Re: SSD TBW

On 8/21/2026 4:01 PM, Computer Nerd Kev wrote:
> In comp.misc Don Y <[email protected]> wrote:
>> On 8/21/2026 12:32 PM, Scott Dorsey wrote:
>>>    =?UTF-8?B?IEdsb3N0w6lpcg==?=  <[email protected]> wrote:
>>>>
>>>> I do not yet have a first-hand experience of an SSD failure. Don Y
>>>> complains in news:sci.electronics.design that an SSD suddenly
>>>> completely failed, instead of gradual partial degradations of a hard
>>>> disk. What does Lawrence D'Oliveiro mean by
>>>> "before
>>>> showing signs of failure."?
>>>
>>> With a conventional hard drive, first you might see some error numbers
>>> creeping up on your SMART tool, as individual blocks start failing.  There
>>> is a bad block replacement process that is transparent to the OS so all you
>>> see are bad numbers on SMART.  Then you start getting media errors and
>>> then it's all over.
>>
>> The firmware in spinning rust controllers has matured over decades.
>> This is not the case with SSDs (especially early entrants to the market).
>>
>> Note that the media fails in different ways and the controller has
>> to understand these and adequately address them, in the wild.
> 
> The non-standard SSD card in my EeePC 701 was repeatedly getting
> corrupted data, a common problem with these I believe. So I

I had an EeePC with *two* "drives" -- a tiny one and a slightly larger one.
I set the tiny one to boot a BSD kernel which then mounted the rest of
the filesystem (e.g., /usr) that resided on the "larger" one.

For a while, I used this to DL the most recent "distfiles" archive
(see pkgsrc) as I could attach an external magnetic disk and then
note the differences (additions) present on the public web site vs.
what I had accumulated to date.  And, store the EeePC in a desk drawer!

[Often, older sources would disappear so rsync(1) was a bad choice]

But, the small size and the fact that it had a built-in TINY
display and keyboard eventually grew tiresome.  So, I replaced
it with a full-size laptop -- where I could install a larger
magnetic disk and not be bothered with mounting the (necessary!)
filesystem present on the secondary drive.  Now it resides on a shelf
in the closet instead of inside the desk...

> repartitioned it using just the upper half of the drive instead of
> all the space for the system partition, and no more corruption.
> Obviously the wear leveling done by that SSD controller isn't very
> sophisticated and had worn out the flash used for the starting

I think EeePCs aren't intended for much more than email, etc.
And, running a UNIX on it (BSD in my case) still does writes to
the / partition (think /var/log).  Perhaps retooling the system
might cut down on that (mount /var as a tmpfs?)

I presently use small (16G) thumb drives as the "boot disk" in
several of my appliances -- so I can keep the drive bays free
and "pure" for regular media.  I've not had any problems, yet,
but have played the tmpfs trick to reduce the risk.

> sectors of the drive. I thought modern SSDs for use in PCs must
> have improved from that to some extent. But it's a case of gradual
> failure more like a HDD (though I've certainly seen sudden death
> with HDDs too).

HDDs tend to either have a problem spinning up or a problem with
the head actuator assembly, when they "die dramatically".
Before that time, they just accrete bad sectors on the GDL.

[I've not explored whether this can be "reset" like on a SCSI
drive -- though suspect that would be A Bad Idea]

>> Many "Thumb drives" have had problematic firmware (some Phison and
>> Hynix controllers).  The fix requires a firmware upgrade -- WHILE
>> the drive is still willing to talk to its host.
> 
> I didn't realise firmware upgrades were available for USB drives.
> Is there any way to apply them from Linux?

Dunno as I don't run Linux.  Maybe start here:
    <https://www.usbdev.ru/files/smi/smimptool/>

I rescue "recovery media" for Windows machines (typically 8GB
thumb drives that have been factory marked as R/O).  These
tools let me convert them to usable 8G drives -- a nice size
to emulate a DVD-DL.  Especially as optical drives are becoming
scarce in machines (or, physically incompatible with the sizes
of those machines -- e.g., NUCs)