Storage examine signifies SSDs fail much less usually than HDDs, and in addition possibly not
Which is the extra dependable storage medium, a strong state drive (SSD) or a tough disk drive (HDD)? To assist reply that query, cloud backup supplier Backblaze offered some attention-grabbing drive failure stats in its newest reliability report, and issues are wanting good for SSDs. Thus far, anyway.
Prior to now, Backblaze has by no means included SSD stats into its reliability reviews. It solely started utilizing SSDs as boot drives just a little over two years in the past, as that’s when it might lastly procure fashions round 200GB in capability for lower than $50, which is what it was paying for 500GB HDDs.
So now two years later, Backblaze is ready to examine failure charges between its SSDs and HDDs as boot drives, from throughout the identical surroundings. Out of the 1,518 SSDs deployed, solely two of them failed final quarter (January 1 by March 31, 2021), for an annualized failure fee of 0.58%.
In the meantime, 44 out of 1,669 HDDs failed throughout the identical time interval, leading to a a lot increased annualized failure fee of 10.56%.
Backblaze additionally offered lifetime HDD and SSD annualized failure charges, from April 20, 2013 to March 3, 2021. Over the previous eight years, Backblaze skilled 559 HDD failures, for a 6.04% annualized failure fee, in comparison with eight SSD failures for a piddly 0.65% failure fee.
Merely put, “SSD drives fail much less usually than HDD drives,” so case closed, proper? Not so quick. Backblaze readily acknowledges “that ignores one necessary issue: drive age.”
“If we deal with the age of every of the cohorts, there are potential cracks in our ‘SSD drives are higher’ supposition,” Backblaze says.
On common, the SSDs included within the newest reliability report are simply 12.7 months outdated, versus the common age of the HDDs deployed as boot drives being 49.6 months. The oldest SSD in Backblaze’s secure is 30 months, whereas the youngest HDD is 24 months. And the oldest HDD is 96 months, or eight years).
So there’s a large discrepancy in drive age, and it’s a information level that issues in the case of evaluating storage reliability and drive failure stats.
“Mainly, the timelines for the age of the SSD and HDD drives don’t overlap very a lot and basically drive failure charges usually enhance as drive inhabitants ages. These two concerns make the conclusion that SSD fail much less usually than HDD drives not as clear minimize because it first appears,” Backblaze says.
There’s one other facet that’s not actually mentioned intimately by Backblaze, that being the restricted write sturdiness of SSDs. That turns into an even bigger issue when utilizing an SSD to carry out frequent backups—NAND flash reminiscence cells put on out after many repeated writes. This does not matter fairly as a lot when shopping for an SSD for a gaming PC (although usually talking, if on the lookout for the finest SSD for gaming, it is best to nonetheless take into account the endurance score in terabytes written, or TBW).
In all probability for that cause, Backblaze doesn’t use SSDs for storing buyer information. Nonetheless, the corporate says labeling them as boot drives “is a misnomer as this cohort can also be used to retailer log recordsdata for system entry, diagnostics, and extra.” They’re commonly studying and writing information, in different phrases, and deleting recordsdata, that are chores along with booting up servers.
So what is the takeaway? Within the early going, it certain appears SSDs fail much less usually than HDDs, no less than in a supercharged boot surroundings. However extra time and stats are wanted for a greater comparability with HDDs. Within the extra fast future, Backblaze says it should plans to look at failure stats from the early years of every storage medium, and can publish these leads to the approaching months.