[ovs-discuss] OpenVSwitch flow forwarding

Jesse Gross jesse at nicira.com
Tue Feb 7 21:21:30 UTC 2012

On Mon, Feb 6, 2012 at 9:25 PM, Masoud Moshref Javadi
<masood.moshref.j at gmail.com> wrote:
> Thanks,
> It seems that the bottleneck can be the lookup in these userspace when we
> have lots of new flows.
> My question is how many table we can have in the userspace?

I think you're confusing OpenFlow tables with unique sets of
wildcards.  The former has a limit but each one is not scanned on flow
lookup.  The later depends on the wildcards in the flows that are

> How many entry the kernel table can have?

Like I said, it is primarily restricted by userspace.

> Why did you use one table for each wildcards set, and not use tree based
> data structures like R+ - trees?

The number of bits that can be wildcarded is large but the number of
unique sets of wildcards is usually small in practice.

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