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From: werme@Alliant.COM (Ric Werme)
Newsgroups: comp.dcom.lans
Subject: Ethernet chip performance request
Message-ID: <4467@alliant.Alliant.COM>
Date: 4 Feb 91 18:57:29 GMT
Organization: Alliant Computer Systems Corp.
Lines: 25

I recently got a BSD driver for Rockwell/CMC's CMC-130 Ethernet board running
at 1.1 MB/sec for UDP data and 0.8 MB/sec for TCP.  (If I get a chance, I'll
work on the latter some.)  So far we haven't run into any problems talking to
systems that can't handle the minimal delay between packets.  However,
Van Jacobson's reports of problems with Intel 82586 performance leaves me
worried about other systems our customers may hookup.  Also, I think it was
here that some people described a PC system that needed substantial delays
between IP fragments.

So, I'd appreciate hearing from anyone with experience with Ethernet chips
from National Semi, the 32 bit LANCE (I forget its name), and any other
chip set about how fast they can receive data.  We might as well discuss
any problems people have run into with sending data in case customers call
up and grumble about only being able to get 500 KB/sec from their FOOBAR/X000
box to us.

BTW, the CMC-130 is a pretty solid beast. I've found 4 or 5 bugs in the
firmware, all of which will be fixed in their next PROM spin.  The board
transfers data at about 27 MB/sec over the VME bus so it leaves plenty of
bandwidth for slower devices (like disk controllers...).
-- 

| A pride of lions              | Eric J Werme                   |
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