Re: high performance ethernet and alpha architecture

[Greg Lindahl <lindahl cs virginia edu>]

> the following comment:
> 
>     I have removed the buffer copies needed for receive on Intels.  I cannot
>     remove them for   Alphas since  the  Tulip hardware   only does longword
>     aligned  DMA transfers  and  the  Alphas get   alignment traps with  non
>     longword aligned data copies (which makes them really slow). No comment.

I believe that this is an issue with tulips on the alpha, in Becker's
driver too. However, remember that memcopy speed is much, much higher
than 100 megabits. So I'd suggest testing with your actual app before
you conclude this is a show-stopper. [ At gigabit, it is a significant
performance hit for codes that really want all that bandwidth. ]

You mentioned 4-port cards. If you expect to be able to get more than
100 mbits with your application at any one time, I'd suggest testing
first.

-- greg