Re: [Qemu-devel] [snabb-devel:300] Re: snabbswitch integration with QEMU for userspace ethernet I/O

[Julian Stecklina <jsteckli@os.inf.tu-dresden.de>]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On 06/04/2013 02:19 PM, Luke Gorrie wrote:
> The idea that excites me is to implement a complete PCI device in
> Snabb Switch and expose this to the guest at the basic PCI/MMIO/DMA
> level. The device would be a Virtio network adapter based on Rusty
> Russell's specification. The switch<->VM interface would be based
> on PCI rather than vhost.
> 
> I _think_ this is the basic idea that Stefano Stabellini and
> Julian Stecklina are talking about.

Yes. Btw, progress is being made. Albeit a bit slower than expected. I
will have to show something "soon".

[...]
> I have some questions, if you don't mind:
> 
> 1. Have I understood the idea correctly above? (Or what do I have
> wrong?)

AFAICS yes.

> 3. If I hack a proof-of-concept what is most likely to go wrong in
> an OpenStack context? I mean - the "memory hotplug" and "track what
> is dirty" issues that are alluded to. Is my code going to run
> slowly? drop packets? break during migration? crash VMs?

In the earliest implementation it will probably break during
migration. I hope this can be fixed, but since I don't understand the
magic qemu does for migration these days, I might be wrong.

Julian
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.19 (GNU/Linux)

iEYEARECAAYFAlGt4mcACgkQ2EtjUdW3H9k7IgCgiQJ81z1Zj5G5tED8EghKQlDe
gRQAniXzqTSadS7OvVHFQhKydbOFNkBn
=VBws
-----END PGP SIGNATURE-----