Re: intel iommu causing performance drop in mlx4 ipoib (OFFLIST)

Nikolay Borisov
2016-05-16T12:46:04Z

On 05/16/2016 03:39 PM, David Woodhouse wrote:
> On Mon, 2016-05-16 at 15:37 +0300, Nikolay Borisov wrote:
>>
>> Oops, turned out I had intel_iommu=on, though I'm sure some days ago I
>> didn't and performance suffered. I now tried with this option removed
>> and performance is again back to normal. All in all this driver +
>> intel_iommu is a bad combination I guess. Anyway, sorry for the noise
>> and thanks for the prompt reply.
>
> I would be very interested to see your results with the latest code
> from git://git.infradead.org/intel-iommu.git (and with the IOMMU still
> enabled).

Would I be able to apply this cleanly on 4.4, since this is the version
I'm currently using?