Xref: utzoo comp.sys.ibm.pc:51384 comp.os.minix:10911 comp.unix.xenix:11773 Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!samsung!zaphod.mps.ohio-state.edu!usc!apple!voder!nsc!amdahl!rtech!wrs!hwajin From: hwajin@wrs.wrs.com (Hwa Jin Bae) Newsgroups: comp.sys.ibm.pc,comp.os.minix,comp.unix.xenix Subject: Ethernet math (Was Re: MWC's Coherent - A Lemon...) Message-ID: <1077@wrs.wrs.com> Date: 28 May 90 17:30:08 GMT References: <2841@crash.cts.com> Reply-To: hwajin@wrs.wrs.com (Hwa Jin Bae) Followup-To: comp.sys.ibm.pc Organization: Wind River Systems, Emeryville, CA Lines: 55 In article <2841@crash.cts.com> jca@pnet01.cts.com (John C. Archambeau) writes: >Anything can affect the throughput of an ethernet. If one machine that is >part of the network chatter is not up to the speed in processing data (i.e. a >slow ethernet card) then it can and often times will affect the through put of >the entire network. Overload the Appletalk/ethernet gateway with a large >number of Macs telnet'ing into one or more Suns and that will slow things down >well since the gateway has to service all of these Macs as well as handle all >of the ethernet traffic going into the Appletalk network. Duh. Tell me something new. Is it just me or are you trying to change the story here? The story being: In article <2755@crash.cts.com> jca@pnet01.cts.com (John C. Archambeau) writes: > Yes, but that's a quiet ethernet. What I'm referring to is a real noisy > ethernet that is being used. > Let me setup a real network of the order of 10+ machines with varying > performance on the ethernet and I will bet that the performance will be about > 3 Mbit per second on a good day. Where I replied: Not true at all. Even with "a real network" I have here with 30+ various sun workstations (sparcStations, 3/60's, etc.) and servers (plenty of NFS traffic), burst throughput performance of around 600 MegBytes/sec can be sustained without causing meltdowns. This is using severly hacked version of 4.3 BSD Tahoe TCP/IP running within our realtime OS on a 16Mhz 68020 VME SBC with an onboard LANCE chip. Now you say: > >The issue is that a lot of things can happen that will make ethernet slower >than molasses and it can be in either hardware or software. > >I've found that from experience that Macs and PC's are the biggest offenders >to mucking up ethernet throughput. Duh. What a revelation! Which point are you trying to make? Let me help: Your point #1: a "real" ethernet with more than 10 machines will have at most 3Mbit/sec performance rate on a good day. --- My data indicates this is wrong. Give me some of your data that proves otherwise. No rhetorics, please. Your point #2: Ethernet throughput varies and can be affected by ill-behaved hosts. --- What a brilliant analysis! Gee... I'd have never guessed that. Do you see a smooth transition from Point #1 to Point #2? I don't. This is getting boring, quick. Enough from me. Carry on JCA. -- hwajin@daahoud.wrs.com