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Date: Thu, 22 Mar 2001 20:16:44 -0300 (BRST)
From: Rik van Riel <riel@conectiva.com.br>
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To: Richard Jerrell <jerrell@missioncriticallinux.com>
Cc: <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] mm/memory.c, 2.4.1 : memory leak with swap cache (updated)
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On Thu, 22 Mar 2001, Richard Jerrell wrote:

> 2.4.1 has a memory leak (temporary) where anonymous memory pages
> that have been moved into the swap cache will stick around after
> their vma has been unmapped by the owning process.

> free_pte in mm/memory.c has been modified to check to see if the
> page is only being referenced by the swap cache

Your idea is nice, but the patch lacks a few things:

- SMP locking, what if some other process faults in this page
  between the atomic_read of the page count and the test later?
- testing if our process is the _only_ user of this swap page,
  for eg. apache you'll have lots of COW-shared pages .. it would
  be good to keep the page in memory for our siblings

regards,

Rik
--
Linux MM bugzilla: http://linux-mm.org/bugzilla.shtml

Virtual memory is like a game you can't win;
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