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I back up important things on SLC USB-A flash drives and write refreshed copies at least annually. The drives are small (<=8GB), expensive, there are only a han

I back up important things on SLC USB-A flash drives and write refreshed copies at least annually. The drives are small (<=8GB), expensive, there are only a handful of manufacturers (mine's an ATP), and you're probably ordering it from Digikey or Mouser. SLC will supposedly hold data at rest longer, and USB-A means I can find readers for at least another decade. We'll see if retention at rest is actually good.

userbinator 2y ago
You can get (real!) SLC USB drives from Aliexpress too, for around $0.70/GB. These aren't the ultra-cheap ones which are often fake in capacity, but prominently advertise the type of flash and controller they use. I also have some really small USB drives from around 2 decades ago, of course SLC flash (the only type of NAND flash at the time), and can confirm that their data is still intact. They've gone through probably a few dozen full-drive writes, while SLC flash back then was rated for 10 years retention after 100K cycles.
- pdimitar 2y ago
  Yeah, I have 2 such from AliE and they perform well and haven't lost anything yet even though they have dozens of thousands of files at rest that are updated 1-2 times a month, for almost 3 years now. Quite pleased with them. They are indeed more expensive but nothing that a programmer salary would notice even if you bought 10 of them. I am wondering whether I should buy another pair and use it as a metadata mirrored vdev on my media NAS. Haven't decided yet.
  - dehrmann 2y ago
    > I am wondering whether I should buy another pair and use it as a metadata mirrored vdev on my media NAS. Haven't decided yet. Probably not worth the operational overhead, and in the past, I remember USB having significantly worse write latency than SATA.
    - pdimitar 2y ago
      Yeah, thought the same. Not to mention that I tried to have a bunch of old USB sticks put into one of my servers and it added like two minutes to its reboot time. (Though admittedly I didn't fight hard with systemd to make sure their mounting does not block anything -- it's likely possible to do.) Ultimately I am not willing to shell out hundreds of EUR for f.ex. 2x SLC internal SSDs at 32 or 64 GB each so I guess I'll just have a few spare disks around when I am back to being employed, and that's going to be that.

userbinator 2y ago

You can get (real!) SLC USB drives from Aliexpress too, for around $0.70/GB. These aren't the ultra-cheap ones which are often fake in capacity, but prominently advertise the type of flash and controller they use. I also have some really small USB drives from around 2 decades ago, of course SLC flash (the only type of NAND flash at the time), and can confirm that their data is still intact. They've gone through probably a few dozen full-drive writes, while SLC flash back then was rated for 10 years retention after 100K cycles.

pdimitar 2y ago
Yeah, I have 2 such from AliE and they perform well and haven't lost anything yet even though they have dozens of thousands of files at rest that are updated 1-2 times a month, for almost 3 years now. Quite pleased with them. They are indeed more expensive but nothing that a programmer salary would notice even if you bought 10 of them. I am wondering whether I should buy another pair and use it as a metadata mirrored vdev on my media NAS. Haven't decided yet.
- dehrmann 2y ago
  > I am wondering whether I should buy another pair and use it as a metadata mirrored vdev on my media NAS. Haven't decided yet. Probably not worth the operational overhead, and in the past, I remember USB having significantly worse write latency than SATA.
  - pdimitar 2y ago
    Yeah, thought the same. Not to mention that I tried to have a bunch of old USB sticks put into one of my servers and it added like two minutes to its reboot time. (Though admittedly I didn't fight hard with systemd to make sure their mounting does not block anything -- it's likely possible to do.) Ultimately I am not willing to shell out hundreds of EUR for f.ex. 2x SLC internal SSDs at 32 or 64 GB each so I guess I'll just have a few spare disks around when I am back to being employed, and that's going to be that.