Enterprise hard disks are faster and use more power, but are they more reliable?

Backblaze, the low-cost cloud backup and storage provider, has published its drive reliability numbers for the first quarter of 2017.

Over most of its life, Backblaze's focus on high density and low cost has seen the company use consumer-oriented hard drive models for its storage service, applying replication and Reed-Solomon encoding to protect against individual disks failing. This has given useful insight into the longevity of a range of consumer hard disk models, albeit under conditions that are probably a bit more hostile than most of us have to contend with, thanks to a mix of vibration and thermal environment.

But the company recently scored a deal on 8TB Seagate enterprise disks, buying 2,459 of them. The disks have been deployed over the first quarter. It's too soon to make any inferences about reliability, as even the oldest disks have only been in production for a couple of months, but the company has noticed a few differences immediately.

The enterprise disks offer a tangible improvement in transfer rates, increasing the ingest rate for each rack of disks from about 100TB per day to 140TB per day. For the company's usage model, this isn't tremendously important, as its workload is spread over many racks of disks; the higher speed just means that the enterprise disks show themselves as being ready for new data more rapidly.

The enterprise disks also use more power: 9W idle and 10W operational, compared to 7.2W idle and 9W operational for comparable consumer disks. If you have one or two spindles, that's no big deal, but each Backblaze rack has 20 "storage pods" with 60 disks each. An extra 2.2kW for an idle rack is nothing to sniff at.

The bulk of the company's storage remains on consumer disks, and there, as ever, the HGST models are putting in a strong performance. In the last quarter of 2016, three specific models of disk suffered no failures, and one of those models, the 8TB HGST, showed no failures for a second quarter running. The company doesn't have very many of these disks, only 45, but it's nonetheless a notable achievement.

Other HGST models are also continuing to show impressive longevity, with three 4TB models and one 3TB model both boasting a sub-1 percent annualized failure rate.

Backblaze's newest workhorse drive, an 8TB consumer-oriented Seagate, is also putting in a compelling performance. While the older 4TB disks had a failure rate of about 3 percent, the latest 8TB drives appear to have roughly halved that, at 1.6 percent.