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Date: Sun, 12 Oct 2008 16:35:46 +0100
From: Jamie Lokier <jamie@shareable.org>
Subject: Re: [Qemu-devel] [RFC] Disk integrity in QEMU
Message-ID: <20081012153546.GD18814@shareable.org>
References: <48EE38B9.2050106@codemonkey.ws> <48EF1D55.7060307@redhat.com>
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To: qemu-devel@nongnu.org
Cc: Chris Wright <chrisw@redhat.com>, Mark McLoughlin <markmc@redhat.com>, Ryan Harper <ryanh@us.ibm.com>, kvm-devel <kvm@vger.kernel.org>, Laurent Vivier <Laurent.Vivier@bull.net>

Dor Laor wrote:
> Actually this is what happens on mainline qemu with cache=off.

Have I understood right that cache=off on a qcow2 image only uses
O_DIRECT for the leaf image, and the chain of base images don't use
O_DIRECT?

Sometimes on a memory constrained host, where the (collective) guest
memory is nearly as big as the host memory, I'm not sure this is what
I want.

-- Jamie