[ovs-discuss] switch flow self-insertion

[Grzegorz]

I'm taking about hash based on which flow table is looked up in kernel data
path.

czw., 5 lip 2018 o 20:20 Ben Pfaff <blp at ovn.org> napisał(a):

> Which hash are you talking about?  OVS has lots of hashes all over.
>
> On Thu, Jul 05, 2018 at 07:46:57PM +0200, Grzegorz wrote:
> > Hi Ben,
> > You're absolutely right. Thank you! Now I understand how it works.
> >
> > So having such the knowledge I have another question. In order to
> implement
> > other part of our mechanism I need to place in kernel space only flows
> that
> > for which mach (hash) is done based only on MPLS label. If I correct
> > understand how OVS worsk, the hash is done based on all header fields.
> So I
> > need to put somewhere in code simple if statement, i.e.:
> >
> > if (packet is tagged with MPLS)
> >    hash = label_number
> > else
> >    proceed_regular_hash_calculation
> >
> > Could someone point me a place where such the statement should be placed
> in
> > the code? Thank you in advance.
> >
> >
> >
> >
> >
> >
> >
> >
> > czw., 5 lip 2018 o 18:56 Ben Pfaff <blp at ovn.org> napisał(a):
> >
> > > On Thu, Jul 05, 2018 at 10:32:23AM +0200, Grzegorz wrote:
> > > > We want to make some OSV code modification in order to obtain
> > > fuctionality
> > > > desribed in https://arxiv.org/pdf/1805.07993.pdf
> > > > Strictly speaking wa want to implement the part related to Figure 4
> on
> > > page
> > > > 10. In shortcut, the proposed mechanism uses 2 flow tables (Detailed
> and
> > > > Coarse Flow Table, DTF and CFT). The first stores exact 5-tuple
> match,
> > > when
> > > > the latter cotains match based on only destination network. When a
> flow
> > > is
> > > > missed in DFT, the second table is looked up. When the match is
> found in
> > > > CFT, a packated is proccessed according to this much and
> simultaneously
> > > > switch prepares a new match based on this packet 5-tuple and acctions
> > > > copied from CFT. Such flow is inserted by switch into DFT itself.
> > >
> > > This sounds like what OVS already does with its multiple layers of
> > > caches, or possibly with connection tracking.  What's new about your
> > > design?
> > >
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.openvswitch.org/pipermail/ovs-discuss/attachments/20180705/cf422b72/attachment.html>