From mboxrd@z Thu Jan  1 00:00:00 1970
From: Iustin Pop <iusty@k1024.org>
Subject: Re: Reducing impact of save/restore/dump on Dom0
Date: Tue, 6 Feb 2007 18:36:45 +0100
Message-ID: <20070206173645.GB6768@teal.hq.k1024.org>
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To: "Graham, Simon" <Simon.Graham@stratus.com>
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On Tue, Feb 06, 2007 at 10:43:41AM -0500, Graham, Simon wrote:
> Currently, save, restore and dump all used cached I/O in Dom0 to
> write/read the file containing the memory image of the DomU - when the
> memory assigned to the DomU is greater than free memory in Dom0, this
> leads to severe memory thrashing and generally the Dom0 performance goes
> into the toilet.

On linux, there is another way beside O_DIRECT: it's possible to reduce
the memory used for cached writing using the sysctl vm.dirty_ratio; I've
used this to reduce the impact of heavy cached writes on dom0 with good
results.

Maybe it helps for save/dump also...

Regards,
Iustin