4 ms·

Unpowered SSD endurance investigation finds data loss and performance issues

123 points by progval 1y ago

csdvrx 1y ago
For long term storage, prefer hard drives (careful about CMR vs SMR) If you have specific random IO high performance needs, you can either - get a SLC drive like https://news.solidigm.com/en-WW/230095-introducing-the-solidigm-d7-p5810-an-ultra-fast-slc-ssd-for-write-intensive-workloads https://news.solidigm.com/en-WW/230095-introducing-the-solid... - make one yourself by hacking the firmware: https://news.ycombinator.com/item?id=40405578 https://news.ycombinator.com/item?id=40405578 Be careful when you use something "exotic", and do not trust drives that are too recent to be fully tested: I learned my lesson for M2 2230 drives https://www.reddit.com/r/zfs/comments/17pztue/warning_you_may_want_to_avoid_some_western/ https://www.reddit.com/r/zfs/comments/17pztue/warning_you_ma... which seems validated by the large numbers of similar experiences like https://github.com/openzfs/zfs/discussions/14793 https://github.com/openzfs/zfs/discussions/14793
- dragontamer 1y ago
  If you care about long term storage, make a NAS and run ZFS scrub (or equivalent) every 6 months. That will check for errors and fix them as they come up. All error correction has a limit. If too many errors build up, it becomes unrecoverable errors. But as long as you reread and fix them within the error correction region, it's fine.
  - csdvrx 1y ago
    > run ZFS scrub (or equivalent) every 6 months zfs in mirror mode offers redundancy at the block level but scrub requires plugging the device > All error correction has a limit. If too many errors build up, it becomes unrecoverable errors There are software solutions. You can specify the redundancy you want. For long term storage, if using a single media that you can't plug and scrub, I recommend par2 (https://en.wikipedia.org/wiki/Parchive?useskin=vector https://en.wikipedia.org/wiki/Parchive?useskin=vector) over NTFS: there are many NTFS file recovery tools, and it shouldn't be too hard to roll your own solution to use the redundancy when a given sector can't be read
  - WalterGR 1y ago
    What hardware, though? I want to build a NAS / attached storage array but after accidentally purchasing an SMR drive[0] I’m a little hesitant to even confront the project. A few tens of TBs. Local, not cloud. [0] Maybe 7 years ago. I don’t know if anything has changed since, e.g. honest, up-front labeling. [0*] For those unfamiliar, SMR is Shingled Magnetic Recording. https://en.m.wikipedia.org/wiki/Shingled_magnetic_recording https://en.m.wikipedia.org/wiki/Shingled_magnetic_recording
    - 3np 1y ago
      Toshi Nx00/MG/MN are good picks. The company never failed us and I don't believe they've had the same kinds of controversies as the US competition. Please don't tell everyone so we can still keep buying them? ;)
    - wmf 1y ago
      Nothing can really save you from accidentally buying the wrong model other than research. For tens of TBs you can use either 4-8 >20TB HDDs or 6-12 8TB SSDs (e.g. Asustor). The difference really comes down to how much you're willing to pay.
    - matheusmoreira 1y ago
      > What hardware, though? Good question. There seems to be no way to tell whether or not we're gonna get junk when we buy hard drives. Manufacturers got caught putting SMR into NAS drives. Even if you deeply research things before buying, everything could change tomorrow. Why is this so hard? Why can't we have a CMR drive that just works? That we can expect to last for 10 years? That properly reports I/O errors to the OS?
    - code_biologist 1y ago
      The Backblaze Drive Stats are always a good place to start: https://www.backblaze.com/blog/backblaze-drive-stats-for-2024/ https://www.backblaze.com/blog/backblaze-drive-stats-for-202... There might be SMR drives in there, but I suspect not.
    - dragontamer 1y ago
      SMR will store your data, just slowly. It was a mistake for the Hard Drive business community to push them so hard IMO. But these days the 20TB+ drives are all HAMR or other heat/energy assisted tech. If you are buying 8TB or so, just make sure to avoid SMR but otherwise you're fine. Even then, SMR stores data fine, it's just really really slow.
  - ErneX 1y ago
    I use TrueNAS and it does a weekly scrub IIRC.
- AshamedCaptain 1y ago
  > (careful about CMR vs SMR) Given the context of long term storage... why?
  - 0cf8612b2e1e 1y ago
    After I was bamboozled with a SMR drive, always great to just make the callout to those who might be unaware. What a piece of garbage to let vendors upsell higher numbers. (Yes, I know some applications can be agnostic to SMR, but it should never be used in a general purpose drive).
  - whoopdedo 1y ago
    Untested hypothesis, but I would expect the wider spacing between tracks in CMR makes it more resilient against random bit flips. I'm not aware of any experiments to prove this and it may be worth doing. If the HD manufacture can convince us that SMR is just as reliable for archival storage it would help them sell those drives since right now lots of people are avoiding SMR due to poor performance and the infamy of the bait-and-switch that happened a few years back.
- sitkack 1y ago
  Tape is extremely cheap now. I booted up a couple laptops that have been sitting unpowered for over 7 years and the sata SSD in one of them has missing sectors. It had zero issues when shutdown.
  - seszett 1y ago
    Is tape actually cheap? Tape drives seem quite expensive to me, unless I don't have the right references.
    - wtallis 1y ago
      Tapes are cheap, tape drives are expensive. Using tape for backups only starts making economic sense when you have enough data to fill dozens or hundreds of tapes. For smaller data sets, hard drives are cheaper.
      - AStonesThrow 1y ago
        HDDs are a pragmatic choice for “backup” or offline storage. You’ll still need to power them up, just for testing, and also so the “grease” liquefies and they don’t stick. Up through 2019 or so, I was relying on BD-XL discs, sized at 100GB each. The drives that created them could also write out M-DISC archival media, which was fearsomely expensive as a home user, but could make sense to a small business. 100GB, spread over one or more discs, was plenty of capacity to save the critical data, if I were judiciously excluding disposable stuff, such as ripped CD audio.
      - sitkack 1y ago
        Used LTO5+ drives are incredibly cheap, you can get a whole tape library with two drives and many tape slots for under 1k. Tapes are also way more reliable than hard drives.
    - dogma1138 1y ago
      If you don’t have a massive amount of data to backup, used LTO5/6 drives are quite cheap, software and drivers is another issue however with a lot of enterprise kit. The problem ofc is that with a tape you need to also have a backup tape drive on hand. Overall if you get a good deal you can have a reliable backup setup for less than $1000 with 2 drives and a bunch of tape. But this is only good if you have single digit of TBs or low double digit of TBs to backup since it’s slow and with a single tape drive you’ll have to swap tapes manually. LTO5 is 1.5TB and LTO6 is 2.5TB (more with compression) it should be enough for most people.
- vlovich123 1y ago
  > - make one yourself by hacking the firmware: https://news.ycombinator.com/item?id=40405578 https://news.ycombinator.com/item?id=40405578 Be careful when you use something "exotic", and do not trust drives that are too recent to be fully tested Do you realize the irony of cautioning about buying off the shelf hardware but recommending hacking firmware yourself?
  - userbinator 1y ago
    That "firmware hack" is just enabling an option that manufacturers have always had (effectively 100% "SLC cache") but almost always never use for reasons likely to do with planned obsolescence.
    - vlovich123 1y ago
      Converting a QLC chip into an SLC is not planned obsolescence. It’s a legitimate tradeoff after analyzing the marketplace that existing MTBF write lifetimes are within acceptable consumer limits and consumers would rather have more storage. Edit: and to preempt the “but make it an option”. That requires support software they may not want to build and support requests from users complaining that toggling SLC mode lost all the data or toggling QLC mode back on did similarly. It’s a valid business decision to not support that kind of product feature.
      - Dylan16807 1y ago
        And for the vast majority of use cases, even if QLC wears out TLC would be fine indefinitely. Limiting it to SLC capacity would be ridiculous.
      - userbinator 1y ago
        I have USB drives with good old SLC flash, whose data is still intact after several decades (rated for retention of 10 years at 55C after 100K cycles - and they have not been cycled anywhere near that much.) and consumers would rather have more storage No one from the manufacturers tells them that the "more storage" - multiplicatively more - lasts exponentially less. For the same price, would you rather have a 1TB drive that will retain data for 10 years after having written 100PB, or a 4TB one that will only hold that data for 3 months after having written 2PB? That requires support software they may not want to build The software is already there if you know where to look. and support requests from users complaining that toggling SLC mode lost all the data or toggling QLC mode back on did similarly Do they also get support requests from users complaining that they lost all data after reformatting the drive? It’s a valid business decision to not support that kind of product feature. The only "valid business decision" is to make things that don't last as long, so recurring revenue is guaranteed. Finally, the "smoking gun" of planned obsolescence: SLC flash requires nowhere near as much ECC and thus controller/firmware complexity as MLC/TLC/QLC. It is also naturally faster. The NRE costs of controllers supporting SLC flash is a fraction of those for >1 bit per cell flash. QLC in particular, according to one datasheet I could find, requires ECC that can handle a bit error rate of 1E-2. One in a hundred bits read will be incorrect in normal operation of a QLC storage device. That's how idiotic it is --- they're operating at the very limits of error correction, just so they can have a measly 4x capacity increase over SLC which is nearly perfect and needs very minimal ECC. All this energy and resource usage dedicated to making things more complex and shorter-lasting can't be considered anything other than planned obsolescence. Contrast this with SmartMedia, the original NAND flash memory card format, rated for 100K-1M cycles, using ECC that only needs to correct at most 1 bit in 2048, and with such high endurance that it doesn't even need wear leveling. Also consider that SLC drives should cost a little less than 4x the price of QLC ones of the same capacity, given the lower costs of developing controllers and firmware, and the same price of NAND die, yet those rare SLC drives which are sold cost much more --- they're trying to price them out of reach of most people, given how much better they actually are.
rkagerer 1y ago
I would never buy a no-name SSD. Did it once long ago and got bit, wrote a program to sequentially write a pseudorandom sequence across the whole volume then read back and verify, and proved all 8 Pacer SSD's I had suffered corruption.
- WalterGR 1y ago
  That’s also fairly common for cheap ‘thumb drives’, as I understand it. I’ve been bitten by that before. (Edit: Allegedly if you use low-numbered storage blocks you’ll be okay, but the advertised capacity (both packaging and what it reports to OS) is a straight-up lie.)
  - WalterGR 1y ago
    (Edit: Retail packaging, I mean. Too late to edit my comment.)
gnabgib 1y ago
Discussion on the original source: (20 points, 3 days ago, 5 comments) https://news.ycombinator.com/item?id=43702193 https://news.ycombinator.com/item?id=43702193 Related: SSD as Long Term Storage Testing (132 points, 2023, 101 comments) https://news.ycombinator.com/item?id=35382252 https://news.ycombinator.com/item?id=35382252
bityard 1y ago
I didn't think it was controversial that SSDs are terrible at long term storage?
- wmf 1y ago
  I wouldn't say it's controversial but I suspect most people don't know about it. There's been a lot of discussion about SSD write endurance but almost none about retention.
- creatonez 1y ago
  Right, but the news is that someone finally actually tested the unplugged-is-worse theory in a long term real world test. So much of the existing data about SSD endurance has been exclusively SSDs in datacenters plugged in 24/7, so it's nice to see some data showing what the difference actually looks like.
jeffbee 1y ago
Endurance is proportional to programming temperature. In the video, when all four SSDs are installed at once, the composite device temperature ranges over 12º. This should be expected to influence the outcomes.
ein0p 1y ago
This is a known issue. You have to power up your SSDs (and flash cards, which are based on even more flimsy/cost optimized version of the same tech) every now and then for them to keep data. SSDs are not suitable for long term cold storage or archiving. Corollary: don't lose that recovery passphrase you've printed out for your hardware crypto key, the flash memory in it is also not eternal.
- RicoElectrico 1y ago
  Please explain to me how is that supposed to work. For all I know the floating gate is, well, isolated and only writes (which SSDs don't like if they're repeated on the same spot) touch it through mechanisms not unlike MOSFET aging i.e. carrier injection. Reading on the other hand depends on the charge in floating gate altering Vt of the transistor below, this action not being able to drain any charge from the floating gate.
  - wmf 1y ago
    According to a local expert (ahem), leakage can occur through mechanisms like Fowler-Nordheim tunneling or Poole-Frenkel emission, often facilitated by defects in the oxide layers.
  - ein0p 1y ago
    If you at least read the data from the drive from time to time, the controller will "refresh" the charge by effectively re-writing data that can't be read without errors. Controllers will also tolerate and correct _some_ bit flips on the fly, topping up cells, or re-mapping bad pages. Think of it as ZFS scrub, basically, except you never see most of the errors.
- jsheard 1y ago
  A not-so-fun fact is that this even applies to modern read-only media, most notably Nintendo game carts. Back in the day they used mask ROMs which ought to last more or less forever, but with the DS they started using cheaper NOR or NAND flash for larger games, and then for all games with the 3DS onwards. Those carts will bit-rot eventually if left unpowered for a long time.
jauntywundrkind 1y ago
Note: the worn drives were very worn. 128GB drive with 280TB written is ~2400 cycles. >5x it's 480x rating! Even though it's a cheap drive, it's rated endurance wasn't really that low. 600 cycles (1200TBW/2TB) is pretty common for consumer SSD: that's higher than 480x but not vastly higher. Glad folks are chiming in with the temperature sensitivity notes. I have parts coming in for a much bigger home-cloud system, and was planning on putting it in the attic. But it's often >110°F in the summer up there! I don't know how much of a difference that would make, given that the system will be on 24/7; some folks seem to say having it powered on should be enough, others note that usually it's during read that cells are refreshed. Doing an annual dd if=/nvme0n1 of=/dev/zero bs=$((1024*1024)) hadn't been the plan, but maybe it needs to be!
- ilikepi 1y ago
  Ok I gotta ask...why of=/dev/zero and not of=/dev/null ?
  - jauntywundrkind 1y ago
    That's probably much better, oops!
    - gruez 1y ago
      You don't even need dd since you're reading the whole file end to end. Something like cat /dev/nvme0n1 > /dev/null would suffice.
- ahofmann 1y ago
  Just my 2 cents: I've installed quite a few servers and racks of hardware in very unsuitable spaces. LTO drives in dusty rooms, important disks in hot and cold (summer and winter), dusty and vibrating rooms and so on. I was very worried about them dying way sooner than people would expect. The only thing that died after two years was the LTO drives. Everything else is still running. So I wouldn't worry much about your hot attic. 43° Celsius outside means constantly over 50° inside the server, which sounds horrible but in the last 15 years of my experience nothing died because the room was too hot, or cold, or humid, or shaky. I've installed dust Filters in front of all air intakes, though. My reasoning is, that dust kills way faster than temperature.
stego-tech 1y ago
I mean, this reads as I expected it to: SSDs as cold storage are a risky gamble, and the longer the drive sits unpowered (and the more use it sees over its life), the less reliable it becomes. Man, I’d (figuratively) kill for a startup to build a prosumer-friendly LTO drive. I don’t have anywhere near the hardware expertise myself, but I’d gladly plunk down the dosh for a drive if they weren’t thousands of dollars. Prosumers and enthusiasts deserve shelf-stable backup solutions at affordable rates.
- 0manrho 1y ago
  I agree with the general sentiment, but just a headsup for those who might be unaware... > thousands of dollars I know this varies a lot based on location, but if you're stateside, you can get perfectly functional used LTO6 drives for $200-$500 that support 6TB RW cartridges that you can still buy new for quite cheap (20pk of 6TB RW LTO6 carts[0] for $60), much cheaper than any other storage medium I'm aware of and still reasonably dense and capacious still by modern standards. Sure it's 3-4 generations behind the latest LTO's, and you might need to get yourself a SAS HBA/AIC to plug it in to a consumer system (those are quite cheap as well, don't need to get a full RAID controller), but all in that's still quite an affordable and approachable cold storage solution for prosumers. Is there a reason this wouldn't work for you? Granted, the autoloader/enclosed library units are still expensive as all hell, even the hold ones, and I'd recommend sticking to quantum over IBM/HPE for the drives given how restrictive the later can be over firmware/software, but just wanted to put it out there that you don't necessarily need to spend 4 figures to get a perfectly functional tape solution with many many TB's worth of storage. 0: https://buy.hpe.com/us/en/storage/storage-media/tape-media/lto-ultrium-cartridges/hpe-lto%E2%80%916-ultrium-6-25tb-rw-custom-labeled-20-data-cartridges-library-pack-without-cases/p/c7976ac https://buy.hpe.com/us/en/storage/storage-media/tape-media/l...
  - throwaway81523 1y ago
    LTO6 capacity is 2.5TB. 6TB is "compressed" which these days is near worthless because data collections that size are likely to already compressed (example: video). If the idea is to back up a hard drive, it's not nice to require big piles of tape to do it. Right now even the current LTO generation (LTO9, 18TB native capacity) can't back up the current highest capacity hard drives (28TB or more, not sure). In fact HDD is currently cheaper per TB (20GB drive at $229 at Newegg) than LTO6 tape ($30 for 2.5TB) even if the tape drive is free. LTO would be interesting for regular users if the current generation drive cost $1000 or less new with warranty rather than as crap from ebay. It's too much of an enterprise thing now. Also I wonder what is up with LTO tape density. IBM 3592 drives currently have capacity up to 50TB per tape in a cartridge the same size as an LTO cartridge, so they are a couple generations ahead of LTO. Of course that stuff is even more ridiculously expensive.
0manrho 1y ago
Not surprsing. Flash is for hot/warm storage, not for cold storage, but using literal bottom of the bargin-bin barrel no-name drives that are already highly worn really doesn't tell us anything. Even if these were new or in powered on systems for their whole life, I wouldn't have high confidence in their data retention, reliability or performance quite frankly. Granted, there is something to be said about using budget/used drives en masse and brute forcing your way to reliability/performance/capacity on a budget through shear scale, but that requires some finesse and understanding of storage array concepts, best-practices, systems and software. By no means beyond the skills of an average homelaber/HN reader if you're willing to spend a few hours of research, but importantly you would want to evaluate them as an array/bulk, not individually in that instance, else you lose context. That also typically requires a total monetary investment beyond what most homelabbers/consumers/prosumers are willing to invest even if the end-of-the-day TB/$ ratio ends up quite competitive. There's also many many types of flash drives (well beyond just MLC/TLC/QLC), and there's a huge difference between no names, white labels, and budget ADATA's and the like, and an actual proper high end/enterprise SSD (and a whole spectrum in between). And No, 990/9100 Pro's from Samsung and other similar prosumer drives are not high end flash. Good enough for home gamers and most prosumers, absolutely! They would also likely yield significant improvements vs these levens in OP. I'm not trying to say those prosumer drives are bad drives. They aren't (The levens though, even new in box, absolutely are). I'm merely saying that a small sample of some of the worst drives you can buy that are already beyond their stated wear and tear is frankly a poor sample to derive any real informed opinion on flash's potential or abilities. TL;DR: This really doesn't tell us much other than "bad flash is bad flash".
ksec 1y ago
That is basically saying dont store your data on USB Memory. Are there any way we could fix those corrupted bit flip files with USB Flash?
asdefghyk 1y ago
I wonder how ssd endurance is effected - if at all , by storage temperature. I’m thinking if it was kept at 3 degrees or even colder like frozen. Since chemical reactions proceed slower with a lower temperature. Photographic negatives can have deterioration greatly slowed if stored at some low temperatures. Would need to take steps to avoid condensation. … Would be interesting to know for hard drives to ….

123 points by progval 1y ago

For long term storage, prefer hard drives (careful about CMR vs SMR) If you have specific random IO high performance needs, you can either - get a SLC drive like https://news.solidigm.com/en-WW/230095-introducing-the-solidigm-d7-p5810-an-ultra-fast-slc-ssd-for-write-intensive-workloads https://news.solidigm.com/en-WW/230095-introducing-the-solid... - make one yourself by hacking the firmware: https://news.ycombinator.com/item?id=40405578 https://news.ycombinator.com/item?id=40405578 Be careful when you use something "exotic", and do not trust drives that are too recent to be fully tested: I learned my lesson for M2 2230 drives https://www.reddit.com/r/zfs/comments/17pztue/warning_you_may_want_to_avoid_some_western/ https://www.reddit.com/r/zfs/comments/17pztue/warning_you_ma... which seems validated by the large numbers of similar experiences like https://github.com/openzfs/zfs/discussions/14793 https://github.com/openzfs/zfs/discussions/14793

dragontamer 1y ago
If you care about long term storage, make a NAS and run ZFS scrub (or equivalent) every 6 months. That will check for errors and fix them as they come up. All error correction has a limit. If too many errors build up, it becomes unrecoverable errors. But as long as you reread and fix them within the error correction region, it's fine.
- csdvrx 1y ago
  > run ZFS scrub (or equivalent) every 6 months zfs in mirror mode offers redundancy at the block level but scrub requires plugging the device > All error correction has a limit. If too many errors build up, it becomes unrecoverable errors There are software solutions. You can specify the redundancy you want. For long term storage, if using a single media that you can't plug and scrub, I recommend par2 (https://en.wikipedia.org/wiki/Parchive?useskin=vector https://en.wikipedia.org/wiki/Parchive?useskin=vector) over NTFS: there are many NTFS file recovery tools, and it shouldn't be too hard to roll your own solution to use the redundancy when a given sector can't be read
- WalterGR 1y ago
  What hardware, though? I want to build a NAS / attached storage array but after accidentally purchasing an SMR drive[0] I’m a little hesitant to even confront the project. A few tens of TBs. Local, not cloud. [0] Maybe 7 years ago. I don’t know if anything has changed since, e.g. honest, up-front labeling. [0*] For those unfamiliar, SMR is Shingled Magnetic Recording. https://en.m.wikipedia.org/wiki/Shingled_magnetic_recording https://en.m.wikipedia.org/wiki/Shingled_magnetic_recording
  - 3np 1y ago
    Toshi Nx00/MG/MN are good picks. The company never failed us and I don't believe they've had the same kinds of controversies as the US competition. Please don't tell everyone so we can still keep buying them? ;)
  - wmf 1y ago
    Nothing can really save you from accidentally buying the wrong model other than research. For tens of TBs you can use either 4-8 >20TB HDDs or 6-12 8TB SSDs (e.g. Asustor). The difference really comes down to how much you're willing to pay.
  - matheusmoreira 1y ago
    > What hardware, though? Good question. There seems to be no way to tell whether or not we're gonna get junk when we buy hard drives. Manufacturers got caught putting SMR into NAS drives. Even if you deeply research things before buying, everything could change tomorrow. Why is this so hard? Why can't we have a CMR drive that just works? That we can expect to last for 10 years? That properly reports I/O errors to the OS?
  - code_biologist 1y ago
    The Backblaze Drive Stats are always a good place to start: https://www.backblaze.com/blog/backblaze-drive-stats-for-2024/ https://www.backblaze.com/blog/backblaze-drive-stats-for-202... There might be SMR drives in there, but I suspect not.
  - dragontamer 1y ago
    SMR will store your data, just slowly. It was a mistake for the Hard Drive business community to push them so hard IMO. But these days the 20TB+ drives are all HAMR or other heat/energy assisted tech. If you are buying 8TB or so, just make sure to avoid SMR but otherwise you're fine. Even then, SMR stores data fine, it's just really really slow.
- ErneX 1y ago
  I use TrueNAS and it does a weekly scrub IIRC.
AshamedCaptain 1y ago
> (careful about CMR vs SMR) Given the context of long term storage... why?
- 0cf8612b2e1e 1y ago
  After I was bamboozled with a SMR drive, always great to just make the callout to those who might be unaware. What a piece of garbage to let vendors upsell higher numbers. (Yes, I know some applications can be agnostic to SMR, but it should never be used in a general purpose drive).
- whoopdedo 1y ago
  Untested hypothesis, but I would expect the wider spacing between tracks in CMR makes it more resilient against random bit flips. I'm not aware of any experiments to prove this and it may be worth doing. If the HD manufacture can convince us that SMR is just as reliable for archival storage it would help them sell those drives since right now lots of people are avoiding SMR due to poor performance and the infamy of the bait-and-switch that happened a few years back.
sitkack 1y ago
Tape is extremely cheap now. I booted up a couple laptops that have been sitting unpowered for over 7 years and the sata SSD in one of them has missing sectors. It had zero issues when shutdown.
- seszett 1y ago
  Is tape actually cheap? Tape drives seem quite expensive to me, unless I don't have the right references.
  - wtallis 1y ago
    Tapes are cheap, tape drives are expensive. Using tape for backups only starts making economic sense when you have enough data to fill dozens or hundreds of tapes. For smaller data sets, hard drives are cheaper.
    - AStonesThrow 1y ago
      HDDs are a pragmatic choice for “backup” or offline storage. You’ll still need to power them up, just for testing, and also so the “grease” liquefies and they don’t stick. Up through 2019 or so, I was relying on BD-XL discs, sized at 100GB each. The drives that created them could also write out M-DISC archival media, which was fearsomely expensive as a home user, but could make sense to a small business. 100GB, spread over one or more discs, was plenty of capacity to save the critical data, if I were judiciously excluding disposable stuff, such as ripped CD audio.
    - sitkack 1y ago
      Used LTO5+ drives are incredibly cheap, you can get a whole tape library with two drives and many tape slots for under 1k. Tapes are also way more reliable than hard drives.
  - dogma1138 1y ago
    If you don’t have a massive amount of data to backup, used LTO5/6 drives are quite cheap, software and drivers is another issue however with a lot of enterprise kit. The problem ofc is that with a tape you need to also have a backup tape drive on hand. Overall if you get a good deal you can have a reliable backup setup for less than $1000 with 2 drives and a bunch of tape. But this is only good if you have single digit of TBs or low double digit of TBs to backup since it’s slow and with a single tape drive you’ll have to swap tapes manually. LTO5 is 1.5TB and LTO6 is 2.5TB (more with compression) it should be enough for most people.
vlovich123 1y ago
> - make one yourself by hacking the firmware: https://news.ycombinator.com/item?id=40405578 https://news.ycombinator.com/item?id=40405578 Be careful when you use something "exotic", and do not trust drives that are too recent to be fully tested Do you realize the irony of cautioning about buying off the shelf hardware but recommending hacking firmware yourself?
- userbinator 1y ago
  That "firmware hack" is just enabling an option that manufacturers have always had (effectively 100% "SLC cache") but almost always never use for reasons likely to do with planned obsolescence.
  - vlovich123 1y ago
    Converting a QLC chip into an SLC is not planned obsolescence. It’s a legitimate tradeoff after analyzing the marketplace that existing MTBF write lifetimes are within acceptable consumer limits and consumers would rather have more storage. Edit: and to preempt the “but make it an option”. That requires support software they may not want to build and support requests from users complaining that toggling SLC mode lost all the data or toggling QLC mode back on did similarly. It’s a valid business decision to not support that kind of product feature.
    - Dylan16807 1y ago
      And for the vast majority of use cases, even if QLC wears out TLC would be fine indefinitely. Limiting it to SLC capacity would be ridiculous.
    - userbinator 1y ago
      I have USB drives with good old SLC flash, whose data is still intact after several decades (rated for retention of 10 years at 55C after 100K cycles - and they have not been cycled anywhere near that much.) and consumers would rather have more storage No one from the manufacturers tells them that the "more storage" - multiplicatively more - lasts exponentially less. For the same price, would you rather have a 1TB drive that will retain data for 10 years after having written 100PB, or a 4TB one that will only hold that data for 3 months after having written 2PB? That requires support software they may not want to build The software is already there if you know where to look. and support requests from users complaining that toggling SLC mode lost all the data or toggling QLC mode back on did similarly Do they also get support requests from users complaining that they lost all data after reformatting the drive? It’s a valid business decision to not support that kind of product feature. The only "valid business decision" is to make things that don't last as long, so recurring revenue is guaranteed. Finally, the "smoking gun" of planned obsolescence: SLC flash requires nowhere near as much ECC and thus controller/firmware complexity as MLC/TLC/QLC. It is also naturally faster. The NRE costs of controllers supporting SLC flash is a fraction of those for >1 bit per cell flash. QLC in particular, according to one datasheet I could find, requires ECC that can handle a bit error rate of 1E-2. One in a hundred bits read will be incorrect in normal operation of a QLC storage device. That's how idiotic it is --- they're operating at the very limits of error correction, just so they can have a measly 4x capacity increase over SLC which is nearly perfect and needs very minimal ECC. All this energy and resource usage dedicated to making things more complex and shorter-lasting can't be considered anything other than planned obsolescence. Contrast this with SmartMedia, the original NAND flash memory card format, rated for 100K-1M cycles, using ECC that only needs to correct at most 1 bit in 2048, and with such high endurance that it doesn't even need wear leveling. Also consider that SLC drives should cost a little less than 4x the price of QLC ones of the same capacity, given the lower costs of developing controllers and firmware, and the same price of NAND die, yet those rare SLC drives which are sold cost much more --- they're trying to price them out of reach of most people, given how much better they actually are.

rkagerer 1y ago

I would never buy a no-name SSD. Did it once long ago and got bit, wrote a program to sequentially write a pseudorandom sequence across the whole volume then read back and verify, and proved all 8 Pacer SSD's I had suffered corruption.

WalterGR 1y ago
That’s also fairly common for cheap ‘thumb drives’, as I understand it. I’ve been bitten by that before. (Edit: Allegedly if you use low-numbered storage blocks you’ll be okay, but the advertised capacity (both packaging and what it reports to OS) is a straight-up lie.)
- WalterGR 1y ago
  (Edit: Retail packaging, I mean. Too late to edit my comment.)

gnabgib 1y ago

Discussion on the original source: (20 points, 3 days ago, 5 comments) https://news.ycombinator.com/item?id=43702193 https://news.ycombinator.com/item?id=43702193 Related: SSD as Long Term Storage Testing (132 points, 2023, 101 comments) https://news.ycombinator.com/item?id=35382252 https://news.ycombinator.com/item?id=35382252

bityard 1y ago

I didn't think it was controversial that SSDs are terrible at long term storage?

wmf 1y ago
I wouldn't say it's controversial but I suspect most people don't know about it. There's been a lot of discussion about SSD write endurance but almost none about retention.
creatonez 1y ago
Right, but the news is that someone finally actually tested the unplugged-is-worse theory in a long term real world test. So much of the existing data about SSD endurance has been exclusively SSDs in datacenters plugged in 24/7, so it's nice to see some data showing what the difference actually looks like.

jeffbee 1y ago

Endurance is proportional to programming temperature. In the video, when all four SSDs are installed at once, the composite device temperature ranges over 12º. This should be expected to influence the outcomes.

ein0p 1y ago

This is a known issue. You have to power up your SSDs (and flash cards, which are based on even more flimsy/cost optimized version of the same tech) every now and then for them to keep data. SSDs are not suitable for long term cold storage or archiving. Corollary: don't lose that recovery passphrase you've printed out for your hardware crypto key, the flash memory in it is also not eternal.

RicoElectrico 1y ago
Please explain to me how is that supposed to work. For all I know the floating gate is, well, isolated and only writes (which SSDs don't like if they're repeated on the same spot) touch it through mechanisms not unlike MOSFET aging i.e. carrier injection. Reading on the other hand depends on the charge in floating gate altering Vt of the transistor below, this action not being able to drain any charge from the floating gate.
- wmf 1y ago
  According to a local expert (ahem), leakage can occur through mechanisms like Fowler-Nordheim tunneling or Poole-Frenkel emission, often facilitated by defects in the oxide layers.
- ein0p 1y ago
  If you at least read the data from the drive from time to time, the controller will "refresh" the charge by effectively re-writing data that can't be read without errors. Controllers will also tolerate and correct _some_ bit flips on the fly, topping up cells, or re-mapping bad pages. Think of it as ZFS scrub, basically, except you never see most of the errors.
jsheard 1y ago
A not-so-fun fact is that this even applies to modern read-only media, most notably Nintendo game carts. Back in the day they used mask ROMs which ought to last more or less forever, but with the DS they started using cheaper NOR or NAND flash for larger games, and then for all games with the 3DS onwards. Those carts will bit-rot eventually if left unpowered for a long time.

jauntywundrkind 1y ago

Note: the worn drives were very worn. 128GB drive with 280TB written is ~2400 cycles. >5x it's 480x rating! Even though it's a cheap drive, it's rated endurance wasn't really that low. 600 cycles (1200TBW/2TB) is pretty common for consumer SSD: that's higher than 480x but not vastly higher. Glad folks are chiming in with the temperature sensitivity notes. I have parts coming in for a much bigger home-cloud system, and was planning on putting it in the attic. But it's often >110°F in the summer up there! I don't know how much of a difference that would make, given that the system will be on 24/7; some folks seem to say having it powered on should be enough, others note that usually it's during read that cells are refreshed. Doing an annual dd if=/nvme0n1 of=/dev/zero bs=$((1024*1024)) hadn't been the plan, but maybe it needs to be!

ilikepi 1y ago
Ok I gotta ask...why of=/dev/zero and not of=/dev/null ?
- jauntywundrkind 1y ago
  That's probably much better, oops!
  - gruez 1y ago
    You don't even need dd since you're reading the whole file end to end. Something like cat /dev/nvme0n1 > /dev/null would suffice.
ahofmann 1y ago
Just my 2 cents: I've installed quite a few servers and racks of hardware in very unsuitable spaces. LTO drives in dusty rooms, important disks in hot and cold (summer and winter), dusty and vibrating rooms and so on. I was very worried about them dying way sooner than people would expect. The only thing that died after two years was the LTO drives. Everything else is still running. So I wouldn't worry much about your hot attic. 43° Celsius outside means constantly over 50° inside the server, which sounds horrible but in the last 15 years of my experience nothing died because the room was too hot, or cold, or humid, or shaky. I've installed dust Filters in front of all air intakes, though. My reasoning is, that dust kills way faster than temperature.

stego-tech 1y ago

I mean, this reads as I expected it to: SSDs as cold storage are a risky gamble, and the longer the drive sits unpowered (and the more use it sees over its life), the less reliable it becomes. Man, I’d (figuratively) kill for a startup to build a prosumer-friendly LTO drive. I don’t have anywhere near the hardware expertise myself, but I’d gladly plunk down the dosh for a drive if they weren’t thousands of dollars. Prosumers and enthusiasts deserve shelf-stable backup solutions at affordable rates.

0manrho 1y ago
I agree with the general sentiment, but just a headsup for those who might be unaware... > thousands of dollars I know this varies a lot based on location, but if you're stateside, you can get perfectly functional used LTO6 drives for $200-$500 that support 6TB RW cartridges that you can still buy new for quite cheap (20pk of 6TB RW LTO6 carts[0] for $60), much cheaper than any other storage medium I'm aware of and still reasonably dense and capacious still by modern standards. Sure it's 3-4 generations behind the latest LTO's, and you might need to get yourself a SAS HBA/AIC to plug it in to a consumer system (those are quite cheap as well, don't need to get a full RAID controller), but all in that's still quite an affordable and approachable cold storage solution for prosumers. Is there a reason this wouldn't work for you? Granted, the autoloader/enclosed library units are still expensive as all hell, even the hold ones, and I'd recommend sticking to quantum over IBM/HPE for the drives given how restrictive the later can be over firmware/software, but just wanted to put it out there that you don't necessarily need to spend 4 figures to get a perfectly functional tape solution with many many TB's worth of storage. 0: https://buy.hpe.com/us/en/storage/storage-media/tape-media/lto-ultrium-cartridges/hpe-lto%E2%80%916-ultrium-6-25tb-rw-custom-labeled-20-data-cartridges-library-pack-without-cases/p/c7976ac https://buy.hpe.com/us/en/storage/storage-media/tape-media/l...
- throwaway81523 1y ago
  LTO6 capacity is 2.5TB. 6TB is "compressed" which these days is near worthless because data collections that size are likely to already compressed (example: video). If the idea is to back up a hard drive, it's not nice to require big piles of tape to do it. Right now even the current LTO generation (LTO9, 18TB native capacity) can't back up the current highest capacity hard drives (28TB or more, not sure). In fact HDD is currently cheaper per TB (20GB drive at $229 at Newegg) than LTO6 tape ($30 for 2.5TB) even if the tape drive is free. LTO would be interesting for regular users if the current generation drive cost $1000 or less new with warranty rather than as crap from ebay. It's too much of an enterprise thing now. Also I wonder what is up with LTO tape density. IBM 3592 drives currently have capacity up to 50TB per tape in a cartridge the same size as an LTO cartridge, so they are a couple generations ahead of LTO. Of course that stuff is even more ridiculously expensive.

0manrho 1y ago

Not surprsing. Flash is for hot/warm storage, not for cold storage, but using literal bottom of the bargin-bin barrel no-name drives that are already highly worn really doesn't tell us anything. Even if these were new or in powered on systems for their whole life, I wouldn't have high confidence in their data retention, reliability or performance quite frankly. Granted, there is something to be said about using budget/used drives en masse and brute forcing your way to reliability/performance/capacity on a budget through shear scale, but that requires some finesse and understanding of storage array concepts, best-practices, systems and software. By no means beyond the skills of an average homelaber/HN reader if you're willing to spend a few hours of research, but importantly you would want to evaluate them as an array/bulk, not individually in that instance, else you lose context. That also typically requires a total monetary investment beyond what most homelabbers/consumers/prosumers are willing to invest even if the end-of-the-day TB/$ ratio ends up quite competitive. There's also many many types of flash drives (well beyond just MLC/TLC/QLC), and there's a huge difference between no names, white labels, and budget ADATA's and the like, and an actual proper high end/enterprise SSD (and a whole spectrum in between). And No, 990/9100 Pro's from Samsung and other similar prosumer drives are not high end flash. Good enough for home gamers and most prosumers, absolutely! They would also likely yield significant improvements vs these levens in OP. I'm not trying to say those prosumer drives are bad drives. They aren't (The levens though, even new in box, absolutely are). I'm merely saying that a small sample of some of the worst drives you can buy that are already beyond their stated wear and tear is frankly a poor sample to derive any real informed opinion on flash's potential or abilities. TL;DR: This really doesn't tell us much other than "bad flash is bad flash".

ksec 1y ago

That is basically saying dont store your data on USB Memory. Are there any way we could fix those corrupted bit flip files with USB Flash?

asdefghyk 1y ago

I wonder how ssd endurance is effected - if at all , by storage temperature. I’m thinking if it was kept at 3 degrees or even colder like frozen. Since chemical reactions proceed slower with a lower temperature. Photographic negatives can have deterioration greatly slowed if stored at some low temperatures. Would need to take steps to avoid condensation. … Would be interesting to know for hard drives to ….