rdgreenall@watnot.UUCP (Richard Greenall) (10/13/86)
<Take this line-eater!!>
I was wondering if any one out there has had any experience in running
a bulletin board system off of a 20 meg hard disk. I am wondering
if the constant running of the hard disk is damaging to it. (Ex. running
approximately 20 hours. per day.)
It seems crazy to me that the hard disk should be running
when there is no activity on the board. The
ideal situation would be for the pc to start the motor on the
hard disk as soon as it detects a call on the modem. (I think this
is impossible but who knows what somebody can come up with)
Any Ideas? Has anybody tried such a project.
Do I have any idea of what I'm talking about?
Mail any Ideas to me and then I will post them to the Net.
Thanks.
RDGREENALL@watnot.UUCP
(Richard Greenall)
timothym@tekigm2.UUCP (Timothy D Margeson) (10/15/86)
Hi,
Here in our department, we run three IBM PC-AT's. Each with two 20 meg disks.
Each are left on 24 hours a day. In each system there is one stock (CMI?)
drive, and one after market drive (Seagate). We have not had any problems
with the disks or computers, and we have had them over one year now. That
makes a total test time of 50,000 hours with 0 failures. Or 25,000 hours per
disk drive without failures. Not bad when you think about it.
BTW, it is my understanding that crashes are more likely during spin-up and
spin-down, as that is when the heads actually begin or stop flying over the
media.
FYI....
--
Tim Margeson (206)253-5240
PO Box 3500 d/s C1-937 @@ 'Who said that?'
Vancouver, WA. 98668
{allegra..inhp4..decvax..ucbvax}!tektronix!tekigm2!timothym bill@hp-pcd.UUCP (bill) (10/16/86)
I could be wrong, but it seems to me that it might be more damaging to constantly spin your hard disk up and down than it would be to just keep the thing running all the time. Don't hard disk heads generally "float" above the disk surface, rather than touch it (as is the case with floppies)? My 20M hard disk frequently runs 24 hours a day, 7 days a week, and generally runs just fine. (I say "generally" because it's a CMI drive in a PC-AT, and has a family history of hard errors.) bill frolik hp-pcd!bill Hewlett-Packard Portable Computer Division Corvallis, Oregon
brown@nicmad.UUCP (10/17/86)
In article <12068@watnot.UUCP> rdgreenall@watnot.UUCP (Richard Greenall) writes: > I was wondering if any one out there has had any experience in running >a bulletin board system off of a 20 meg hard disk. I am wondering >if the constant running of the hard disk is damaging to it. (Ex. running >approximately 20 hours. per day.) Yep! I run a BBS using a PC-XT, with two 20MB drives in it. One is for work stuff and the other for the BBS. Before that I had two 10MB drives in the XT, which ran for over a year for 24 hours a day. The current drives have only been in about 6 months. They too run for 24 hours a day. Yesterday I had to low-level format the BBS drive. The drive started to take hits, ie, it would error when reading data. Everything seems fine now. Because the drives run 24 hours a day, I use a program called TIMEPARK which parks the heads after 1 to 9 minutes (user selectable). That keeps the heads off the work area while nobody is on the system and since the work drive is spinning, it isn't accessed, it parks that one as well. I wouldn't worry about drives spinning 24 hours a day. -- ihnp4------\ harvard-\ \ Mr. Video seismo!uwvax!nicmad!brown topaz-/ / decvax------/
spellman@hplchm.HP.COM (Miles Spellman) (10/17/86)
If the disk has decent bearings its better for the disk to run continuously throughout its life, but if the manufacturer skimped on bearings thats different. It just depends what the weak link is.
randy@chinet.UUCP (Randy Suess) (10/19/86)
In article <897@nicmad.UUCP> brown@nicmad.UUCP (Mr. Video) writes: >In article <12068@watnot.UUCP> rdgreenall@watnot.UUCP (Richard Greenall) writes: >> I was wondering if any one out there has had any experience in running >>a bulletin board system off of a 20 meg hard disk. I am wondering >>if the constant running of the hard disk is damaging to it. (Ex. running >>approximately 20 hours. per day.) The original bbs, CBBS-Chicago has been running 8 years, the last 6 on a 15 meg HD in a s-100 box *continuously* but for one power outage about 3 years ago. Also, my 3b2 has been running with standard PC type 80 meg disks for over a year. I believe the general opinion is that hard disks like to run, and spinning them up and down is what leads to failures. -- .. that's the biz, sweetheart... Randy Suess chinet - Public Access UN*X (312) 545 7535 (h) (312) 283 0559 (system) ..!ihnp4!chinet!randy
dean@ruby.berkeley.edu (10/20/86)
In article <644@chinet.UUCP> randy@chinet.UUCP (Randy Suess) writes: >... I believe the general opinion is that >hard disks like to run, and spinning them up and down is what leads to >failures. And, in general, that seems to be the consensus gathering on this topic. BUT: 1) What about drives on their sides? I assume disk drives are designed to be run horizontally. Do you get problems due to the one-sided weight distribution? 2) Are there any disk drive engineers listening? You guys know what's up. What are your design objectives? Are disks designed such that it's better for them to spin indefinitely rather than being turned on and off? Is it the same story for 10Mb disks as it is for 80Mb disks, or are the design considerations different? Thanks. -Dean (dean@ruby.berkeley.edu)
davidsen@steinmetz.UUCP (Davidsen) (10/20/86)
In article <12068@watnot.UUCP> rdgreenall@watnot.UUCP (Richard Greenall) writes: > I was wondering if any one out there has had any experience in running >a bulletin board system off of a 20 meg hard disk. I am wondering >if the constant running of the hard disk is damaging to it. (Ex. running >approximately 20 hours. per day.) Actually the power up sequence is the most likely to damage you disk. When the disk is up to speed, the heads fly just off the platter and there is no wear. Most hard disks, particularly the less expensive models, have a "landing zone", which is where the heads land on the surface of the platter when powered down. Needless to say this is always a good time to have backups. We have a number of XTs where I work which have been powered up for about four years now. At one time one of the repair technicians determined that the failure rate for PCs and terminals was lower in terms of failures per calendar year with the machine left powered up all the time. Disclamer: this represents personal opinion and experience only. -- -bill davidsen seismo!rochester!steinmetz!--\ / \ ihnp4! unirot ------------->---> crdos1!davidsen \ / chinet! ---------------------/ (davidsen@ge-crd.ARPA) "Stupidity, like virtue, is its own reward"
jso@edison.UUCP (John Owens) (10/20/86)
In article <12068@watnot.UUCP>, rdgreenall@watnot.UUCP (Richard Greenall) writes: > I am wondering if the constant running of the hard disk is damaging to > it. (Ex. running approximately 20 hours. per day.) > It seems crazy to me that the hard disk should be running > when there is no activity on the board. The > ideal situation would be for the pc to start the motor on the > hard disk as soon as it detects a call on the modem. (I think this > is impossible but who knows what somebody can come up with) I can see where you are coming from, but this would be worse, for a number of reasons. 1) Although the heads contact the disk surface for floppies, for hard disks they fly above the surface of the disk, separated by a small air space. There is no wear on the surface on the disk while it is spinning or being accessed. 2) A hard disk has a lot of inertia. When you start the motor on a floppy drive, the system typically waits for a second or less for the floppy to "come up to speed". This can take up to a minute on a typical small (20MB) hard disk. Even after this amount of time, the rotational speed won't be quite as stable as it will after it has been running for a long period of time. 3) The shocks to the drive mechanism and to the disk platters themselves from slowing down, stopping, and coming back up to speed are significant. They can, after time, cause mechanical problems and can knock loose any foreign particles that might be safely tucked in a crevice somewhere. 4) Winchester-type disks are *designed* to be constantly running. On large multi-user systems, with disks up to 14" in diameter, the drives run 24 hours a day, 365 days a year, constantly; "spinning down" the disk is a rare event. When designing hard disks for microcomputers, the designers have to take into account that the disk will be powered up and down quite often (once or twice a day), and make it more rugged to withstand that. In summary, please *don't* try to start and stop your hard disk like that. And for anyone who has a system with a hard disk: don't turn it on and off many times a day if you can help it. I have an XT that I turn on and off daily, and an AT that has been running for months without being powered down. (The AT is running XENIX, and I want to leave it up at all times to pick up mail and such.) John Owens General Electric Company - Charlottesville, VA jso@edison.GE.COM old arpa: jso%edison.GE.COM@seismo.CSS.GOV +1 804 978 5726 old uucp: {seismo,decuac,houxm,calma}!edison!jso
cjdb@sphinx.UChicago.UUCP (Charles Blair) (10/21/86)
> ... I believe the general opinion is that >hard disks like to run, and spinning them up and down is what leads to >failures. >Randy Suess >chinet - Public Access UN*X >(312) 545 7535 (h) (312) 283 0559 (system) >..!ihnp4!chinet!randy I'll buy the argument that hard disks like to run, but do *PC's* like to run as well? I'd like to keep my AT running all the time, but can anyone tell me which if any other parts might go first? Is this an issue with these machines? I sure would appreciate the input, especially since my original CMI bit the dust not too long ago, and I would like to maximize the life of the replacemnet drive (Seagate). -- Charles Blair ..!ihnp4!gargoyle!sphinx!cjdb The University of Chicago lib.cb%chip@UChicago.Bitnet
lawrence@nvanbc.UUCP (10/25/86)
Request for info on running PC/AT 24hr/day from: >Charles Blair ..!ihnp4!gargoyle!sphinx!cjdb >The University of Chicago lib.cb%chip@UChicago.Bitnet I have run my PC since November 1984 with the following problems: 1) disk controller died in the 1st month 2) CMI hard drive died at 1 1/2 years (replaced with Segate) 3) Power supply died at last month. The power supply was a blown fuse I think but it was inside the shield and I left it up to XEROX (under contract) to decide how to fix it.