Re: [PATCH 2/2] libxl: switch NetBSD image file handling to Qemu

[Thor Lancelot Simon <tls%panix.com@localhost>]

On Wed, Nov 28, 2012 at 02:20:51PM +0100, Roger Pau Monne wrote:
> This forces libxl to use Qemu when a raw image file is used as a disk
> backend. NetBSD currently only supports qemu-traditional, so

Wait -- do I grasp correctly that this patch _forces_ NetBSD as a dom0
to handle file-backed I/O requests in a way that includes additional
context switches to userspace, and which your previous email said
resulted in a 30% reduction in throughput compared to dom0 I/O?

I am assuming there's some reason we want this, rather than handling
such requests in-kernel.  But what is it?

Thor