Re: [dpdk-dev] [PATCH 4/4] examples/l3fwd: make data struct to be memory efficient

["Walsh, Conor" <conor.walsh@intel.com>]

<snip>
> >> There are some holes in data struct lcore_conf. The holes are
> >> due to alignment requirement.
> >>
> >> For struct lcore_rx_queue, there is no need to make every element
> >> of this type to be cache line aligned, because the data is not
> >> shared between cores.
> >>
> >> Member len of struct mbuf_table can be moved out. So data can be
> >> packed and there will be no need to load an extra cache line when
> >> mbuf table is empty.
> >>
> >> The change showed slight performance improvement on N1SDP platform.
> >>
> >> Suggested-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
> >>
> >> Signed-off-by: Ruifeng Wang <ruifeng.wang@arm.com>
> > This change alone is OK in the octeontx2 platform.(No difference in
> performance)
> > combining with 3/4 shows some regression. Probably is due to prefetch
> > or 128B cache line tuning specifics.
> 
> We checked it on Layerscape LS2088A platform. No difference for 1-2 core
> case. However observing ~2% regression for 4-8 cores.
> 
> Regards,
> 
> Hemant
> 

Hi Ruifeng,

l3fwd will no longer build with this patch as you have changed a struct used by the FIB lookup method.
This patch will need to be updated to also update the FIB lookup method as you have done with EM and LPM.

Thanks,
Conor.