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Date:   Thu, 29 Sep 2022 17:19:33 +0200
From:   Andrew Lunn <andrew@lunn.ch>
To:     Shenwei Wang <shenwei.wang@nxp.com>
Cc:     Joakim Zhang <qiangqing.zhang@nxp.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Jesper Dangaard Brouer <hawk@kernel.org>,
        John Fastabend <john.fastabend@gmail.com>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "imx@lists.linux.dev" <imx@lists.linux.dev>
Subject: Re: [EXT] Re: [PATCH 1/1] net: fec: add initial XDP support
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> > > I actually did some compare testing regarding the page pool for normal
> > > traffic.  So far I don't see significant improvement in the current
> > > implementation. The performance for large packets improves a little,
> > > and the performance for small packets get a little worse.
> > 
> > What hardware was this for? imx51? imx6? imx7 Vybrid? These all use the FEC.
> 
> I tested on imx8qxp platform. It is ARM64.

Please also test the older platforms. imx8 is quite powerful, so some
performance loss does not matter too much. But for the older systems,
i know people has spent a lot of time and effort optimising network
performance, and they will be unhappy if you make it slower.

> > By small packets, do you mean those under the copybreak limit?
> > 
> > Please provide some benchmark numbers with your next patchset.
> 

> Yes, the packet size is 64 bytes and it is under the copybreak
> limit. As the impact is not significant, I would prefer to remove
> the copybreak logic.

Lets look at the benchmark numbers, what you actually mean by not
significant, and across a range of hardware.

	     Andrew