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Re: Alternative to Optical Storage????

Cross-posted to 3 groups.

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On 9/29/24 5:18 PM, Paul wrote:
> On Sun, 9/29/2024 4:23 PM, Lars Poulsen wrote:
>> On 29/09/2024 02:27, Paul wrote:
>>> The faster that storage devices get, the more sensitive they
>>> become to details. This is why I would keep you well away
>>> from my PCIe Rev5 NVMe at 14000/12000 MB/sec. That still
>>> needs an error corrector, and somehow keep up with the
>>> need to correct every sector being read out. It's one
>>> of the reasons those get so hot (and they put toy heatsinks
>>> on top).
>>>
>>> That's also how you can have devices like this. You would not
>>> get these sorts of rates, without IOPs in the picture to help.
>>>
>>> https://www.anandtech.com/show/21486/highpoint-updates-nvme-raid-cards-for-pcie-50-50-gbps-directattached-ssd-storage
>>
>> So SSDs are safe for long term storage (say, a decade?), even if you don't access them, so long as you keep them powered on?
>>
> 
> We don't know all the details of the firmware fixes, but
> at least in one case where the TLC used to get "mushy", the
> fix for that was selective rewriting of some kind, to "refresh"
> the device. That might have been a Samsung.
> 
> They don't give us constant estimates of archival life, leaving
> us to "guess" the number is ten years. After all, it takes
> ten years to test :-)
> 
> NOR flash chips used to get Bit Rot, between 10 and 20 years,
> but that's an example of a device with no error correction
> at all. The error correction in an SSD, is "mondo-powerful",
> but, it assumes random degradations, not correlated ones.
> If all the floating gates head to zero volts, an ECC
> can't save you then. It is the archival case, that (eventually)
> has to fail.
> 
> It's like the Helium disk drives in a sense. We know Helium
> will eventually all leak out of the drive. There is no spigot
> on the side for refilling them. If I put a 22TB drive inside
> a time capsule glass bottle, come back in 40 years, it's
> a good assumption the drive will not start. Some of the drives
> have a pressure sensor (it's been spotted in SMART but is
> not documented). We know then, from "ground truth", a Helium drive
> is not archival quality. All we can argue about, is what year
> all the helium will be gone. The guarantee is for five years,
> but this is not a measured quantity, and if there was any
> significant field failure rate attributable to no gas left,
> it hasn't made the news yet. But the details of the design,
> tell you the gas cannot last forever (it is retained by a
> "thick adhesive", not by a gas-tight tin -- clever
> people did this). The drives have two lids, the inner lid
> secured with adhesive (gas "tight"), the outer welded lid
> mechanically protects the inner lid from "finger pokes".
> The welded lid is not gas tight. The welds do not really
> need to be all that fancy.
> 
> The flash is the same way then. We know the floating gates,
> even though disallowed, the electrons will eventually leave,
> and we will be left with a "deflated feeling". If you did
> happen to power up the device once a year, and (somehow)
> the device notices a high error corrector rate, it might
> choose to rewrite the sectors behind your back. I'd leave
> it powered over night, while it catches up on house cleaning.
> 
> That's for TLC or QLC. The SLC and MLC drives, might not
> even have that chunk of code, for their maintenance. If they
> had the code, and the TLC or QLC ones had inherited the code,
> we would not have noticed a thing. The fact someone had to
> add code, tells you the SLC and MLC rely on the quality of the
> floating gates, to make it to ten years. Based on the NOR flash
> getting the odd bit corrupted at, say, 15 years, gives you
> some idea about how well the SLC device may hold up. At fifteen
> years, it can use its error corrector and hide those not
> very dense failures. Since TLC and QLC are constantly
> using their error correctors, the behavior is not the same.
> 
> Would accelerated life testing be valid for TLC or QLC archival
> parameters ? Dunno. All we know is, the physics are the same
> for the floating gate, but the thresholds are a lot tighter
> on the SSDs you and I own, and there HAS to be a consequence
> to this. The archival just cannot be as good... unless you
> power them occasionally and let them sweep the dust under
> the rug. The ECC can count the number of bits in error in
> the sector, and based on that, it knows how close to
> "uncorrectable" it is getting -- if the power is on.
> Leave it in the back yard for 40 years, the cells will be
> flat, and rewrites, will not be possible.
> 
> I would say that 6TB air-breathing drives (state on the lid
> "do not cover this hole), those are archival material. I
> would expect to power one up 20 years from now, and it will work.
> That's why I own five or six of those, but I only own one
> Helium drive.
> 
> And with the right optical media choice (not the dye ones),
> those could be buried in the yard as well. Just keep the
> humidity down. You don't want any biological attacks
> on the media. Maybe some Verbatim Gold DVDs would be
> good yard material.


   "M-DISK"s are by far the best for archival. They
   do not use dyes, something closer to a 'mineral'
   layer the laser etches.

   Alas, as mentioned elsewhere in this thread, optical
   disks have LOW capacity by today's standards.

   For 10-years PLUS ... really NOT any great choices.
   It's a problem.

   The OTHER problem is devices/drivers for READING
   your old media. Presently the Smithsonian and
   Library Of Congress is FREAKIN' about this. The
   50s/60s especially saw SO many kinds/schemes of
   storage. The formats were often proprietary and
   poorly/not documented and the physical devices
   and interfaces were oft made for a very short time.

   I've got some 8-inch floppies ... where can I read
   THOSE ??? Old industrial removable-pack hard
   drives ??? The hardware just doesn't exist anymore.
   LOTS of govt/mil/NASA data on those old things ...

   SO ... REPLICATION ... keep MOVING yer data to the
   latest/greatest and 'cloud'. Stick to compression
   and encryption SURE to be supported really long term.

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Alternative to Optical Storage???? Nux Vomica <nv@linux.rocks> - 2024-09-27 16:37 +0000
  Re: Alternative to Optical Storage???? Joel <joelcrump@gmail.com> - 2024-09-27 12:40 -0400
    Re: Alternative to Optical Storage???? Ralf Schneider <schneiderr@freenet.de> - 2024-09-27 17:33 +0000
      Re: Alternative to Optical Storage???? Chris Ahlstrom <OFeem1987@teleworm.us> - 2024-09-27 15:05 -0400
      Re: Alternative to Optical Storage???? "Jeff Gaines" <jgnewsid@outlook.com> - 2024-09-27 21:06 +0000
      Re: Alternative to Optical Storage???? Paul <nospam@needed.invalid> - 2024-09-27 21:32 -0400
        Re: Alternative to Optical Storage???? Nux Vomica <nv@linux.rocks> - 2024-09-28 10:56 +0000
          Re: Alternative to Optical Storage???? Paul <nospam@needed.invalid> - 2024-09-28 07:41 -0400
          Re: Alternative to Optical Storage???? The Natural Philosopher <tnp@invalid.invalid> - 2024-09-28 12:57 +0100
        Re: Alternative to Optical Storage???? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-09-29 06:28 +0000
          Re: Alternative to Optical Storage???? Paul <nospam@needed.invalid> - 2024-09-29 05:27 -0400
            Re: Alternative to Optical Storage???? Lars Poulsen <lars@beagle-ears.com> - 2024-09-29 13:23 -0700
              Re: Alternative to Optical Storage???? Paul <nospam@needed.invalid> - 2024-09-29 17:18 -0400
                Re: Alternative to Optical Storage???? "186282@ud0s4.net" <186283@ud0s4.net> - 2024-09-30 01:34 -0400
                Re: Alternative to Optical Storage???? The Natural Philosopher <tnp@invalid.invalid> - 2024-09-30 12:29 +0100
                Re: Alternative to Optical Storage???? The Natural Philosopher <tnp@invalid.invalid> - 2024-09-30 12:25 +0100
                Re: Alternative to Optical Storage???? jjb <jjb@invalid.invalid> - 2024-09-30 16:41 +0200
                Re: Alternative to Optical Storage???? "186282@ud0s4.net" <186283@ud0s4.net> - 2024-10-01 01:29 -0400
                Re: Alternative to Optical Storage???? Steve Hayes <hayesstw@telkomsa.net> - 2024-10-03 06:40 +0200
                Re: Alternative to Optical Storage???? Paul <nospam@needed.invalid> - 2024-09-30 19:34 -0400
              Re: Alternative to Optical Storage???? The Natural Philosopher <tnp@invalid.invalid> - 2024-09-30 11:57 +0100
            Re: Alternative to Optical Storage???? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-09-30 01:49 +0000
    Re: Alternative to Optical Storage???? Steve Hayes <hayesstw@telkomsa.net> - 2024-10-01 07:04 +0200
      Re: Alternative to Optical Storage???? Joel <joelcrump@gmail.com> - 2024-10-01 01:08 -0400
      Re: Alternative to Optical Storage???? Paul <nospam@needed.invalid> - 2024-10-01 03:10 -0400
        Re: Alternative to Optical Storage???? "186282@ud0s4.net" <186283@ud0s4.net> - 2024-10-03 01:47 -0400
        Re: Alternative to Optical Storage???? "186282@ud0s4.net" <186283@ud0s4.net> - 2024-10-03 02:28 -0400
          Re: Alternative to Optical Storage???? Paul <nospam@needed.invalid> - 2024-10-03 03:10 -0400
      Re: Alternative to Optical Storage???? Zach Standig <zstandig@kmbs.konicaminolta.us> - 2024-10-01 15:51 -0400
  Re: Alternative to Optical Storage???? Rich <rich@example.invalid> - 2024-09-27 17:36 +0000
    Re: Alternative to Optical Storage???? Nux Vomica <nv@linux.rocks> - 2024-09-27 20:26 +0000
      Re: Alternative to Optical Storage???? not@telling.you.invalid (Computer Nerd Kev) - 2024-09-28 07:54 +1000
        Re: Alternative to Optical Storage???? Rich <rich@example.invalid> - 2024-09-28 01:49 +0000
      Re: Alternative to Optical Storage???? Lars Poulsen <lars@beagle-ears.com> - 2024-09-28 15:33 -0700
    Re: Alternative to Optical Storage???? Borax Man <rotflol2@hotmail.com> - 2024-10-01 10:33 +0000
  Re: Alternative to Optical Storage???? D <nospam@example.net> - 2024-09-28 00:13 +0200
    Re: Alternative to Optical Storage???? Nux Vomica <nv@linux.rocks> - 2024-09-28 10:46 +0000
      Re: Alternative to Optical Storage???? The Natural Philosopher <tnp@invalid.invalid> - 2024-09-28 12:44 +0100
      Re: Alternative to Optical Storage???? chrisv <chrisv@nospam.invalid> - 2024-09-28 07:55 -0500
  Re: Alternative to Optical Storage???? "186282@ud0s4.net" <186283@ud0s4.net> - 2024-09-27 22:18 -0400
  Re: Alternative to Optical Storage???? The Natural Philosopher <tnp@invalid.invalid> - 2024-09-28 07:33 +0100
    Re: Alternative to Optical Storage???? Nux Vomica <nv@linux.rocks> - 2024-09-28 11:04 +0000
      Re: Alternative to Optical Storage???? The Natural Philosopher <tnp@invalid.invalid> - 2024-09-28 13:04 +0100
        Re: Alternative to Optical Storage???? Nux Vomica <nv@linux.rocks> - 2024-09-28 13:24 +0000
          Re: Alternative to Optical Storage???? The Natural Philosopher <tnp@invalid.invalid> - 2024-09-28 14:45 +0100
  Re: Alternative to Optical Storage???? "186282@ud0s4.net" <186283@ud0s4.net> - 2024-09-29 00:43 -0400
    Re: Alternative to Optical Storage???? vallor <vallor@cultnix.org> - 2024-09-29 07:21 +0000
      Re: Alternative to Optical Storage???? "186282@ud0s4.net" <186283@ud0s4.net> - 2024-09-30 00:09 -0400
  Re: Alternative to Optical Storage???? "J.O. Aho" <user@example.net> - 2024-09-29 10:22 +0200
  Re: Alternative to Optical Storage???? Woozy Song <suzyw0ng@outlook.com> - 2024-09-29 17:47 +0800

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