Re: Alternative to Optical Storage????

From	Paul <nospam@needed.invalid>
Newsgroups	comp.os.linux.advocacy, comp.os.linux.misc, alt.os.linux
Subject	Re: Alternative to Optical Storage????
Date	2024-09-29 17:18 -0400
Organization	A noiseless patient Spider
Message-ID	<vdcg84$1srul$1@dont-email.me> (permalink)
References	(2 earlier) <vd6q9i$24lio$1@gwaiyur.mb-net.net> <vd7man$uh1c$1@dont-email.me> <vdas1u$1l9vg$1@dont-email.me> <vdb6il$1mt37$1@dont-email.me> <vdcd0m$1se5e$1@dont-email.me>

Cross-posted to 3 groups.

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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.

   Paul

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Thread

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???? 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???? Robert Riches <spamtrap42@jacob21819.net> - 2024-10-02 03:28 +0000
                Re: Alternative to Optical Storage???? "186282@ud0s4.net" <186283@ud0s4.net> - 2024-10-02 21:50 -0400
                Re: Alternative to Optical Storage???? Steve Hayes <hayesstw@telkomsa.net> - 2024-10-03 06:40 +0200
                Re: Alternative to Optical Storage???? CrudeSausage <crude@sausa.ge> - 2024-10-03 09:58 -0400
                Re: Alternative to Optical Storage???? Steve Hayes <hayesstw@telkomsa.net> - 2024-10-04 04:46 +0200
                Re: Alternative to Optical Storage???? Paul <nospam@needed.invalid> - 2024-10-04 02:19 -0400
                Re: Alternative to Optical Storage???? Steve Hayes <hayesstw@telkomsa.net> - 2024-10-04 09:56 +0000
                Re: Alternative to Optical Storage???? The Natural Philosopher <tnp@invalid.invalid> - 2024-10-04 12:45 +0100
                Re: Alternative to Optical Storage???? Steve Hayes <hayesstw@telkomsa.net> - 2024-10-05 06:46 +0200
                Re: Alternative to Optical Storage???? Paul <nospam@needed.invalid> - 2024-10-04 11:16 -0400
                Re: Alternative to Optical Storage???? CrudeSausage <crude@sausa.ge> - 2024-10-04 08:34 -0400
                Re: Alternative to Optical Storage???? Paul <nospam@needed.invalid> - 2024-10-04 11:29 -0400
                Re: Alternative to Optical Storage???? Steve Hayes <hayesstw@telkomsa.net> - 2024-10-05 06:57 +0200
                Re: Alternative to Optical Storage???? Steve Hayes <hayesstw@telkomsa.net> - 2024-10-05 06:50 +0200
                Re: Alternative to Optical Storage???? Joel <joelcrump@gmail.com> - 2024-10-05 00:57 -0400
                Re: Alternative to Optical Storage???? Joel <joelcrump@gmail.com> - 2024-10-05 01:23 -0400
                Re: Alternative to Optical Storage???? "Jeff Gaines" <jgnewsid@outlook.com> - 2024-10-05 07:13 +0000
                Re: Alternative to Optical Storage???? Joel <joelcrump@gmail.com> - 2024-10-05 03:33 -0400
                Re: Alternative to Optical Storage???? "Jeff Gaines" <jgnewsid@outlook.com> - 2024-10-05 08:42 +0000
                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???? Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2024-10-03 15:34 +0000
          Re: Alternative to Optical Storage???? Rich <rich@example.invalid> - 2024-10-03 17:13 +0000
            Re: Alternative to Optical Storage???? "186282@ud0s4.net" <186283@ud0s4.net> - 2024-10-03 23:31 -0400
              Re: Alternative to Optical Storage???? Paul <nospam@needed.invalid> - 2024-10-04 02:12 -0400
              Re: Alternative to Optical Storage???? Steve Hayes <hayesstw@telkomsa.net> - 2024-10-05 07:01 +0200
                Re: Alternative to Optical Storage???? Paul <nospam@needed.invalid> - 2024-10-05 07:41 -0400
                Re: Alternative to Optical Storage???? Lars Poulsen <lars@cleo.beagle-ears.com> - 2024-10-05 21:03 +0000
                Re: Alternative to Optical Storage???? Lars Poulsen <lars@cleo.beagle-ears.com> - 2024-10-05 20:52 +0000
          Re: Alternative to Optical Storage???? Nux Vomica <nv@linux.rocks> - 2024-10-03 19:13 +0000
            Re: Alternative to Optical Storage???? "186282@ud0s4.net" <186283@ud0s4.net> - 2024-10-04 00:35 -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???? "186282@ud0s4.net" <186283@ud0s4.net> - 2024-10-04 01:04 -0400
  Re: Alternative to Optical Storage???? Rich <rich@example.invalid> - 2024-09-27 17:36 +0000
    Re: Alternative to Optical Storage???? Shadow <Sh@dow.br> - 2024-09-27 15:39 -0300
      Re: Alternative to Optical Storage???? jjb <jjb@invalid.invalid> - 2024-09-27 21:54 +0200
        Re: Alternative to Optical Storage???? Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2024-09-27 20:38 +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???? ant@zimage.comANT (Ant) - 2024-09-28 23:14 +0000
          Re: Alternative to Optical Storage???? Lars Poulsen <lars@beagle-ears.com> - 2024-09-29 13:25 -0700
            Re: Alternative to Optical Storage???? ant@zimage.comANT (Ant) - 2024-09-30 00:15 +0000
              Re: Alternative to Optical Storage???? candycanearter07 <candycanearter07@candycanearter07.nomail.afraid> - 2024-09-30 19:40 +0000
                Re: Alternative to Optical Storage???? ant@zimage.comANT (Ant) - 2024-10-01 05:35 +0000
                Re: Alternative to Optical Storage???? Lars Poulsen <lars@beagle-ears.com> - 2024-10-02 19:14 -0700
                Re: Alternative to Optical Storage???? ant@zimage.comANT (Ant) - 2024-10-04 05:05 +0000
                Re: Alternative to Optical Storage???? candycanearter07 <candycanearter07@candycanearter07.nomail.afraid> - 2024-10-03 16:00 +0000
            Re: Alternative to Optical Storage???? ant@zimage.comANT (Ant) - 2024-09-30 00:15 +0000
    Re: Alternative to Optical Storage???? Borax Man <rotflol2@hotmail.com> - 2024-10-01 10:33 +0000
  Re: Alternative to Optical Storage???? Nux Vomica <nv@linux.rocks> - 2024-09-28 10:46 +0000
  Re: Alternative to Optical Storage???? Nux Vomica <nv@linux.rocks> - 2024-09-28 11:04 +0000
    Re: Alternative to Optical Storage???? Nux Vomica <nv@linux.rocks> - 2024-09-28 13:24 +0000
  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

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