Re: [Qemu-devel] [PATCH v2 00/15] SCSI s/g + SCSI migration + virtio-scsi

[Hu Tao]

On Thu, Feb 09, 2012 at 08:13:52AM +0100, Paolo Bonzini wrote:
> On 02/09/2012 06:46 AM, Hu Tao wrote:
> >>>>  >I've re-tested today, with host kernel 2.6.35.6-45.fc14.x86_64,
> >>>>  >2.6.32-71.el6.x86_64, 3.1.0 and 3.3.0-rc1+, qemu version and guest
> >>>>  >configuration remain the same, including guest kernel. It apears
> >>>>  >that the problem appears only when the host kernel version is 3.1.0.
> >Sorry, forget about the kernel versions. With very heavy IO load, it's
> >easy to reproduce the problem. In my case, 300 disks were attached to a
> >virtio-scsi HBA, and 300 dd processes were launched at the same time,
> >each for a disk.
> 
> Yes, we're not yet optimizing for _that_ kind of scalability. :)
> That raw works is already surprising enough to me!

Well, I'd like to say thanks for your works on virtio-scsi!

> 
> What disk was it?  Can you try on an SSD?

A Hitachi HDS721010CLA332, SATA II, 7200rpm. I'm afraid I can't test on
SSD since I have no SSD on hand.(and I don't think I'll have a SSD in
the near future :| )

-- 
Thanks,
Hu Tao