Hard drive manufacturers publish all sorts of information about the durability of their products, but any estimate pales in comparison to the data held by cloud service companies. Basically, they consume hard drives like cartridges, and the people at Backblaze surpassed one billion drive-hours in the first quarter of the year, giving them very solid failure rates to report.
Buying a hard drive should be a simple decision, but appearances deceive. The truth is that we store a large part of our digital lives on them, and any chance of failure should be set in the very, very distant future. It is likely that the average user gets more hours from a consumer-grade drive, but cloud-focused companies do not have that luxury. For them, drive failures are much more common, and replacements must be ready immediately, since downtime is the mortal enemy of any online business, regardless of size. That brings us to Backblaze, which since April 2013 has accumulated a huge amount of data on the durability of its drives. The report they published in January 2014 was particularly interesting, but they have grown a lot, and during the week they decided to share more details:
The first table focuses on the first quarter of this year, exactly from January 1 to March 31 inclusive. Backblaze explains in a special document how it calculates the annual failure percentage, which can be misleading if we don't look carefully. The example of the Toshiba DT01ACA300 model is compelling: Out of a total of 47 drives, a single failure puts the percentage at 8.63 percent. On the other hand, some models have recorded no failures so far this year, leaving their index at zero (for now). The best relationship between number of failures and number of active units is held by the HGST HMS5C4040BLE640, a four-terabyte drive at 5,400 revolutions. Backblaze started the year with 3,091 of these units, and the failure rate is zero. The problem is that it's not easy to find these days. Demand is high despite its 5,400 RPM, and its price is not so friendly.
When combining all models and all capacities, Backblaze's failure study tells us that the four main manufacturers improved their numbers. This is especially true for Seagate, which blew through 10.68 percent last year, and now moves through 2016 with 3.48 percent, even though the company has more than twice as many drives. Two problems Backblaze faces with Toshiba and Western Digital are price and availability. In Toshiba's case, the final numbers are not good even when buying in large quantities, while every attempt to purchase batches of five or ten thousand WDC drives simply failed. In summary: Hitachi (HGST) comfortably remains at the head in durability, but Seagate improved a lot with the replacement of its unstable 3TB units with superior models.
Editor's note: It is necessary to remember that Backblaze uses consumer-grade drives, and not 'Enterprise' class. At the same time, Backblaze does not recommend using its numbers as a "definitive shopping guide". And as always, make backups.
