[systemd-devel] persisting sriov_numvfs

[Martin Polednik]

----- Original Message -----
> From: "Lennart Poettering" <lennart at poettering.net>
> To: "Andrei Borzenkov" <arvidjaar at gmail.com>
> Cc: "Martin Polednik" <mpolednik at redhat.com>, systemd-devel at lists.freedesktop.org, ibarkan at redhat.com
> Sent: Tuesday, January 27, 2015 1:21:32 PM
> Subject: Re: [systemd-devel] persisting sriov_numvfs
> 
> On Tue, 27.01.15 06:47, Andrei Borzenkov (arvidjaar at gmail.com) wrote:
> 
> > > Hmm, I see. In many ways this feels like VLAN setup from a
> > > configuration PoV, right? i.e. you have one hw device the driver
> > > creates, and then you configure a couple of additional interfaces on
> > > top of it.
> > > 
> > > This of course then raises the question: shouldn't this functionality
> > > be exposed by the kernel the same way as VLANs? i.e. with a
> > > rtnetlink-based API to create additional interfaces, instead of /sys?
> > > 
> > > In systemd I figure the right way to expose this to the user would be via
> > > .netdev files, the same way as we expose VLAN devices. Not however
> > > that that would be networkd territory,
> > 
> > No, this is not limited to NICs. It is generic feature that can be in
> > principle used with any hardware and there are e.g. FC or FCoE HBAs
> > with SR-IOV support. It is true that today it is mostly comes with NICs
> > though.
> > 
> > Any general framework for setting it up should not be tied to specific
> > card type.
> 
> Well, I doubt that there will be graphics cards that support this
> right? I mean, it's really only network connectivity that can support
> a concept like this easily, since you can easily merge packet streams
> from multiple VMs on one connection. However, I am not sure how you
> want to physically merge VGA streams onto a single VGA connector...
> 
> If this is about ethernet, FC, FCOE, then I still think that the
> network management solution should consider this as something you can
> configure on physical links like VLANs. Hence networkd or
> NetworkManager and so on should cover it.
> 
> Lennart

Afaik some storage cards support this, for GPU's it's possibly for the
GPUPU applications and such - where you don't care about the physical
output, but the processing core of gpu itself (but I'm not aware of such
implementation yet, nvidia seems to be doing something but the details
are nowhere to be found).
 
> --
> Lennart Poettering, Red Hat
>