> Phil Yang <phil.y...@arm.com> writes: > > <...> > > Subject: RE: [dpdk-dev] [PATCH v3] net/mlx5: relaxed ordering for > > multi- packet RQ buffer refcnt > > > > Hi Phil Yang, we noticed that this patch gives us 10% of performance > > degradation on ARM. > > x86 seems to be unaffected though. Do you know what may be the reason > > of this behavior? > > Hi Alexander, > > Thanks for your feedback. > This patch removed some expensive memory barriers on aarch64, it should get > better performance. > I am not sure the root cause of this degradation now, I will start the > investigation. We can profiling this issue together. > Could you share your test case(including your testbed configuration) with us? > > Thanks, > Phil
I'm surprised too, Phil, but looks like it is actually making things worse. I used Connect-X 6DX on aarch64: Linux dragon71-bf 5.4.31-mlnx.15.ge938819 #1 SMP PREEMPT Thu Jul 2 17:01:15 IDT 2020 aarch64 aarch64 aarch64 GNU/Linux Traffic generator sends 60 bytes packets and DUT executes the following command: arm64-bluefield-linuxapp-gcc/build/app/test-pmd/testpmd -n 4 -w 0000:03:00.1,mprq_en=1,rxqs_min_mprq=1 -w 0000:03:00.0,mprq_en=1,rxqs_min_mprq=1 -c 0xe -- --burst=64 --mbcache=512 -i --nb-cores=1 --rxq=1 --txq=1 --txd=256 --rxd=256 --auto-start --rss-udp Without a patch I'm getting 3.2mpps, and only 2.9mpps when the patch is applied. Regards, Alex
