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Date: Sat, 09 Feb 2008 13:36:05 -0800
From: "H. Peter Anvin" <hpa@zytor.com>
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Subject: Re: [Qemu-devel] Re: 2.6.24 says "serial8250: too much work for irq4"
	a lot.
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To: Blue Swirl <blauwirbel@gmail.com>
Cc: qemu-devel@nongnu.org

Blue Swirl wrote:
>>
>> If you look at the patch, there are no timing dependencies; the only
>> parameter is the depth of the virtual queue.  The exhaustion is
>> completely controlled by target OS access patterns.
> 
> Thanks, this clarified the difference. But I'll rephrase my original comment:
> 
> The patch looks OK, but the simulated FIFO exhaustion should benefit
> all devices, as
> discussed here:
> http://lists.gnu.org/archive/html/qemu-devel/2007-12/msg00283.html

The difference is you *can't* do that in a general layer.

	-hpa