Recently, storage service provider BackBlaze
compiled data from April 2013 to March 2022, summarizing four capacities of 4TB, 8TB, 12TB, and 14TB, as well as a variety of hard drives from Hitachi, Seagate, Toshiba, and Western Digital. The reliability of these drives is demonstrated by generating Kaplan-Meier curves.
In terms of 4TB capacity, BackBlaze selected Seagate’s ST4000DM000 and Hitachi’s HMS5C4040BLE640. The former has a total of 18,495 blocks, and the number of failures is 4,581. The annual failure rate is 2.45%, and the reliability is only about 81% after six years. The latter has a total of 12,728 blocks, with 343 failures, an annual failure rate of 0.40%, and reliability of about 97% after six years.
The reliability of Seagate’s hard drives will drop significantly within 72 months. During the same period, the number of Seagate hard drives replaced is about 4,200 more than Hitachi’s hard drives, with an average of about 700 pieces per year. However, the cost factor must also be considered. The two manufacturers have different focuses. Hitachi’s products are more geared to the enterprise market and generally have higher reliability. Of course, the average price will also be higher.
In terms of 8TB capacity, both hard drives are from Seagate
, namely ST8000DM002 and ST8000NM0055. The difference is that the former is a consumer-grade product and the latter is an enterprise-grade product. Somewhat unexpectedly, the consumer-grade product performed better than the enterprise-grade product, with annual failure rates of 1.13% and 1.35%, respectively, and 95% and 93.6% reliability over the data analysis period.
There are three hard drives in the 12TB capacity, Hitachi’s HUH721212ALN604, Seagate’s ST12000NM001G, and ST12000NM0008. These enterprise-class hard drives have a five-year warranty. The annual failure rates of the three are 0.48%, 0.63%, and 1.12%, respectively, and the reliability in the data analysis period is above 97%. Overall, however, Hitachi drives still outperformed Seagate’s offerings.
There are also three hard drives in the 14TB capacity, namely Toshiba’s MG07ACA14TA, Seagate’s ST14000NM001G, and Western Digital’s WUH721414ALE6L4. The corresponding annual failure rates are 0.83%, 1.00%, and 0.33%, respectively, and the reliability is relatively good due to the short use time.
It is worth noting that the reliability of Toshiba’s hard drives will decrease significantly after two years of use. BackBlaze said Western Digital is more popular with consumers than Seagate’s hard drives due to reliability issues, as well as cost.