Sorry for calling it MBTF, but it makes me unhappy thinking about it.Originally posted by jandregg
John, if you meant MTBF it stands for mean time between failures.
What is a puzzle is that the observed MTBF is a factor of 1000 lower than the published number of 1M+ hr for a set of 80 recent disks, not all bought at the same time from the same supplier. Makes me think the MTBF figure is bogus. If one should expect 5/80 = 6% of disks to fail within 1000 hours, this would have a curious implication for PC users who typically don't use redundant configurations and for the disk manufacturer, one of the few left in the US.
John
"The following reliability specifications assume correct host/drive operational interface, including all interface timings, power supply voltages, environmental requirements and drive mounting constraints (see Section 8.4).
Seek Errors Less than 10 in 10**8 seeks
Read Error Rates [1]
Recovered Data Less than 10 errors in 10**12 bits transferred (OEM default settings)
Unrecovered Data Less than 1 sector in 10**15 bits transferred (OEM default settings)
Miscorrected Data Less than 1 sector in 10**21 bits transferred
MTBF 1,200,000 hours
Service Life 5 years
Preventive Maintenance None required
[1] Error rate specified with automatic retries and data correction with ECC enabled and all flaws reallocated."
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