Hi, yuanhan: > -----Original Message----- > From: Yuanhan Liu [mailto:yuanhan....@linux.intel.com] > Sent: Wednesday, December 7, 2016 5:38 PM > To: Yang, Zhiyong <zhiyong.y...@intel.com> > Cc: Maxime Coquelin <maxime.coque...@redhat.com>; dev@dpdk.org; > Richardson, Bruce <bruce.richard...@intel.com>; Ananyev, Konstantin > <konstantin.anan...@intel.com>; Pierre Pfister (ppfister) > <ppfis...@cisco.com> > Subject: Re: [dpdk-dev] [PATCH 0/4] eal/common: introduce rte_memset > and related test > > On Wed, Dec 07, 2016 at 09:28:17AM +0000, Yang, Zhiyong wrote: > > > >> Wouldn't be worth to also use rte_memset in Virtio PMD (not > > > >> compiled/tested)? : > > > >> > > > > > > > > I think rte_memset maybe can bring some benefit here, but , I'm > > > > not clear how to enter the branch and test it. :) > > > > > > Indeed, you will need Pierre's patch: > > > [dpdk-dev] [PATCH] virtio: tx with can_push when VERSION_1 is set > > I will apply it shortly. > > > > Thanks, > > > Maxime > > > > > > Thank you Maxime. > > I can see a little, but not obviously performance improvement here. > > Are you you have run into that code piece? FYI, you have to enable virtio 1.0 > explicitly, which is disabled by deafault.
Yes. I use the patch from Pierre and set offload = 0 ; Thanks Zhiyong > > > You know, memset(hdr, 0, head_size); only consumes fewer cycles for > virtio pmd. > > head_size only 10 or 12 bytes. > > I optimize rte_memset perf further for N=8~15 bytes. > > The main purpose of Introducing rte_memset is that we can use it to > > avoid perf drop issue instead of glibc memset on some platform, I think. > > For this case (as well as the 4th patch), it's more about making sure > rte_memset is inlined. > > --yliu
