From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Monjalon <thomas@monjalon.net>
Subject: Re: [PATCH v8 1/3] eal/x86: run-time dispatch over memcpy
Date: Thu, 02 Nov 2017 11:44:34 +0100
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Cc: dev@dpdk.org, "Richardson, Bruce" <bruce.richardson@intel.com>, "Ananyev,
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To: "Wang, Zhihong" <zhihong.wang@intel.com>, "Li,
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02/11/2017 11:22, Wang, Zhihong:
> > I don't know what is creating this drop exactly.
> > When doing different tests on different environments, we do not see this
> > drop.
> > If nobody else can see such issue, I guess we can ignore it.
> 
> Hi Thomas, Xiaoyun,
> 
> With this patch (commit 84cc318424d49372dd2a5fbf3cf84426bf95acce) I see
> more than 20% performance drop in vhost loopback test with testpmd
> macswap for 256 bytes packets, which means it impacts actual vSwitching
> performance.
> 
> Suggest we fix it or revert it for this release.

I think we need more numbers to take a decision.
What is the benefit of this patch? In which use-cases?
What are the drawbacks? In which use-cases?

Please, it is a call to test performance with and without this patch
in more environments (CPU, packet size, applications).