Gianfar is slower than fcc_enet on MPC8541 ???

[Pantelis Antoniou]

Can you provide some more information?

Actual timings, and a tcpdump fragment?

On 2/14/06, Laurent Lagrange <lagrange at fr.oleane.com> wrote:
>
> Hi Pantelis,
>
> Thanks for the express reply.
>
> I know that what I say seems incredible. But I don't understand what NAPI
> does.
> My measure is very simple. I display a message on the client when 1000
> exchanges are done.
> I already check the ifconfig stats on the board after some seconds.
> The measures seems the same with or without NAPI.
>
> More details ?
> Thanks again
> Laurent
>
>
>
> -----Message d'origine-----
> *De :* Pantelis Antoniou [mailto:pantelis.antoniou at gmail.com]
> *Envoyé :* mar. 14 février 2006 16:29
> *À :* Laurent Lagrange
> *Cc :* linuxppc-embedded at ozlabs.org
> *Objet :* Re: Gianfar is slower than fcc_enet on MPC8541 ???
>
> Hi Laurent,
>
> I found that pretty hard to believe.
>
> What are you measuring exactly?
>
> Speed of replies? If so it's explainable since the TSECs use
> NAPI.
>
> Regards
>
> Pantelis
>
> On 2/14/06, Laurent Lagrange <lagrange at fr.oleane.com> wrote:
> >
> >
> > Hello,
> >
> > I work on a cutom MPC8541 board with Linux 2.6.9.
> > The kernel activates the L1 cache (instructions and data)
> > and the L2 cache (entirely used as cache and not as sram).
> >
> > I configure
> > 1 FCC (FCC1),
> > 2 TSECs with or without NAPI (no effect) but without stashing in L2
> > sram.
> > All PHYs are automatically configured in 100MB full duplex.
> >
> >         eth0: Gianfar Ethernet Controller Version 1.1, 00:10:cd:48:48:e0
> >         eth0: Running with NAPI disabled
> >         eth0: 64/64 RX/TX BD ring size
> >         eth1: Gianfar Ethernet Controller Version 1.1, 00:10:cd:48:48:e1
> >         eth1: Running with NAPI disabled
> >         eth1: 64/64 RX/TX BD ring size
> >         eth2: FCC ENET Version custom, 00:10:cd:48:48:e2
> >
> > Then I launch 3 simple TCP servers, one on each ports.
> >
> > From remote machines I runs 3 TCP clients.
> > The client sends messages of 1000 bytes,
> > The server receives and echoes the message
> > The client receives the echoed message, check the content
> > and sends a new message again.
> >
> > The result is that the 2 TSECs are 2 times slower than the FCC.
> >
> > If I run a "top" application on the board, I use less than 10% of the
> > CPU
> > Each port consumes about 1/3 of the CPU.
> >
> > Any idea on how to configure the gianfar driver ?
> >
> > Thanks
> > Laurent
> >
> >
> > _______________________________________________
> > Linuxppc-embedded mailing list
> > Linuxppc-embedded at ozlabs.org
> > https://ozlabs.org/mailman/listinfo/linuxppc-embedded
> >
>
>
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