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Date: Mon, 3 Oct 2005 15:58:40 +0200
From: Jens Axboe <qemu@kernel.dk>
Subject: Re: [Qemu-devel] [patch] non-blocking disk IO
Message-ID: <20051003135837.GC3511@suse.de>
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To: qemu-devel@nongnu.org

On Mon, Oct 03 2005, John Coiner wrote:
> 
> Non-blocking disk IO now works for any type of disk image, not just 
> "raw" format. There is no longer any format-specific code in the patch:
> 
> http://people.brandeis.edu/~jcoiner/qemu_idedma/qemu_dma_patch.html
> 
> You might want this patch if:
>  * you run a multitasking guest OS,
>  * you access a disk sometimes, and
>  * you wouldn't mind if QEMU ran a little faster.
> 
> Why I have not got feedback in droves I do not understand ;)

Why not use aio for this instead, seems like a better fit than spawning
a thread per block device? That would still require a thread for
handling completions, but you could easily just use a single completion
thread for all devices for this as it would not need to do any real
work.

-- 
Jens Axboe