[rescue] Re: Fast Ethernet vs. SS2

[Greg A. Woods]

[ On Monday, November 11, 2002 at 18:42:37 (-0600), Mike Hebel wrote: ]
> Subject: Re: [rescue] Re: Fast Ethernet vs. SS2
>
> Since the card is faster than the SBUS on the output it is idle a fair 
> amount of the time.  It can pass the networking data off the bus faster 
> and thus free the bus up quicker than the existing 10mb circuits.  Thus 
> the SBUS isn't tied up with extra cycles waiting for the data to go out. 
>   Thus less overall system load where networking is concerned.

I don't know about that -- it would depend a great deal on the driver.

It also doesn't quite make sense.  Most drivers already send packets to
the ethernet interface at bus speeds -- the IF then buffers them out to
the wire.

I don't think even NetBSD offloads CPU work to the hme yet, does it?  I
don't see anything in the CVS logs.  I do see that some direct DMA
changes going in and then being backed out again....  (it does DMA, but
not direct to/from MBUFs I think).

-- 
								Greg A. Woods

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