15-pre1, right ?

The thing is, I _really_ think it is broken.

The way to make it fail is to have many large SHARED mappings - in which
case we have backing space for 99% of all memory, and returning -1 just
because a few pages need swap-space and can't be thrown out is wrong.

Try it with no swap, and having some processes that MAP_SHARED much more
than available memory and many (small) processes that do not, and need
swap-space. It should work fine - we're never even _close_ to being out of
memory, but your change makes "swap_out()" fail all the time.

		Linus

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