Backblaze releases Q2 version of 2021 HDD failure rate report for a total of nearly 180,000 HDDs, and also compares HDD and SSD failure rates

Backblaze , a cloud storage service provider, operates four data centers across two continents as of the end of June 2021 and owns 178,166 data drives and 3298 boot drives. doing. Backblaze has released a failure rate report for HDDs and SSDs in the second quarter of 2021 (April 1, 2021 to June 30, 2021).

Hard Drive Reliability: A Look at HDD and SDD Failure Rates

From the 178,166 HDDs that Backblaze owned as of the end of June 2021, a total of 177,935 HDDs, excluding models for testing and less than 60 units, had a failure rate in the second quarter of 2021. The table showing is as follows. The total number of HDDs is 177,935, the total number of operating days for three months is 15,884,445 days, the number of failed HDDs is 439, and the total annual average failure rate (AFR) is 1.01%. The AFR in the first quarter of 2021 was 0.81%, and it is said that the AFR started to rise for the first time in about a year.

In the second quarter of 2021, Seagate 's 6TB 'ST6000DX000', HGST 's 12TB 'HUH721212ALE600', and WDC 's 16TB '16TB WUH721816ALE6L0' achieved zero failures. Of these, Seagate's 'ST6000DX000' is a fairly old model with an average operating life of over 74 months (6 years and 2 months), but it is said that only one unit failed in 2020. On the other hand, WDC's '16TB WUH721816ALE6L0' is only three months old, but Backblaze says it's great that 624 units got off to a good start.

On the other hand, Toshiba's 4TB 'MD04ABA400V' which recorded 4.07% and Seagate's 14TB 'ST14000NM0138' which 5.55% failed had AFR exceeding 4%. Toshiba's 'MD04ABA400V' has only 98 units in operation, so even if one unit fails, the AFR will exceed 4%. 'ST14000NM0138', which failed 23 out of 1653 units, was introduced to Dell's storage server in the western part of the United States from 2021, and Backblaze worked with Dell to identify the root cause of the high failure rate. It is said that it is.

In addition, since AFR is greatly affected by the number of models and the number of working days, Backblaze has AFR for models with 'Drive Days, which is the cumulative number of models x operating days, is 250,000 days or more'. It is said that the legitimacy of can be guaranteed. Looking at the models with more than 250,000 driving days, the lowest AFR was 0.14% recorded by HGST's 12TB 'HUH721212ALE604', and the highest was 2.06% recorded by Seagate's 12TB 'ST12000NM0007'. It has become.

Backblaze also uses both HDDs and SSDs for its boot drive, and publishes a comparison of their failure rates. The HDD failure rate from April 2013 to December 2020 is as follows. Of the total 9670 units, 551 units failed, and the total AFR was 6.26%.

On the other hand, the SSD failure rate from April 2013 to December 2020 is as follows, and 7 out of 1614 units have failed, and the total AFR is 0.79%.

At first glance, SSDs seem to be overwhelmingly less likely to fail than HDDs, but Backblaze points out that HDDs and SSDs have different life cycles. The average number of operating months for HDDs was '49.63 months', while the average number of operating months for SSDs was '12.66 months'.

Therefore, Backblaze calculated the HDD failure rate in the span from April 2013 to December 2015, when the average number of operating months of HDD was close to '12.66 months'. The table below shows that 11 of the total 1160 units failed, with AFR of 1.54%.

This is a table comparing the HDD failure rate and SSD failure rate when the life cycle is combined. Although the opening is smaller than when there was no adjustment, it was confirmed that SSDs tend to be less likely to break down.

Graphing the failure rate transition from the introduction of HDD and SSD, the transition from 2014 to 2016 for HDD and the transition from 2018 to 2020 for SDD are similar. Backblaze said in a future report whether SSD failure rates will rise in the same way as HDDs or will follow a different transition from HDDs.

in Hardware, Posted by log1h_ik