Re: Spare SSD anybody?

[Alexander Kobel]

On 2016-06-01 11:07, David Kastrup wrote:
> David Kastrup <address@hidden> writes:
>
> > Hi,
> >
> > my current development SSD, graciously donated by James, currently has
> > the following readings:
> >
> > Vendor Specific SMART Attributes with Thresholds:
> > ID# ATTRIBUTE_NAME          FLAG     VALUE WORST THRESH TYPE      UPDATED  
> > WHEN_FAILED RAW_VALUE
> >    5 Reallocated_Sector_Ct   0x0033   099   099   ---    Pre-fail  Always       
> > -       13
> >    9 Power_On_Hours          0x0032   094   094   ---    Old_age   Always       
> > -       25748
>
> Ok, I might have been panicking because of all the lines with "Pre-fail"
> and "Old_age" but they only indicate the _category_ of the respective
> settings.  Sorry for that.
>
> I'm still trying to figure out the readings as such though.  The
> "documentation" including online is not much help.

Hi David,

recently I was afraid about my SSD for the same reason, so I asked our 
institute's IT service staff who cares for some dozens (hundreds?) of 
laptops and desktops with SSDs.

They say that even power users of hibernation with high rate of data 
turnover didn't manage to damage their SSDs lately; the horror stories 
for the first generations of SSDs seem not to apply anymore. You still 
have to take a bit of care (try to have some empty space, and run fstrim 
once in a while), but other than that you should be fine.
As you experienced, the SMART information is rather unhelpful unless you 
have additional context by the manufacturer; more often than not, the 
only semi-reliable source are the manufacturer's own toolkits (which, 
unfortunately, are hardly available on Linux).

However, there have been a few reports in the past about shaky power 
supply for the disks, probably when laptop batteries grow older. Some 
SSDs cope with that without problems, others are very sensitive to 
voltage differences (?) and suddenly become unstable. Signs of this 
behavior are ATA warning messages concerning the "ATA interface" in 
dmesg output, such as those:
  https://lime-technology.com/wiki/index.php/The_Analysis_of_Drive_Issues
Quote: "There have been too many cases of drives thrown out or returned 
by an RMA process, when the problem was just a bad cable!" - which 
exactly matches the experience of our IT.
If drives barf out for those reason, they have always been able to copy 
the contents with an external adapter - annoying, but not dangerous.


That being said: which form factor/connector do you need? I can ask if I 
can grab something. Many parts from few-year old machines are sorted out 
regularly here. Not sure about hard disks, though - there might be 
regulations for data protection that prevent them from giving out old 
drives.


Cheers,
Alexander