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.
> 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
