[ovs-discuss] Best 10GB adapter for offloading OVS

[Jesse Gross]

On Wed, Mar 27, 2013 at 11:13 AM, Kyle Mestery (kmestery)
<kmestery at cisco.com> wrote:
>
> On Mar 27, 2013, at 12:41 PM, Jesse Gross <jesse at nicira.com> wrote:
>
>> On Wed, Mar 27, 2013 at 6:06 AM, Atam <atamgp at gmail.com> wrote:
>>> Hi all,
>>>
>>> OVS is a software solution switch as i understand.  It is able to utilize
>>> offloading features of the Ethernet adapter I read somewhere...
>>>
>>> - What features are those? Is it desirable to invest in 10GB adapters with
>>> full TCP chimney support like Emulex (OCe11102) or Broadcom (57810S) ? Or is
>>> Intel intelligent offloading the same for OVS?
>>> - Is OVS using virtual function available on the adapter (now or in the
>>> future)?
>>>  e.g. Intel x540 adaters support 64 VF's per port. Around the same for
>>> Emulex and Broadcom.
>>> But Solarflare (SFN5121T) supports 254 VF's. Will that have an effect on
>>> OVM?
>>
>> OVS does not use any of these.  Most of them have implications for the
>> entire stack, so if you are using them currently (I suspect you are
>> not) you need to evaluate your requirements.
>>
> For VFs, there should be nothing special about how OVS uses those. The
> VFs each show up as a separate interface on the Linux host, and you can
> add those to OVS bridges as you would a normal physical link. Now if you
> want OVS to somehow orchestrate the VF creation process or something,
> that's outside the current scope of OVS.

It's true that if they are just exposed as devices to the host then
there is nothing special.  However, if they are mapped all the way to
the guest as SR-IOV then OVS obviously won't have any visibility.