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- Path: sparky!uunet!elroy.jpl.nasa.gov!nntp-server.caltech.edu!SOL1.GPS.CALTECH.EDU!CARL
- From: carl@SOL1.GPS.CALTECH.EDU (Carl J Lydick)
- Newsgroups: comp.os.vms
- Subject: Re: computers, automobiles (and bignums)
- Date: 26 Jan 1993 06:01:35 GMT
- Organization: HST Wide Field/Planetary Camera
- Lines: 26
- Distribution: world
- Message-ID: <1k2k3vINNs62@gap.caltech.edu>
- References: <20A01C28_00075948.009672328175A320$92_3@UK.AC.KCL.PH.IPG>
- Reply-To: carl@SOL1.GPS.CALTECH.EDU
- NNTP-Posting-Host: sol1.gps.caltech.edu
-
- In article <20A01C28_00075948.009672328175A320$92_3@UK.AC.KCL.PH.IPG>, SYSMGR@IPG.PH.KCL.AC.UK writes:
- >I don't know how often 1960-era computers crashed, but I'd be surprised if
- >it was less often than current ones and I'd guess 10-100 times less often
- >which would make the Roller as safe as a train.
-
- In that case, I suppose you're very easily-surprised. MTBF for many computers
- of the early '60s was on the order of 4 hours. *THEN* you'd have to spend
- hours tracking down the failed tube. Aren't they teaching history in the
- schools any more? The transistor was invented in the late '50s. Tube
- computers were still quite common in the early '60s. Now, let's see. A
- computer from the early '60s could run for four hours before a crash. For
- computers today, you shouldn't expect crashes more often than once every for
- months. 24 hours per day, 30 days per month, means we've got an improvement of
- at least 720. The improvement factor is more like 1000 than the 100 you so
- reluctantly allow into consideration.
-
- If your computer crashes more often than about 3 times a year, you're probably
- running a UNIX system.
- --------------------------------------------------------------------------------
- Carl J Lydick | INTERnet: CARL@SOL1.GPS.CALTECH.EDU | NSI/HEPnet: SOL1::CARL
-
- Disclaimer: Hey, I understand VAXen and VMS. That's what I get paid for. My
- understanding of astronomy is purely at the amateur level (or below). So
- unless what I'm saying is directly related to VAX/VMS, don't hold me or my
- organization responsible for it. If it IS related to VAX/VMS, you can try to
- hold me responsible for it, but my organization had nothing to do with it.
-