New data illustrates the impact of time on hard drive failure rates

Solid state drives have usurped hard disk drives (HDDs) when it comes to performance, but whether it’s building a network-attached storage (NAS) or needing high capacity on a budget, many people still rely on spinning platters. However, older drives that have been used frequently may not be as reliable as they used to be. Data released this week by Backblaze shows how hard drive average failure rates (AFR) can increase with age.

Backblaze, a backup and cloud storage company, has been publishing an annual report since 2013 that analyzes the AFR of hard drives in its data center. The 2022 report released on Tuesday looks at 230,921 hard drives across 29 models from HGST, Seagate, Toshiba and WDC ranging in capacity from 4TB to 16TB. All models included at least 60 drives not previously used for testing.

Keep in mind that the reference group only consists of discs that Backblaze had on hand, and they are of varying ages, with some of them being used longer than others. However, Backblaze’s report gives us a unique look at the results of long-term hard drive use.

If you need a reminder of the painful nature of time, Backblaze’s report provides evidence that hard drives’ AFRs increase with age. It’s not surprising news, but Backblaze is providing data to paint a picture of what it looks like.

An analysis of the results by Backblaze found that the graph below “shows that older drives, grouped by size, fail more often.”

Backblaze noted that the increase in AFR as a hard drive ages follows a bathtub curve, where failures tend to be higher at release before dropping, leveling off, and then increasing as the product ages. Backblaze said its hard drive average failure rate was 1.01% in 2021 and 1.37% in 2022.

“The aging of our hard drive fleet seems like the most logical reason for increasing AFR in 2022. We could dig further, but this is probably a moot point at this point,” the Backblaze blog says.

The oldest (mean age 92.5 months) hard drive Backblaze tested was a 6TB Seagate (ST6000DX000). Its AFR was 0.11 percent in 2021 and 0.68 percent in 2022. Backblaze said it was “a very respectable figure at any time, but especially after nearly eight years.”

Seagate, followed by Toshiba, topped the Backblaze chart by grouping AFRs by vendor, but most Seagate drives are much older than the rest of the drives tested.

“In general, Seagate drives are cheaper and their failure rates tend to be higher in our environment,” Backblaze said. “However, their failure rate is generally not high enough to make them less cost-effective over their lifetime. You can make a strong case that many Seagate drives are just as cost effective for us as more expensive drives.”