Re: RAID

[lordSauron <lordsauronthegreat@gmail.com>]

On 11/10/05, Corey Hickey <bugfood-ml@fatooh.org> wrote:
> lordSauron wrote:
> > True...  makes me wonder about the frequency of drive faliures.  Those
> > who have experience: how often does that happen?  I've never had a
> > drive fail in my life, but I'm your normal desktop user so my PC is
> > off for about 8-16 hours a day.
>
> It might actually be more stressful on a hard drive to power it on and
> off once per day than it would be to just leave it on 24/7. Accelerating
> the platters requires a lot more work from the motor than simply
> maintaining constant velocity.

You've got a valid point, however, in a PC that doesn't have proper
cooling, continuous operation could become very fatal to the drive's
health.  I love my massive ATX full tower because of the good airflow
I can get through it (I built it myself - the fans suck air through
the front grille and shove the hot out the back) and the large volume
of the case allows for easier heat dissapation into the air...

All the drive failures I've heard of were for drives that were always
on, save one that was in a PC that had almost no cooling whatsoever. 
That's where my concerns come from.

> Compared to constant operation, it would certainly be worse to turn a
> hard drive on and off with a period of one minute, and it would be
> better with a period of one year; I just don't know know at what point
> on the continuum once per day lies. Is it better or worse? Since this
> thread is somewhat off-topic anyway, does anyone care to venture a guess?

Things tend to break in a chage of state.  The shuttle never blows up
while orbiting; it's only during takeoff or landing.  Hard drives - to
the best of my knowledge - die either at startup (since shutdown is a
piece of cake - retract the heads and let the platters spin down,
right?) and when temperature wears down their sensitive construction,
and I've heard of a few problems with altitude (there was a case of an
observatory being limited to a handful of drives since the others seal
wasn't really airtight - just think of heads skidding across the disks
due to insufficient air to float the heads).

Both sound like a prime time for the drives to fail, though it sounds
like the first - startup and shutdown - aren't really applicative to
me, since I turn my box on once per day and then leave it there for a
few hours until I stop for the night.  Heating is a problem I monitor
somewhat carefully - I'm not nuerotic about it, but I don't turn a
blind eye either.

> 4. Toshiba 40GB 4200RPM laptop drive. When I bought a used laptop I
> figured I'd have to replace the hard drive. A month later I got
> DriveReady SeekComplete errors. Over a few days, the errors got more and
> more frequent.

IMHO, laptop HDDs are prime targets for drive failures.  Due to
battery power constraints they're turned on and off more often than
any other type of drive, and they have to deal with a lot more
enviormental monkey business than your average box-on-the-desk.  Think
about airplanes, sudden jolts... the list just goes on and on...  it's
a wonder they don't break more often!

> In all, that's about 1/8 of all the drives I've owned or operated. I've
> also seen 5 or 6 other people's hard drives fail. 3 of those were IBM
> Deathstar 60GXPs.

he he he... your typo was funny.

I currently run off of an IBM DeskStar 27.x gig HDD, though I hope to
do away with it soon with new SATA drives to take advantage of the
faster nature of SATA150 technology.

To me it also sounds like Linux is slightly more demanding of the
drives than is windows.  Then again, I will never go back from Samba -
I actually got to *use* *all* of the 100 Mbps in my network for the
first time!  It was beautiful...  600 megs in ~15 seconds... <tear> 
Linux actually uses the system resources.  It's no wonder why ~50% of
all servers run linux - nothing else is cost-effective!

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