On Thu, 8 Feb 2001, Donald Becker wrote:
> > Or we can just tell people, "hey, don't use this 64-bit PCI card on a real
> > 64-bit system, it's broken by design"? I don't think that's a good
> > solution either.
>
> This is not a 64 bit PCI issue.
I know. It was just an ironic comment: we have a card with a 64-bit PCI
bus, we have a 64-bit system which very likely has some 64-bit PCI slots
on its motherboard, perfect match, right? Well, au contraire, the
performance is going to suck big-time, at least for Rx.
> It is an issue with the protocol
> stack. The IP protocol handling code must expect that the header words
> will be misaligned in some circumstances.
I won't get into this...
> It's amusing that a full receive copy is added without any concern, in
> the same discussion where zero-copy transmit is treated as a holy grail!
Amusing? Maybe. Zerocopy will still help with Tx, and with Rx we're just
trying to contain the damage, *with the existent stack*.
> This might be a transceiver preamble issue with the specific
> transceivers on the recent cards. Debugging this type of problem
> sometimes requires a D-Oscope on the MII data pins.
>
> Normally I would suspect a timing problem with a very fast machine, but
> the Starfire hardware generates its own preamble and clock signals, not
> the driver code.
See my previous mail. It turned out to be just a confused chipset.
Thanks,
Ion
--
It is better to keep your mouth shut and be thought a fool,
than to open it and remove all doubt.
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This archive was generated by hypermail 2b29 : Thu Feb 15 2001 - 21:00:13 EST