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Date: Mon, 25 May 2009 14:58:52 +0200
From: Samuel Thibault <samuel.thibault@gnu.org>
Subject: Re: [Qemu-devel] Do we need CONFIG_AIO?
Message-ID: <20090525125852.GK5909@const.bordeaux.inria.fr>
References: <20090525082151.GA4107@lst.de> <4A1A85B4.3060200@eu.citrix.com>
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To: Christoph Hellwig <hch@lst.de>
Cc: "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>, Stefano Stabellini <stefano.stabellini@eu.citrix.com>

Christoph Hellwig, le Mon 25 May 2009 14:29:29 +0200, a écrit :
> On Mon, May 25, 2009 at 12:49:08PM +0100, Stefano Stabellini wrote:
> > > Is there any Posix-ish platform qemu supports that does not have
> > > pthreads support?
> > > 
> > 
> > MiniOS.
> > I would appreciate if you keep that flag.
> 
> I can't find MiniOS mentioned anywhere in the qemu tree.  From googling
> around it seems to be some Xen demo kernel.  Do you plan to merge
> support for it one day?  And what's the use case for qemu on MiniOS?
> If it's anything performance sensitive the lack of aio will cause quite
> severe stalling of the guest.

qemu on MiniOS is used to provide efficient full virtualisation, so yes
it's performance sensitive, but for performances we use a block-vbd
interface. Keeping the block-posix interface for non-performance
critical resources that can not go through vbd is still important, so we
need to be able to compile it.

Samuel