[ale] OT SSD remaining lifetime indicator

[Ron Frazier (ALE)]

On 9/7/2012 4:32 PM, David Tomaschik wrote:
> On Thu, Sep 6, 2012 at 7:02 PM, Ron Frazier (ALE)
> <atllinuxenthinfo at techstarship.com>  wrote:
>    
>> Hi guys,
>>
>> I was doing research on SSD's and ran across this. It's an SSD remaining
>> lifetime indicator. It monitors your ssd's and indicates their health as a
>> percentage from 0 - 100%. It also gives an estimated end of life date which
>> continually updates based on your usage of the drive. It does all this by
>> monitoring the SMART data from the drive and the number of write cycles. I
>> don't know anything about it other than what's on the website, but it looks
>> pretty cool. Unfortunately for this group, it's a Windows program. However,
>> it might be possible to run it under Wine or find something that does the
>> same thing in Linux. According to the website, when the drive's life has
>> expired, it becomes a read only device, like a giant dvd rom. The data
>> SHOULD still be there and remain readable. How long it remains readable, I
>> have no idea.
>>
>> http://www.ssd-life.com/
>>
>> Sincerely,
>>
>> Ron
>>      
>
> It most likely won't work under wine as getting that data from the
> drive requires sending raw device commands (ioctls on Linux) and I
> don't think wine provides an emulation layer for this.  (It might, but
> the use cases would be pretty limited.)
>
> My understanding is that smartmontools (at least as of 5.40) supports
> SSD wear level indication.  Basically, the drive can report what % of
> its spare blocks are still available.  Read (and record) that over
> time, extrapolate, and there's your wear leveling limit.
>
> That being said, most SSDs that die don't die because they've hit
> their write cycle limit.  I've personally seen a couple die due to
> controller failures, and those drives *completely disappear* from the
> system.
>
> I operate as if my drive will fail any second.  I have an extensive
> set of backups, and that's how I plan to preserve my data, not by
> trying to guess when a drive will fail.  (Or be stolen.)
>
>
>    

Hi David,

I meant to reply to this earlier, but hadn't.  Some of what you said 
echos what I said in a later post.  The "completely disappear" 
phenomenon is a problem, according to my research, since data recovery 
can be very dicey.  You know the data is sitting there in the NAND 
chips, most likely, but it takes very special expertise to get it out.  
I think operating as if "my drive will fail any second" is a good idea.  
I've just never been able to achieve it for any period of time.  I 
currently have online backups for my data running every 6 hours.  
However, I like to have image backups in case I need to recover a whole 
system.  In the case of Windows, sometimes I don't have install discs.  
Even if I did, installing my system to the way it was 3 years ago is not 
a very good option.  Restoring and recovering from that state would 
probably take me a week.  I like to be able to restore it to what it was 
a month ago, at worst.  I should image each drive every month, but it's 
hard to find the time.  Each computer backup requires about 30 minutes 
of personal time on my part hooking up and setting up then undoing the 
backup hard drive.  Also, each backup takes the computer out of service 
for 5 hours or so.  At this moment, I need to backup all my systems.  I 
don't like to leave the backup device plugged in in case something 
happens to the computer, virus, electrical fault, etc., I don't want it 
to fry the backup as well.  For now, this is the best scheme I have though.

Sincerely,

Ron


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Ron Frazier
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