[ovs-discuss] Is flow extraction on the critical path

[Justin Pettit]

It depends on the port, but any reasonable implementation would do the parsing in hardware.  Current merchant switching ASICs can't typically match on the full set of fields defined in OpenFlow, so often times a hardware port will only offer line rate for a subset.

--Justin


On Jan 19, 2012, at 9:25 PM, K.Kalapriya wrote:

> hi, 
> 
> One more query, Is this flow extraction typically done by a software module even in hardware switches or it is perhaps performed by a specialized and optimized hardware in hardware switches?
> 
> regards,
> kalapriya.
> 
> From: Justin Pettit <jpettit at nicira.com>
> To: K.Kalapriya <kalapriya at yahoo.com> 
> Cc: "discuss at openvswitch.org" <discuss at openvswitch.org> 
> Sent: Thursday, January 19, 2012 3:05 PM
> Subject: Re: [ovs-discuss] Is flow extraction on the critical path
> 
> Open vSwitch doesn't support OpenFlow 1.1, but, regardless, flow extraction is on the critical path.  I can't think how to avoid that, since it must classify the packets to determine which actions to apply.  It does some smart caching to make the lookup fast in software, but it still needs to extract the flow to do that lookup.
> 
> --Justin
> 
> 
> On Jan 19, 2012, at 1:27 AM, K.Kalapriya wrote:
> 
> > hi,
> > 
> > Just wanted to know if the flow extraction phase (page 9 of the openflow switch specification 1.1.0) on the critical path of the switch performance?
> > 
> > regards,
> > kalapriya.
> > _______________________________________________
> > discuss mailing list
> > discuss at openvswitch.org
> > http://openvswitch.org/mailman/listinfo/discuss
> 
> 
>