[mythtv-users] The Bigger... Disk contest, Fall 2007 edition

[f-myth-users at media.mit.edu]

    > Date: Thu, 18 Oct 2007 15:51:30 -0400
    > From: "Jay R. Ashworth" <jra at baylink.com>

    > I will read it tonight.  If it doesn't mention duty cycle, I will
    > ignore it.  :-)

Remember that there may well be FAR more vendor-to-vendor variation
than there is in ATA-to-SCSI variation.  Here's an anecdote (meaning
it's NOT data):

My Series 1 TiVo.  Its A drive moves the head constantly 'cause it's
buffering the last 30m of video no matter what.  It burned out Maxtor
after Maxtor, typically within 6 months of installation.  (The B drive
burned out more slowly, but also failed.)  Each one would fail with
the "click of death", though typically only on a small range of
sectors; I was always able to DD to a new drive and recover.  [And,
of course, the original Quantum drives it came with presumably did
-not- have this bad behavior or TiVo would be bankrupt today.]

After replacing one drive four times and the other one twice, within
a span of about 3 years, I put Seagates in it.  It's been years and
neither has ever failed.  Yes, both the Maxtors and Seagates were
theoretically rated for 24x7 operation, etc etc.  Obviously both are
ATA.  Obviously, there's more to the story.  (None of them were
"AV-rated" drives or anything fancy; they were essentially the
cheapest drive of the given capacity available from either vendor.)

During that interval, I also had a Maxtor in a desktop that simply
spun 99% of the time and was in active use a few minutes a day, hence
it moved its head only a few minutes a day.  It died, TOO, just
sitting there spinning, with the click of death, so while duty cycle
certainly -accelerated- the failures -I- saw, in -my- environment, it
wasn't the whole story; the baseline failure rate with almost zero use
was still so fast that the drives failed within their first year or
two of operation.  I won't use Maxtors again in anything.  I currently
have -far- more Seagates in service than I ever had Maxtors, and I've
never had one fail.  Yes, there have since been various mergers of
companies and product lines; in particular, some "Seagate" drives are
now made by what used to be Maxtor.  Uh oh...  But what this also
means is that lore and old-wive's-tales from years ago are unlikely
to be correct -now-, so you need to heavily discount the "accepted
wisdom" that dates from 10 years ago and look at failure rates of the
drives you're buying -today-.