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Flash media longevity testing – 6 years later

by 1970-01-01 on 3/8/26, 4:22 PM with 91 comments

• by ComputerGuru on 3/9/26, 4:34 PM

  Slightly related: I have a tool that writes random (incompressible) data to a disk and lets you verify it back without storing a copy (by using a csprng seed), initially developed for benchmarking SSDs that used to cheat to get better performance numbers but that can also be used for this purpose or to overwrite (“shred”) a disk: https://github.com/mqudsi/hddrand

• by ralferoo on 3/9/26, 4:53 PM

  I like the fact he's not just verifying all of them each year. AFAICR, reading the flash causes the row to be rewritten with the values just read.

  I remember years ago working on the Wii, and there was a restriction on how often you could read the flash to avoid premature wearing. Not sure if that was just the specific type of storage, as googling suggests that NAND is subject to this and NOR isn't. I think pretty much all USB drives now use NOR flash, so maybe this isn't actually an issue any more.

• by jofla_net on 3/9/26, 7:32 PM

  Buyer be warned i think this is extremely brand-dependent.

  While i've had generally solid experience with sandisk for almost 20 years and had a few old drives (which i hear are slc-based so its not surprising) hold files for over 5 years no issue, i recently almost lost over 4 years of photos.

  I had purchased some lexar drives from costco since they were dual interface (usb A / usb C) about 2 years ago, and it was usefull to just get some pictures off my phone. I usually don't rely on such a setup for long term but as with all things I was delayed tending to it. I figured there were 2 per box so i just copied them twice, and diffed them several times to make sure they were exact copies.

  After 24 months, one of the drives had a %95 loss, almost every picture was lost cut-off bottom half or so. The other drive surprisingly seemed fine, though it had been plugged in every 6-9 months I recall, as I wanted to browse it a few times, it seems that this action saved the volume. Upon further inspection the good drive still lost 10 pictures in about 5 thousand, so it wasn't perfect.

  Lexar.

  https://www.ebay.com/itm/176810492981?chn=ps&_trkparms=ispr%...

• by digdugdirk on 3/9/26, 5:10 PM

  What is the best consumer friendly long-term storage medium? Are we still better off with high capacity dvd/Blu ray discs?

• by ogurechny on 3/10/26, 2:53 AM

  I've been using an old Symbian phone with the same Class Not-That-Good SD card bought back then. In the early 2010s, I copied a lot of MP3 files and ebooks there, and used the camera to take photos occasionally. Then it was no longer used for music and other needs, and the files just rested there. After about 10 years, I've decided to play some music on the phone, and these tracks had a lot of skips and rattle. Images copied from the card showed a lot of damage, too. So when someone on the internet posts how SD cards are a cheap and compact long term storage, I am not impressed. You probably need to refresh all previously stored data with each monthly backup.

  It should be mentioned that the phone board often gets warm during operation or battery charging, and the temperature is stated an important harmful factor in a different comment.

  So if you have some old files on an old device, and assume that they are still there because their records in the file system still look fine, you might be surprised.

• by havaloc on 3/9/26, 9:36 PM

  I bought about 20 flash drives in 2019 at work to parcel out when needed, once or twice a quarter for users.

  I needed one last week, and had to throw most of them away, they had all died from presumably dormancy, even new in the package.

• by deltoidmaximus on 3/9/26, 6:52 PM

  Interesting related thread that includes SSD firmware engineer fairfeather discussing refresh mechanism implementation: https://news.ycombinator.com/item?id=46038099

• by monster_truck on 3/9/26, 4:27 PM

  Rewriting the data each year hides the actual issue here. Have had plenty of "nice" flash drives rot to hell in 18+ months of dormancy

• by quilombodigital on 3/10/26, 4:08 AM

  I was trying to roast this guy because I figured a burn-in test should accomplish the same thing he’s doing. But no... I had to ask the great oracle, GPT (General Purpose Truth), and it told me the guy is actually doing something worthwhile. How are trolls supposed to survive in this inhospitable era?

  Apparently, multi-year storage tests are still valuable for validating whether those estimates match reality. Who knew...

• by somat on 3/9/26, 6:00 PM

  On a related subject, physical media, like a song album. I started by wondering if there were ever any solid state distribution options (One Company tried SD cards) and then started digging into the underlying storage tech to see if I could find a write once long term stable process.

  First the elephant in the room. Why solid state? because the drives to read the media are often the weak link. When the drives are no longer being manufactured how hard is it to make one? reading solid state drives is a relatively low precision electrical process compared to the high precision mechanical process needed for most media.

  First on the chopping block was bulk storage. It tends to be delicate and hard to read and short lifespans. But if I limited myself to small storage there are some interesting options. fusible proms were promising but top out at a few megabytes. Mask roms? does anyone offer a mask rom service anymore?

  Put a mask rom into a sd card... no, sd cards are too physically small. For a song album we want something bigger to put album art on. A thing the size of the original gameboy cartridge with a usb interface and a mask rom?

  My conclusion, for that specific goal, indefinite future storage of a song album. Vinyl records. low tech enough that it is easy to make a player for them.

• by Cyphase on 3/10/26, 8:23 AM

  I saw "reddit.com" and my first thought was r/DataHoarder.

• by rambambram on 3/9/26, 6:52 PM

  I could google it, but I would rather ask HN: what are the best pens (or pen(cil)/paper-combination) for keeping written text as long as possible? I had some Stabilo pen which was very nice ergonomically, but the blue ink faded within a couple of years (laying on my window sil in the sun, but still).

  My guess is: regular graphite pencil on porous paper is best. Any ideas about further things I have to take into account?

• by nullorempty on 3/9/26, 4:44 PM

  What's the simplest way to rewrite the data without actually copying the data? Like in place rewrite - you write what you read.

• by jmakov on 3/9/26, 3:19 PM

  Powered all the time on or powered off?

• by shiroiuma on 3/10/26, 1:57 AM

  We really need that holographic data storage that they've been working on for decades now.

• by foxglacier on 3/9/26, 9:59 PM

  Beware that flash data lifetime is sensitive to temperature in the normal range people store stuff at. Store them in the roof space of your house that can exceed 40C each day and they might not last one year.

  Definitely not a medium to passively store anything long term without power! Use Hard drives or Blu-ray instead.

• by 01HNNWZ0MV43FF on 3/9/26, 4:41 PM

  That's good. I want to keep some institutional knowledge and photos in "cold storage" and cloud subscriptions with a credit card and password are completely inviable.

  I'll probably get a spinner and a flash drive and hope one of them survives the years.