Flash media longevity testing – 6 years later

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

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.

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?

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

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.

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

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

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

Powered all the time on or powered off?

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.

[dead]