The life span of Hard Drives
Under Normal Use
Any hard drive in active use is essentially a ticking bomb. Let’s be honest: It’s not a matter of if a hard drive fails, it’s a matter of when, and how lucky you’ll get postponing that as long as possible. If you’re really lucky, it will be after you’ve upgraded to a new one. If you’re unlucky, it will be in a matter of months or years, and we can only hope you’ve made sure to back up your computer before it happens.
As for the average life of the hard drive in your computer, well, that depends mostly on whether it’s an HDD or an SSD. Here’s the basic breakdown and some average life expectancy:
- Hard Drives: Traditional hard drives, which you’ll usually find in desktop computers (and some cheaper laptops) will often fail sooner because they use moving parts. The average life of a hard drive depends on a lot of things, like the brand, type, size and interface method, but you’re looking at about four years on average. Online backup service Backblaze studied the drives in their infrastructure and found about 80 per cent of them survived for four years. Of course, that also means 20 per cent didn’t and failed sooner, most of those in the third year of use. Similarly, the brand of drive you use makes a difference. Seagate, for example, failed much more frequently than Western Digital or Hitachi drives in Backblaze’s tests. You can check out the raw data on all 41,000 drives for more. In short, keep your data backed up, watch for SMART alerts, and keep an eye on your hard drive’s warranty. Most are about two to three years, and while your drive may last much longer than that, be ready for failures after that point.
- Solid State Drives: Solid state drives, which have become extremely popular in laptops and desktops for their faster speeds, are different. You may hear people say that you have to be careful with SSDs because they have a limited number of reads and writes. In reality, consumer SSDs actually last a really, really long time under normal use. TechReport’s famous SSD endurance test showed us that a lot of those fears are over-blown, and even consumer SSDs managed to survive writing and reading well over 700TB of data. These drives usually come with a three to five year warranty, and manufacturers assume you’ll write 20GB-40GB per day in data. That means to get to that 700TB, you’d have to do 40GB every day for 17,500 days, or just shy of 50 years. That doesn’t mean you should mistreat your drive, and it doesn’t mean SSDs won’t fail due to other issues, but if you’re worrying your SSD will die because you used it too much, don’t.
Of course, all of this is average data. Your experiences may differ, and you may wind up with a great drive that lasts forever, or another one that fails a few days out of the box. That’s why it’s important to keep your systems backed up. Beyond that though, stick to trusted brands with solid warranties that don’t make it a nightmare to RMA a drive that dies before its prime.
How long does an SSD last?
If you deal with the expected life span of an SSD, you first have to have a look at the variable storage types of SSD drives. Three SSD storages are available: Single Level Cell (SLC), Multi Level Cell (MLC) and Triple Level Cell (TLC). These names already adumbrate the difference. The storage type MLC saves two bits per storage cell, the TLC type three bits per cell and the SLC type only one bit. SLC flash storages haven’t become accepted yet because of their horrendous prices.
For the storage types and their life span applies the following: The more data per cell is saved, the higher the wear level is. That means, at first the life span of storage types possibly can be linked to the write cycles. Storage cells of type MLC last about 3,000 write cycles. In the first moment, that necessarily doesn’t sound much. However, in comparison to conventional HDDs, the mechanics of SSD don’t degrade when only reading data. This means, by only reading data, an SSD will not wear out, which brings us to the conclusion that it depends on the write and delete processes.
With “Wear Leveling” SSDs have made a big step towards more robustness. SSDs of the new generations apportion data on the whole storage. By this, all storage cells are treated with care as good as possible. Meanwhile, some SSDs have a so-called SLC mode. We are already familiar with the term from the storage types as explained above. Per storage cell, only one bit is written on an SLC SSD. When an MLC or TLC drive runs in SLC mode, it virtually emulates an SLC storage and writes only one bit per cell at the beginning. Once the storage space isn’t sufficient anymore, the drive switches to working in the normal storage procedure mode.
Let’s undergo an endurance test with modern SSDs, which means constantly writing on these flash storages at highest speed by using special tools. By now, SSDs achieve outstanding results in such tests. Only after years there are storage cell drop outs. However, even for these inoperable cells flash storages have a successful solution. Current SSDs have reserve capacities. These storage spaces aren’t available to the user, but are used to repair damaged cells, so to speak. The defect cells are replaced with brand-new reserve cells; this procedure is called “Bad-Block-Management”. Thus, SSD storage cells in normal operation last a lifetime.
Can I calculate the life span of an SSD drive?
The more storage cells an SSD owns, the longer it will work. By having a huge storage capacity the storage cells can be treated with care for much longer because they aren’t rewritten that often. The life span of a modern SSD can be calculated with the help of a formula:
Let’s take the Samsung 850 PRO as an example. The 850 PRO is an MLC SSD with 3,000 write cycles. The capacity of the drive differs depending on the model, ranging from 512GB to 2TB. The SSD factor specifies the rate of the real amount of data to the actual data written. For the calculation, one chooses a high value of 5. In addition, the amount of data that is written on the drive per year is estimated. If an estimation is difficult, then we recommend to choose a value between 1,500 and 2,000GB.
The life span of a Samsung 850 PRO with 1TB then results in:
This SSD will probably last incredible 343 years. This isn’t a guarantee, but a good forecast. The warranty for the named SSD is ten years. Also, TLC drives don’t have to hide. The 1TB model of the Samsung 850 EVO series, which is equipped with the low-priced TLC storage type, can expect a life span of 114 years.
If your SSD is already in usage for a while, then you can calculate the anticipated remaining life time with the help of special tools. The tool SSDlife calculates the working time so far, the amount of data already written and gives a rating regarding the life span.
If You Aren’t Using Your Hard Drive at All
The other side of the coin involves “cold storage”. If you write data to a drive and then, let’s say, drop it in a safe deposit box or a time capsule, how long would the data on it survive before it degrades? If you’re talking about true cold storage — as in you don’t want to access it for years, perhaps decades at a time, the numbers change a bit.
Again, things are different depending on whether you’re talking about SSDs or traditional HDDs. Here’s what you need to know:
- Hard Drives: If you’re planning to drop some data on a hard drive and toss it into a storage unit or a safe deposit box, you probably don’t need to worry about the data deteriorating as long as your drive is in a climate controlled environment, the only issue to worry about is the oil around the ball bearings drying out. In short, spin them up every few years — which you should do anyway to make additional backups and switch storage methods (which we’ll get to a little later.) If your environment isn’t climate controlled, well — just make sure it’s climate controlled. A time capsule in the ground with a hard drive in it likely won’t survive to be dug up and read.
- Solid State Drives: SSDs for archival purposes is a difficult thing to pin down. SSDs are still relatively new technology, especially compared to magnetic media (which most businesses still use for archival backups) so there aren’t many serious studies as to their long-term survivability in cold storage. We have an idea that, under power, SSDs can last a good long time, but even SSD technology is evolving (future consumer SSDs will likely be PCI, just for speed purposes, the way enterprise SSDs have been for a while) and everything could change again in a matter of years. Theoretically though, assuming a climate controlled environment the only thing you’d have to worry about is the slow degradation of data in the drive’s NAND cells, but that’s a process that takes decades, possibly longer.
Long story short, if you keep a hard drive offline and in a box — as long as it’s someplace well maintained, you’l
l have other problems to worry about long before the eventual degradation of the data on the drive. Conceivably, you could keep either for decades, probably longer, and then fire them up and they will work as good as they did the last time they were powered down, and the data would be right there for you to read.
The More Important Factor: Interface Technology
All this talk about the mechanical or physical life of storage is great, but it misses the biggest, most important point: The pace of technology, and how quickly your drive’s connection interface or platform will be obsolete. After all, it wasn’t too long ago that the hard drive interface standard was IDE, then SATA, then SATA II and III. For external media, long before we had USB 3 and Thunderbolt, we made do with Parallel Port and Serial connections. While the drives buried inside those old Parallel Port or IDE-based storage devices probably still function, and still have their precious data on them, you need to find equally old technology (or working converters and adapters) to retrieve it.
This is a bigger issue, one that data archivists struggle with, and a more pressing matter for anyone thinking about saving data for posterity — or trying to hand down electronic information to future generations. If you think you can slap some precious photos onto a 1TB USB drive, put it in a safe deposit box at the bank, and will it to your children with instructions to open it when you pass away, it’s a gamble that (depending on how old you are, of course) there will be any USB devices left by the time they get around to seeing what’s on it. Just think: If someone handed you a ZIP disk today and told you there was something important on it for you, how would you go about getting at that data? What about a 5.25-inch floppy? Your best bet is to, instead of setting and forgetting it, to diversify your storage methods, update data and drive formats every few years, and keep more than one type of backup whenever possible.