Re: [PATCH] mm/memory.c, 2.4.1 : memory leak with swap cache (updated)

From: Rik van Riel (riel@conectiva.com.br)
Date: Thu Mar 22 2001 - 18:16:44 EST

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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This archive was generated by hypermail 2b29 : Fri Mar 23 2001 - 21:00:18 EST