From: David Mosberger <davidm@napali.hpl.hp.com>
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Message-ID: <16463.28724.277502.132751@napali.hpl.hp.com>
Date: Wed, 10 Mar 2004 11:44:52 -0800
To: Arun Sharma <arun.sharma@intel.com>
Cc: davidm@hpl.hp.com, linux-ia64@vger.intel.com
Subject: Re: Virtual memory leaking through IA32 emulation layer for mmap
   and munmap
In-Reply-To: <404F6D26.8010502@intel.com>
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	<16461.5771.740526.489351@wombat.chubb.wattle.id.au>
	<16461.6191.949155.778550@napali.hpl.hp.com>
	<20040310035801.GC23596@tlaloc.n0ano.com>
	<Pine.LNX.4.58.0403101614500.22838@sutekh.progsoc.uts.edu.au>
	<mailman.1078940988.14439@unix-os.sc.intel.com>
	<404F6D26.8010502@intel.com>
Reply-To: davidm@hpl.hp.com

>>>>> On Wed, 10 Mar 2004 11:31:50 -0800, Arun Sharma <arun.sharma@intel.com> said:

  Arun> Yes, I'd really like to see this problem fixed. I think, the
  Arun> patch needs to be as memory efficient as possible - we're
  Arun> using non-pageable kernel memory. So some numbers on the two
  Arun> level bitmap scheme vs keeping lists of head/tail pages for
  Arun> common ia32 workloads would be good.

Agreed.  The good news is that the track is only needed for parially
allocated pages, so the overhead should, in the worst-case, be
proportional to the number of vmareas, not to the amount of memory
mapped.

	--david