Re: R: Large discs (Was: Spectre & Meltdown

[Warner Losh via cctalk]

On Fri, Jan 5, 2018 at 1:13 PM, Fred Cisin via cctalk  wrote:

> On Fri, 5 Jan 2018, Mazzini Alessandro wrote:
>
>> I'm  not sure I would use SSD for long term "secure" storage, unless maybe
>> using enterprise level ones.
>> Consumer level SSD are, by specifics, guaranteed to retain data for 6
>> months
>>
>
The JEDEC spec for Consumer grade SSDs is 1 year unpowered at 30C at end of
life.
The JEDEC spec for Enterprise grade SSDs is 90 days, unpowered at 30C at
end of life.

As far as I've seen, all SATA and NVME drive vendors adhere to these specs
as a minimum, but there's also a new class of drive for 'cold storage'
which has high retention, but low endurance and longer data read times...


> if unpowered... any more time means being lucky. Would suck to save, store,
>> and after some years find the data mangled...
>>
>
> Yep!
> SSD would be very unsuitable for archiving.
>

Unworn (meaning only a few P/E cycles) SSDs made from MLC or SLC NAND have
data retention measured in the decade range. Stored at 0C, these would have
~300 year data retention since every 10C below the benchmark temperature
gives you 3x longer retention. Conversely, storing at 40C or 50C puts the
data at risk.

Worn (meaning near end of life) SSDs, especially those that have been
pushed past end of life, have issues.

But, it is a nice fast medium for short-term uses.
> AND, it MIGHT be the first to get a unit larger than 2TB that will fit in
> a thin 2.5" form factor.
> Probably better SHORT-TERM reliability than the Seagate 2TB thin SATA
> spinning rust.
>
>
> What is the archival life of a BDXL, other than M-disc?
> M-disc media is a bit expensive.
> It looks like an excellent medium for data collections a tenth the size of
> what I'm playing with.
>
>
> It seems that it is still necessary to maintain multiple copies
> (geographically separate - we had a 4.4 quake yesterday morning), on
> multiple different media, and make new copies on a regular basis.

Re: R: Large discs (Was: Spectre & Meltdown

[Fred Cisin via cctalk]

In cases where the source remains available, in case of problems, nothing 
can beat it for sneaker-net.  It does not contribute noticeably to the 
transfer speeds.



On Fri, 5 Jan 2018, Sam O'nella via cctalk wrote:
You're one of the first people I've heard quote that. Do you know where 
that is said? Years ago several friends and myself all picked up 64mb 
usb thumb drives so we could have multiple backups of a game and few 
other projects we were coding.  Maybe it was an extended period of time 
(we ended up switching to compatible removable drive bays) but 2 out of 
3 of us lost all the data on our thumb drives around the same time. 
I haven't heard may others share the concern but i wouldn't use ssd as a 
tech unless im forced to for that reason.



 Original message From: Mazzini Alessandro via cctalk  Date: 1/5/18  7:15 AM  (GMT-06:00) 
I'm  not sure I would use SSD for long term "secure" storage, unless maybe

using enterprise level ones.
Consumer level SSD are, by specifics, guaranteed to retain data for 6 months
if unpowered... any more time means being lucky. Would suck to save, store,
and after some years find (over snipped)

Re: R: Large discs (Was: Spectre & Meltdown

[Fred Cisin via cctalk]

On Fri, 5 Jan 2018, Mazzini Alessandro wrote:

I'm  not sure I would use SSD for long term "secure" storage, unless maybe
using enterprise level ones.
Consumer level SSD are, by specifics, guaranteed to retain data for 6 months
if unpowered... any more time means being lucky. Would suck to save, store,
and after some years find the data mangled...


Yep!
SSD would be very unsuitable for archiving.
But, it is a nice fast medium for short-term uses.
AND, it MIGHT be the first to get a unit larger than 2TB that will fit in 
a thin 2.5" form factor.
Probably better SHORT-TERM reliability than the Seagate 2TB thin SATA 
spinning rust.



What is the archival life of a BDXL, other than M-disc?
M-disc media is a bit expensive.
It looks like an excellent medium for data collections a tenth the size of 
what I'm playing with.



It seems that it is still necessary to maintain multiple copies 
(geographically separate - we had a 4.4 quake yesterday morning), on 
multiple different media, and make new copies on a regular basis.



--
Grumpy Ol' Fred ci...@xenosoft.com

Re: R: Large discs (Was: Spectre & Meltdown

[Sam O'nella via cctalk]

You're one of the first people I've heard quote that. Do you know where that is 
said? Years ago several friends and myself all picked up 64mb usb thumb drives 
so we could have multiple backups of a game and few other projects we were 
coding.  Maybe it was an extended period of time (we ended up switching to 
compatible removable drive bays) but 2 out of 3 of us lost all the data on our 
thumb drives around the same time. 
I haven't heard may others share the concern but i wouldn't use ssd as a tech 
unless im forced to for that reason.
 Original message From: Mazzini Alessandro via cctalk 
 Date: 1/5/18  7:15 AM  (GMT-06:00) 
I'm  not sure I would use SSD for long term "secure" storage, unless maybe
using enterprise level ones.
Consumer level SSD are, by specifics, guaranteed to retain data for 6 months
if unpowered... any more time means being lucky. Would suck to save, store,
and after some years find (over snipped)

R: Large discs (Was: Spectre & Meltdown

[Mazzini Alessandro via cctalk]

I'm  not sure I would use SSD for long term "secure" storage, unless maybe
using enterprise level ones.
Consumer level SSD are, by specifics, guaranteed to retain data for 6 months
if unpowered... any more time means being lucky. Would suck to save, store,
and after some years find the data mangled...

-Messaggio originale-
Da: cctalk [mailto:cctalk-boun...@classiccmp.org] Per conto di Fred Cisin
via cctalk
Inviato: venerdì 5 gennaio 2018 03:38
A: General Discussion: On-Topic and Off-Topic Posts
Oggetto: Large discs (Was: Spectre & Meltdown

On Thu, 4 Jan 2018, TeoZ wrote:
> Hard drives NEVER keep up. Bragging about how many DVD's (90's 
> technology) you can store on current HD means little to people who 
> have ultra HD Blueray videos that take up to 100GB of space. Heck even 
> a single game download can be 50GB these days.

I'd be interested in hearing about opinions of the 100GB "M-disc".  I've
heard that they have decent longevity, and, the "low" capacity ones are
interchangeable with conventional DVDs.

I can still put 20 100GB DVDs (2017 technology) on a 2TB 2.5" Thin SATA.
However, I'm also looking for multi-terabyte storage.
Are higher capacity DVDs on their way?
Howzbout multi-TearByte SSDs?


> And I wouldn't mind one of those old networked DVD changers (I think 
> Sony sold them commercially) to play around with.

I still want one of the ones that Kieth Hensen designed. Converting it from
CD to DVD would be completely TRIVIAL (finding DVD drives with suitable form
factors and loading options)

--
Grumpy Ol' Fred ci...@xenosoft.com




> I always wanted Keith Hensen's "Kubik"? CD changer.  Big "carousel 
> slide tray" full of 240?! CDs/DVDs, in a square box, with a drive in 
> each corner.  The drives were SCSI, and the load/unload/select control 
> was RS232. The big square boxes could be stacked, for a larger 
> collection, and there was a trivial mod to make the tray removable, so 
> that the top box could be swapped with as many trays as you had shelf
space for.
>
> 'course hard drives caught up, and I now have about a thousand DVDs in 
> MP4s on a shirt pocket HDD.  (including ALL of the Doctor Who's that 
> were released on DVD, Red Dwarf 1 - XII, Dark Matter, Torchwood, 
> Twilight Zone, Prisoner, Marx Brothers, Doc Martin, One Foot In The 
> Grave, etc.) The DVD images (V .MP4) take over 5TB.