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I use USB stick/thumb drives in STBs/PVRs and no doubt they take a thrashing when repeatedly recording TV programs. Like most of us, I've many of them and whils

I use USB stick/thumb drives in STBs/PVRs and no doubt they take a thrashing when repeatedly recording TV programs. Like most of us, I've many of them and whilst I try to keep the TV ones separate from those I use on my computers they often get mixed when I need one for my PC in a hurry. What I want to know is there any general purpose utility that is capable of testing a variety of brands of these devices and doing a decent assessment of their state/reliability? It seems that drive manufacturers don't provide much help here as I've not seen any such utilites for them. I raised this matter with a SanDisk rep at a trade show several years back and he said he didn't know of any. Same problem applies to SD cards (SDHC, SDXC, etc.), so any info on them would also be useful.

beardedscotsman 4y ago
Isn’t the problem with this, that they work till they fail. You can run some software that can tell you how dead the drive is, but you can’t figure how likely it will die. Some drives I think have some stats you can access, but generally you can’t tell until it fails. There used to be a great site before that was a data center publishing physical hdd stats, not looked for it for a long time, but I presume they would have ssd stats these days too.
- hilbert42 4y ago
  I think you're right about working until they fail but I've only ever had anecdotal evidence to this effect. I also reckon much of the problem comes from the fact that information about them is proprietary—simply manufacturerers just don't tell us much about them as to do so may reveal trade secrets. Several decades ago I was involved in work where we had to have as large storage as possible irrespective of cost, back then a 1GB SanDisk was worth somewhere between $1k and $2k (we replaced single-sep time lapse remote monitoring film cameras with TV and needed large storage). We approached SanDisk (about the only manufacturer with such large drives at the time) and they were very reticent about telling us anything worthwhile—even though we were a large international organization and had clout. We needed to know the reliability so we had to investigate it ourselves, whilst we made some progress it was never fully satisfactory. Anecdotal info we learned from various sources was that manufacturerers had ways of testing them by altering the threshold voltage—the point where the gate potential would switch from 0 to 1. At a critical point one could check how many gates failed to switch and this voltage altered over time/with use. Monitoring this could provide useful info such as knowing when to retire a device before it failed. How accurate this info is I don't know but it seems to make sense. If true, we users should be demanding of manufacturerers utilities that are capable of doing such testing. Trouble is, manufacturerers continue to maintain this secrecy. PS: several days ago I put a brand new SanDisk 128GB in one of my PVRs and it's really hot to touch even when it's on standby (not recording TV). This isn't the first time I've noticed how hot they get. This isn't the PVR's fault as I've several different brands and the thumb drive gets very hot in each one including my PC. One wonders what this elevated temperature does to the reliability/service life.
chasil 4y ago
An interesting thing about flash memory is that it can be rejuvenated if held at high temperature. Unfortunately, most plastic packaging precludes this. Solder connections would also be a problem. https://hardware.slashdot.org/story/12/12/02/2222235/self-healing-nand-flash-memory-that-can-survive-over-100-million-cycles https://hardware.slashdot.org/story/12/12/02/2222235/self-he...
- hilbert42 4y ago
  That's interesting, I have a 500GB Crucial SSD that's essentially new and it failed (it failed progressively over some days until the drive wasn't recognized). I've done everything to get the data off it as nothing I do can see the drive (it's no longer recognized as a SATA drive). It may be worthwhile heating it up in the oven and see what happens (I can control the temp pretty accurately). Take the case off first etc. If it falls apart or the solder melts nothing's lost over and above what's happened already.
  - chasil 4y ago
    I am betting that heat would also erase the memory.
    - hilbert42 4y ago
      Likely would methinks. But sometimes odd things happen - see my reply to a1369209993.
  - a1369209993 4y ago
    That's probably a bad idea. Unless I'm confusing it with a different storage technology, heating flash memory has the not-really-side effect of erasing the data on it. The reason it rejuvenates it is because that also erases most of the effects of wear. (Think writing and erasing on a piece of paper until it's unreadably covered in smeared half-erased pencil residue, then grinding the paper up into pulp and pouring a new sheet of paper.) It can't be worse than nothing, but it's unlikely to be any better. I'd recommend instead (or at least first) desoldering the component memory chips and trying to read the data off of them directly with a microcontoller (bit-banging whatever protocol the drive uses internally). It's more (and slower and fiddlier) work, but also more likely to get at least some data back.

beardedscotsman 4y ago

Isn’t the problem with this, that they work till they fail. You can run some software that can tell you how dead the drive is, but you can’t figure how likely it will die. Some drives I think have some stats you can access, but generally you can’t tell until it fails. There used to be a great site before that was a data center publishing physical hdd stats, not looked for it for a long time, but I presume they would have ssd stats these days too.

hilbert42 4y ago
I think you're right about working until they fail but I've only ever had anecdotal evidence to this effect. I also reckon much of the problem comes from the fact that information about them is proprietary—simply manufacturerers just don't tell us much about them as to do so may reveal trade secrets. Several decades ago I was involved in work where we had to have as large storage as possible irrespective of cost, back then a 1GB SanDisk was worth somewhere between $1k and $2k (we replaced single-sep time lapse remote monitoring film cameras with TV and needed large storage). We approached SanDisk (about the only manufacturer with such large drives at the time) and they were very reticent about telling us anything worthwhile—even though we were a large international organization and had clout. We needed to know the reliability so we had to investigate it ourselves, whilst we made some progress it was never fully satisfactory. Anecdotal info we learned from various sources was that manufacturerers had ways of testing them by altering the threshold voltage—the point where the gate potential would switch from 0 to 1. At a critical point one could check how many gates failed to switch and this voltage altered over time/with use. Monitoring this could provide useful info such as knowing when to retire a device before it failed. How accurate this info is I don't know but it seems to make sense. If true, we users should be demanding of manufacturerers utilities that are capable of doing such testing. Trouble is, manufacturerers continue to maintain this secrecy. PS: several days ago I put a brand new SanDisk 128GB in one of my PVRs and it's really hot to touch even when it's on standby (not recording TV). This isn't the first time I've noticed how hot they get. This isn't the PVR's fault as I've several different brands and the thumb drive gets very hot in each one including my PC. One wonders what this elevated temperature does to the reliability/service life.

chasil 4y ago

An interesting thing about flash memory is that it can be rejuvenated if held at high temperature. Unfortunately, most plastic packaging precludes this. Solder connections would also be a problem. https://hardware.slashdot.org/story/12/12/02/2222235/self-healing-nand-flash-memory-that-can-survive-over-100-million-cycles https://hardware.slashdot.org/story/12/12/02/2222235/self-he...

hilbert42 4y ago
That's interesting, I have a 500GB Crucial SSD that's essentially new and it failed (it failed progressively over some days until the drive wasn't recognized). I've done everything to get the data off it as nothing I do can see the drive (it's no longer recognized as a SATA drive). It may be worthwhile heating it up in the oven and see what happens (I can control the temp pretty accurately). Take the case off first etc. If it falls apart or the solder melts nothing's lost over and above what's happened already.
- chasil 4y ago
  I am betting that heat would also erase the memory.
  - hilbert42 4y ago
    Likely would methinks. But sometimes odd things happen - see my reply to a1369209993.
- a1369209993 4y ago
  That's probably a bad idea. Unless I'm confusing it with a different storage technology, heating flash memory has the not-really-side effect of erasing the data on it. The reason it rejuvenates it is because that also erases most of the effects of wear. (Think writing and erasing on a piece of paper until it's unreadably covered in smeared half-erased pencil residue, then grinding the paper up into pulp and pouring a new sheet of paper.) It can't be worse than nothing, but it's unlikely to be any better. I'd recommend instead (or at least first) desoldering the component memory chips and trying to read the data off of them directly with a microcontoller (bit-banging whatever protocol the drive uses internally). It's more (and slower and fiddlier) work, but also more likely to get at least some data back.