Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.milw.wisc.edu!lll-winken!ames!cincsac.arc.nasa.gov!medin
From: medin@cincsac.arc.nasa.gov (Milo S. Medin)
Newsgroups: comp.protocols.appletalk
Subject: Re: Ethernet vs LocalTalk
Message-ID: <25142@ames.arc.nasa.gov>
Date: 8 May 89 23:45:31 GMT
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Well, I can certainly blast out bits through a hyperchannel a lot
faster than pumping useful data through it.  Many pieces of hardware
deal with more small packets much worse than few large packets.
Things like setting up DMA, dealing with interrupts, or
polling interfaces and such.  In general, there are 2 costs involved
in protocol processing.  One is fixed per message unit size, and
the other is variable with the size.  Hardware issues can affect
both.  I'll give hyperchannel as a straightforward example.  

					Thanks,
					   Milo

PS A standard performance of 2.2 Mbits/sec throughput isn't that bad,
but it's far from 9 Mbits/sec, which is the point I was trying
to make.