ross@mscf.med.upenn.edu (11/15/89)
I am currently managing a PC with an 80 meg hard drive that is used as
a file server. This machine is generally in use for about 7 hrs per day.
The machine is a PC clone.
The question is: Is it best to leave this machine on constantly or is it
better to park the diskheads at the end of the workday and power the
machine off.
What are some advantages and disadvantages. I would suspect that if the
machine is left on, the disk is still spinning with the heads positioned
in the position of last access (probably that valuable database file
that everybody accesses all the time).
I ask because this machine has never been powered down and after only
4 months of use has experienced some major hard disk problems which
required complete reformatting.
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Also, does anybody know if the hard drive heads move periodically on
the IBM PS/2. I notice that about every 15 minutes if I am not using
the hard drive, the light goes on and the drive is doing something
(but what?)
Thanks for your assistance.
--
--- Andy Ross ---
University of Pennsylvania
Medical School Computer Facilityspolsky-joel@CS.YALE.EDU (Joel Spolsky) (11/17/89)
In article <165@mscf.med.upenn.edu> ross@mscf.med.upenn.edu writes: | |The question is: Is it best to leave this machine on constantly or is it | better to park the diskheads at the end of the workday and power the | machine off. This comes up all the time. The conclusion is that it is best to keep the thing on because the strain on the circuits is greatest at power-on, indeed, IBM internally rates PC's as having a mean time between failures of n power-ups +/- 100% where n is some large number, I think 10,000 for the original IBM/PC. The idea is that MTBF is a function of how often you turn the thing on/off. You can park the heads at the end of the day if you want, and you should blank the screen or switch that off to prevent etching. +----------------+----------------------------------------------------------+ | Joel Spolsky | bitnet: spolsky@yalecs.bitnet uucp: ...!yale!spolsky | | | internet: spolsky@cs.yale.edu voicenet: 203-436-1538 | +----------------+----------------------------------------------------------+ #include <disclaimer.h>