Reasonable prior distribution from the original data – which works here as Problem in baseball where he takes an empirical Bayes Library ( dplyr, nflicts = FALSE ) hdds % tibble :: as_tibble () %>% select ( mfg = MFR, name = Models, size = Drive.Size, days = Drive.Days, failures = Drive.Failures ) %>% mutate ( name = trimws ( gsub ( ",", "", name, fixed = TRUE )), days = as.integer ( gsub ( ",", "", days, fixed = TRUE )), failures = as.integer ( gsub ( ",", "", failures, fixed = TRUE )) ) %>% bind_rows ( omitted ) %>% mutate ( # Compute BackBlaze's "Annualized Failure Rate". Re-estimating Failure Rates using Empirical Bayesįirst, we can extract the data that is missing from the table but mentioned in Prior expectation of the failure rate (which might be close to the historicalĪverage across all drives) with observed failure events to produce a moreĪccurate estimate for each model. This looks like a perfect use case for a Bayesian approach: we want to combine a Text of the article and available in their public datasets). Less than 5,000 days of operation in Q4 2019 (although they are detailed in the
The authors are sensitive to this possibility and suppress data from drives with This might lead us to question the accuracy for smaller samples in fact, Uses simple averages to compute the “Annualized Failure Rate” (AFR), despite theįact that the actual count data vary by orders of magnitude, down to a singleĭigit. One of the things that strikes me about the presentation above is that BackBlaze They’re also notable as the only large public Its hundreds of thousands of hard drives, most recently on Februaryįailure rate of different models can vary widely, these posts sometimes make a The company received these specific drives as warranty replacements, so they were probably refurbished with wear and tear on them by the time they met Backblaze’s HDD taskmasters.A Bayesian Estimate of BackBlaze's Hard Drive Failure RatesĮach quarter the backup service BackBlaze publishes data on the failure rate of Ouch!īackblaze said this particular model is pretty bad, but it cautions not to read too much into it. The worst of the bunch, meanwhile was the 1.5 TB Seagate Barracuda Green (ST1500DL003), with an average lifespan of 0.8 years.
#Backblaze blog hard drive Pc
(Remember, these drives are putting in some serious overtime that your PC would likely never see.) That model was followed by another Hitachi, the Deskstar 5K3000 (HDS5C3030ALA630) with an average lifetime of 1.7 years and a similar failure rate. Earning impressive marks for reliability was the Hitachi 3TB Deskstar 7K3000 (HDS723030ALA640) with a 0.9 percent failure rate and an average lifetime of about 2.1 years. Failure rates Backblazeįor this report, Backblaze took a look at 15 different HDD models from the three aforementioned major brands. Here’s a quick look at the highlights from the company’s HDD breakdown.
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