Re: [Hampshire] [OT] MTBF

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Author: Hugo Mills
Date:  
To: Hampshire LUG Discussion List
Subject: Re: [Hampshire] [OT] MTBF

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On Sat, Jul 18, 2009 at 10:44:49PM +0100, James Courtier-Dutton wrote:
> Hi,
>
> Take an example of a SSD
> Manufacturer quotes:
> OCZ-120GB-Solid-State-Drive: MTBF 1.5 million hours.
> To me that means and MTBF of 171 years abouts.
> So, why do OCZ only guarantee it for 2 years?


Look instead at the BER -- the bit error rate. This is the number
of bits that you can expect to read from the device between
unrecoverable media errors (whether justified by a genuine damaged
piece of media or not). Then compare that with the workload of
the device. Consider also the implications of rebuilding a RAID array
on a set of devices with that BER.

Hugo.

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