By Graham K. Rogers

As many users are moving more towards the idea of external storage as an option, partly because of the high cost of solid state drives, it is useful to be able to compare costs of hard disks. Perhaps more important is the reliability. There is no point buying disks if they are going to fail: that increases costs and there is the risk of data loss.

A useful comparison of hard disk failures, by Brian Beach of Backblaze shows a number of interesting comparisons, both in tabel form and with comments. The article is useful because this comes from a backup service that has "41,213 disk drives spinning in our data center" - providing an unlimited backup service. Clearly it is of concern to an operator of such an operation to find the best disks.

Seagate appears to be the best of disks and the worst of disks, with the Seagate 6 TB SATA 3.5 showing a 0% annual failure rate, while the Barracuda 7200.11 and 7200.14 had failure rates of 23.5% and 43.1% respectively. HGST, Toshiba and Western Digital fared better.

Chart from Brian Beach Backblaze

The article defines what Backblaze calls a failure and comments on what appear to be the best drives: 4TB drives fare especially well, while the Seagate Desktop HDD.15 has a good price/failure ratio.

For the full article, which contains far more valuable information and other chart comparisons see, "What is the Best Hard Drive?", Brian Beach Backblaze.

Graham K. Rogers teaches at the Faculty of Engineering, Mahidol University in Thailand where he is also Assistant Dean. He wrote in the Bangkok Post, Database supplement on IT subjects. For the last seven years of Database he wrote a column on Apple and Macs. He is now continuing that in the Bangkok Post supplement, Life.