Re: [dpdk-dev] L3fwd mode in testpmd

[Honnappa Nagarahalli <Honnappa.Nagarahalli@arm.com>]

<snip>

> 
> > >
> > > On Tue, 27 Apr 2021 10:50:20 +0100
> > > Ferruh Yigit <ferruh.yigit@intel.com> wrote:
> > >
> > > > Agree that it may help testing to have l3fwd support on the testpmd.
> > > >
> > > > Two concerns,
> > > > 1) Testpmd already too complex.
> > > > 2) Code duplication.
> > > >
> > > > For 1), if the l3fwd can be implemented in testpmd as new,
> > > > independent forwarding mode, without touching rest of the testpmd,
> > > > I think it can be
> > > OK.
> > > >
> > > > Not sure how to address 2), also lets say we want to add new
> > > > feature to l3fwd, where it should go, to the sample or to the testpmd?
> > >
> > > The original purpose of l3fwd seems to be getting lost here.
> > > It was intended as an example, not a complete test or real life application.
> > The issue is, this app has become an industry standard for performance
> comparison between platforms (whether we like it or not).
> > But, it
> > does not have a whole lot of debugging capabilities.
> 
> Ok, could you list what exactly you think is missed?
> If we are talking about extra stats, then I still think it is probably easier to add
> it into l3fwd, then pull whole l3fwd code into test-pmd.
In stats it is missing hardware, software stats, burst stats.
From run time configuration capability, it is missing burst size, rx/tx queue depth, number of queues we can assign to a core.

> 
> > I think adding a L3fwd mode to testpmd will be helpful to keep the
> > sample application simpler.
> 
> Hmm, not sure how these 2 things are linked...
> Why let say adding fib-fwd into test-pmd will help to decrease l3fwd code
> complexity?
From my perspective, L3fwd example application should showcase how to use DPDK, various packet processing models in DPDK. Anyone new to DPDK should be able to take this code and start creating their application.
However, this application has LPM, Exact match and FIB. I am not sure how Exact Match and FIB modes help the user.
I suggest removing LPM from L3fwd example application as FIB is added (or vice versa).