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Date: Tue, 03 Aug 2010 22:24:41 +0300
From: Avi Kivity <avi@redhat.com>
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Subject: Re: [Qemu-devel] Anyone seeing huge slowdown launching qemu with
	Linux 2.6.35?
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To: Anthony Liguori <anthony@codemonkey.ws>
Cc: kvm@vger.kernel.org, "Richard W.M. Jones" <rjones@redhat.com>, Gleb Natapov <gleb@redhat.com>, qemu-devel@nongnu.org

  On 08/03/2010 10:15 PM, Anthony Liguori wrote:
>
> fw_cfg has to be available pretty early on so relying on a PCI device 
> isn't reasonable.  Having dual interfaces seems wasteful.

Agree.

>
> We're already doing bulk data transfer over fw_cfg as we need to do it 
> to transfer roms and potentially a boot splash. 

Why do we need to transfer roms?  These are devices on the memory bus or 
pci bus, it just needs to be there at the right address.  Boot splash 
should just be another rom as it would be on a real system.

> Even outside of loading an initrd, the performance is going to start 
> to matter with a large number of devices.

I don't really see why.

-- 
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.