From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tiwei Bie <tiwei.bie@intel.com>
Subject: Re: [PATCH v2] vhost: adaptively batch small guest
 memory copies
Date: Mon, 11 Sep 2017 09:27:27 +0800
Message-ID: <20170911012726.GA25709@debian-ZGViaWFuCg>
References: <20170824021939.21306-1-tiwei.bie@intel.com>
 <20170908125046.28739-1-tiwei.bie@intel.com>
 <8f9831eb-3673-fb6a-06c0-702c1d0e9d96@caviumnetworks.com>
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Cc: dev@dpdk.org, yliu@fridaylinux.org, maxime.coquelin@redhat.com,
 Zhihong Wang <zhihong.wang@intel.com>,
 Zhiyong Yang <zhiyong.yang@intel.com>
To: santosh <santosh.shukla@caviumnetworks.com>
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On Sat, Sep 09, 2017 at 08:28:57PM +0530, santosh wrote:
> On Friday 08 September 2017 06:20 PM, Tiwei Bie wrote:
> > This patch adaptively batches the small guest memory copies.
> > By batching the small copies, the efficiency of executing the
> > memory LOAD instructions can be improved greatly, because the
> > memory LOAD latency can be effectively hidden by the pipeline.
> > We saw great performance boosts for small packets PVP test.
> >
> > This patch improves the performance for small packets, and has
> > distinguished the packets by size. So although the performance
> > for big packets doesn't change, it makes it relatively easy to
> > do some special optimizations for the big packets too.
> >
> > Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
> > Signed-off-by: Zhihong Wang <zhihong.wang@intel.com>
> > Signed-off-by: Zhiyong Yang <zhiyong.yang@intel.com>
> > Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
> > ---
> > This optimization depends on the CPU internal pipeline design.
> > So further tests (e.g. ARM) from the community is appreciated.
> >
> > v2: s/burst_copy/batch_copy/g
> 
> In pvp setup for arm64 platform, no performance drop noticed with this patch but no significant performance gain either. Tested-by: Santosh Shukla <santosh.shukla@caviumnetworks.com>
> 

Thank you very much for testing this patch!

Best regards,
Tiwei Bie