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Data lifespan on SSDs

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What I want to know is information about data lifespan. I've heard that data can safely reside on traditional HDDs for about 10 years. I figure that eventually, as prices fall and capacities increase, we will see a move to SSD for data storage. Whether it is a file server or backup drives that are stored unused I want to know the lifespan of data on these drives. I'm not sure if it makes a difference whether a drive is being used or is sitting on a shelf in storage. What I'd like to know is the data lifespan from the moment it is written. So, I'd like the following information if anyone knows:

HDD Data lifespan

Drives in use:

Drives in storage:

SSD Data lifespan

Drives in use:

Drives in storage:

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SSDs can be "tuned" via the controller to emphasize different things, so data lifespan on an SSD will vary somewhat along with the controller. Typically from what I've read, data on a drive marketed toward enterprise users will be retained for 3 months after the write cycles of the flash are exhausted and data on consumer-driven SSDs will last for a year after the write cycles are exhausted.

I'm not sure how long data is retained on SSDs while there are write cycles still available - it may be longer or the same amount of time. According to Anandtech, SSDs lose their charge (and their data) after roughly 10 years regardless, so with an SSD tuned for maximum data retention you could keep data intact for 10 years.

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SSDs can be "tuned" via the controller to emphasize different things, so data lifespan on an SSD will vary somewhat along with the controller. Typically from what I've read, data on a drive marketed toward enterprise users will be retained for 3 months after the write cycles of the flash are exhausted and data on consumer-driven SSDs will last for a year after the write cycles are exhausted.

I'm not sure how long data is retained on SSDs while there are write cycles still available - it may be longer or the same amount of time. According to Anandtech, SSDs lose their charge (and their data) after roughly 10 years regardless, so with an SSD tuned for maximum data retention you could keep data intact for 10 years.

Thanks for replying. So, if you want to keep your data long-term you would need to write the data to another drive every ten years (before the drive stopped carrying a charge). This would be the same regardless if the storage drive is HDD or SSD. Is that correct?

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5 years is the effective drive life generally quoted by manufacturers, though I suspect they'd often live longer. Intel had some info about long term data storage on SSDs, I'll see if I can find that. I think their indication though was something like one year if the drive was powered off.

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I can't seem to find the exact session I think I'm remembering, but check this post out, Intel's IDF sessions are the best in terms of info about endurance and what client and enterprise users need to be looking for. Intel and Micron are the only ones I can think of off hand that are regularly reporting their endurance data.

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I can't seem to find the exact session I think I'm remembering, but check this post out, Intel's IDF sessions are the best in terms of info about endurance and what client and enterprise users need to be looking for. Intel and Micron are the only ones I can think of off hand that are regularly reporting their endurance data.

As we move more and more into the digital age we need a cost-effective way to store our data. I don't want to find out ten years down the road that I no longer have my pictures, documents, videos and music. We need to know how often we need to replace our storage drives in order to maintain data integrity. Thank you for the link. I found the information very useful.

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I agree, but right now, if longevity is most important to you, I'd go with a HDD. And even then, depending on your data storage plan, I'd probably have multiple copies.

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Any important data I store on a RAID array with multiple parity, checksums, and regular verify.

I've never seen data actually "age" on a hard drive, and drives with data that haven't been modified for well over 5 years remain readable, though I've not handled enough data that's been unchanged for 5 years to say this is the norm. My experience is that as long as the drive remains alive, data can be stored on it indefinately.

I have no experience with SSDs though, but I guess the data on them will eventually need refreshing. If you're storing static data on them long-term though, that simply means refreshing it in-place rather than copying them off onto another device. As long as you do this once a year, I don't see why it would degrade over time.

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Thanks for replying. So, if you want to keep your data long-term you would need to write the data to another drive every ten years (before the drive stopped carrying a charge). This would be the same regardless if the storage drive is HDD or SSD. Is that correct?

That would be true for SSDs that are tuned for maximum data life, but unless you can afford to have them custom built for you, no SSDs are currently tuned that way. I agree with qasdfdsaq's proposed solution of re-writing the data at least once per year in order to ensure its integrity. You'll still have to change drives in 10 years, but that way the data is likely to stay intact during its time on the SSD.

Edited by Djembe

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NAND flash memory starts its life with a pretty significant data retention rate after one cycle. For MLC memory after it has been cycled for its specified program/erase cycles (whatever that happens to be for that particular MLC memory) it will retain the last thing written to it for about 1 year if you remove power and sit it on a shelf. If you look at eMLC (enterprise MLC) memory, it is essentially the same die as MLC memory, but it is slightly modified by the manufacturer to enable much longer program/erase cycles. What it gives up is retention time once it reaches that higher program/erase time. If the standard MLC is 5,000 cycles, the same die in the eMLC configuration might last 20,000 or 30,000 cycles, but the retention time is only 3 months after you remove power. This is fine for an enterprise environment where you do not archive data on the SSD and park it on a shelf, but would not be good for the consumer that sits the laptop on the shelf without power until the next trip to the country when you find the drive won't boot because it forgot some key data in the boot sector.

When you see a spec for the warranty period of the drive, that is related to how long the manufacturer says the drive will operate without a manufacturing fault. Some manufacturers specify the maximum number of bytes that can be written to the drive, but that does not tell the user when they hit that point in the drive's life. Under light use you may not hit that number of bytes written ever and in heavy use you may hit that before the warranty is up. Check the manufacturer specs closely to see if they cover the warranty if you exceed the bytes written in less than the warranty period.

Magnetic media (an HDD) certainly has a period where it will remember the data written to it, but it is much longer than an SSD.

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