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Apparently, though unproven, at 23:00 on Wednesday 22 September 2010, walt did |
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opine thusly: |
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> On 09/22/2010 01:26 PM, Stroller wrote: |
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> > On 22 Sep 2010, at 17:46, Grant wrote: |
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> >> ... I noticed some errors when I was cp -ax'ing everything |
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> >> from my old drive to the new drive which were accompanied by loud |
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> >> clicks. Is there a way to do a comprehensive test/check of the old |
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> >> drive to see if it has any problems? |
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> > |
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> > You don't need to do a test. The disk that is making the noises is |
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> > f**ked. |
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> > |
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> > Assuming that it's the old drive that is knackered... |
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> |
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> I was thinking the same. In the past three or four years I've had more |
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> brand new drives go bad than older ones. Funny, though, the replacement |
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> drives I've received under warranty work spectacularly well. Just luck? |
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No, not luck. It's a numbers game and that how the dice roll. |
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Modern drives are complex. As such they are more likely to fail than ancient |
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drives simply because of the complexity. They are also better engineered than |
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old ones but the loss from complexity is greater than the game from better |
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engineering. Plus, they are incredibly cheap compared to ancient times. |
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Engineered products all have characteristic failure rates common across the |
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model, the infamous bathtub curve. The factory can't do the full range of |
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nurn-in tests they'd like to (bean counters rule), so you get a drive at the |
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later end of the bathtub. Hence, you see elevated failure rates. The factory |
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is willing to take a financial knock here as the loss from a few replacements |
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is much lower than the gigantic loss from fully and properly testing every |
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drive for hours and hours. |
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You get a replacement. Simple odds are that it is not one of the few that will |
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fail early, so it doesn't and you think "Wow! The gods like me." Nope, |
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statistics like me. |
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If the factory was real smart, they would keep a small stock of fully tested |
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drives on the replacement shelf, only to be released as under-warranty |
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replacements. You'd be certain these drives would NOT fail and it's trivially |
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easy to get this past the bean counters because you'd be winning back customer |
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loyalty. And the cost of testing those few drives fully is not that much. The |
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average bean counter has a ballistic orgasm at the thought of this, and yes |
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they can even tell you the price they attach to winning back that loyalty. |
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So now you know. Accountants do not think like techies. |
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-- |
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alan dot mckinnon at gmail dot com |
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