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Date: Thu, 22 Sep 2016 10:29:03 +0800
From: Yuanhan Liu <yuanhan.liu@linux.intel.com>
To: Jianbo Liu <jianbo.liu@linaro.org>
Cc: "Wang, Zhihong" <zhihong.wang@intel.com>,
 Maxime Coquelin <maxime.coquelin@redhat.com>, "dev@dpdk.org" <dev@dpdk.org>
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On Wed, Sep 21, 2016 at 08:54:11PM +0800, Jianbo Liu wrote:
> >> > My setup consists of one host running a guest.
> >> > The guest generates as much 64bytes packets as possible using
> >>
> >> Have you tested with other different packet size?
> >> My testing shows that performance is dropping when packet size is more
> >> than 256.
> >
> >
> > Hi Jianbo,
> >
> > Thanks for reporting this.
> >
> >  1. Are you running the vector frontend with mrg_rxbuf=off?
> >
> >  2. Could you please specify what CPU you're running? Is it Haswell
> >     or Ivy Bridge?
> >
> >  3. How many percentage of drop are you seeing?
> >
> > This is expected by me because I've already found the root cause and
> > the way to optimize it, but since it missed the v0 deadline and
> > requires changes in eal/memcpy, I postpone it to the next release.
> >
> > After the upcoming optimization the performance for packets larger
> > than 256 will be improved, and the new code will be much faster than
> > the current code.
> >
> 
> Sorry, I tested on an ARM server, but I wonder if there is the same
> issue for x86 platform.

Would you please provide more details? Say, answer the two left
questions from Zhihong?

Thanks.

	--yliu