Most Reliable HDDs From Toshiba Among 110,640 Units From 3 Manufacturers

This article was written on August 6, 2019 by Andy Klein, director of product marketing, Backblaze, Inc.

Backblaze HDD Stats 2Q19

As of June 30, 2019, Backblaze had 110,640 spinning HDDs in its ever-expanding cloud storage ecosystem. Of that number, there were 1,980 boot drives and 108,660 data drives.

This review looks at the 2Q19 and lifetime HDD failure rates of the data drive models currently in operation in our data centers.

We’ll also say goodbye to a couple of drive models that have been around for several years, take a look at how our 14B Toshiba drives are doing (spoiler alert: great), and along the way we’ll provide a handful of insights and observations from inside our storage cloud.

As always, we’ll publish the data we use in these reports on our HDD Test Data web page.

HDD Failure Stats for 2Q19
At the end of 2Q19, Backblaze was using 108,660 HDDs to store data. For our evaluation its removes from consideration those drives that were used for testing purposes and those drive models for which we did not have at least 60 drives (see why below). This leaves us with 108,461 HDDs. The table below covers what happened in 2Q19.

Notes and Observations
If a drive model has a failure rate of 0%, it means there were no drive failures of that model during 2Q19 – lifetime failure rates are later in this report. The two drives listed with zero failures in Q2 were the 4TB and 14TB Toshiba models. The 4TB drive doesn’t have a large enough number of drives or drive days to be statistically reliable, but only one drive of that model has failed in the last three years. We’ll dig into the 14TB Toshiba drive stats a little later in the report.

There were 199 drives (108,660 minus 108,461) that were not included in the list above because they were used as testing drives or we did not have at least 60 of a given drive model. We now use 60 drives of the same model as the minimum number when we report quarterly, yearly, and lifetime drive statistics as there are 60 drives in all newly deployed Storage Pods – older Storage Pod models had a minimum of 45.

2,000 Backblaze Storage Pods? Almost …
We currently have 1,980 Storage Pods in operation. All are version 5 or version 6 as we recently gave away nearly all of the older Storage Pods to folks who stopped by our Sacramento, CA storage facility. Nearly all, as we have a couple in our Storage Pod museum. There are currently 544 version 5 pods each containing 45 data drives, and there are 1,436 version 6 pods each containing 60 data drives. The next time we add a Backblaze Vault, which consists of 20 Storage Pods, we will have 2,000 Backblaze Storage Pods in operation.

Goodbye Western Digital
In 2Q19, the last of the Western Digital 6TB drives were retired from service. The average age of the drives was 50 months. These were the last of our Western Digital branded data drives. When Backblaze was first starting out, the first data drives we deployed en masse were Western Digital Green 1TB drives. So, it is with a bit of sadness to see our Western Digital data drive count go to zero. We hope to see them again in the future.

Hello Western Digital
While the Western Digital brand is gone, the HGST brand (owned by Western Digital) is going strong as we still have plenty of the HGST branded drives, about 20% of our farm, ranging in size from 4TB to 12TB. In fact, we added over 4,700 HGST 12TB drives in this quarter.

This just in; rumor has it there are 20 14TB Western Digital Ultrastar drives getting readied for deployment and testing in one of our data centers. It appears Western Digital has returned: stay tuned.

Goodbye 5TB Drives
Back in 1Q15, we deployed 45 Toshiba 5TB drives. They were the only 5TB drives we deployed as the manufacturers quickly moved on to larger capacity drives, and so did we. Yet, during their four plus years of deployment only two failed, with no failures since 2Q16 – 3 years ago. This made it hard to say goodbye, but buying, stocking, and keeping track of a couple of 5TB spare drives was not optimal, especially since these spares could not be used anywhere else. So yes, the Toshiba 5TB drives were the odd ducks on our farm, but they were so good they got to stay for over 4 years.

Hello Again Toshiba 14TB Toshiba Drives
We’ve mentioned the Toshiba 14TB drives in previous reports, now we can dig in a little deeper given that they have been deployed almost 9 months and we have some experience working with them. These drives got off to a bit of a rocky start, with 6 failures in the first three months of being deployed. Since then, there has been only one additional failure, with no failures reported in 2Q19. The result is that the lifetime annualized failure rate for the Toshiba 14TB drives has decreased to a very respectable 0.78% as shown in the lifetime table in the following section.

Lifetime HDD Stats
The table below shows the lifetime failure rates for the HDD models we had in service as of June 30, 2019. This is over the period beginning in April 2013 and ending June 30, 2019.

The HDD Stats Data
The complete data set used to create the information used in this review is available on our HDD Test Data web page.

If you just want the tables we used to create the charts in this blog post you can download the ZIP file containing the MS Excel spreadsheet.