(TechReport) SSD Endurance Gets Interesting at 300TB

Subject: General Tech, Storage | November 26, 2013 - 03:46 AM |
Tagged: ssd, endurance

Update 11/26/2013 @ 11:20pm Allyn weighed in, particularly about the Samsung drives. One thing that he notes (as does Tech Report in the original article) is that Samsung might just be more severe in its reporting of errors. For instance, he believes that it is just about impossible for SSDs to write 300TB of data without ever seeing a flash read error. Regardless of what they report, each of these drives keep on ticking. It is "significantly beyond the expectations of a consumer (non-Prosumer) SSD".

The Tech Report has been testing a batch of SSDs for their life expectancy over several months now. Results have been fairly interesting: drives were relatively stable even up to 200TB of cumulative writes; some drives even got faster. Now they have passed the 300TB threshold and we are seeing certain drives hit some harsh realities. As Scott Wasson said in a tweet:

 

 

In all, though, even the TLC offerings have surpassed reasonable expectations. Consumer drives are designed for consumer machines and will likely take decades to reach the hundreds-of-terabytes order of magnitude for today's usage.

View Full Size

Image Credit: The Tech Report

It makes me wonder exactly how over-provisioned enterprise hardware is if these, consumer, parts have such high reliability.

Source: Tech Report
November 26, 2013 | 03:58 AM - Posted by Branthog

Amusing that the most popularly recommended drive for performance and reliability among tech pundits and sites is faring the worst. While others are soaring beyond their suggested limitations and warranties, the Samsung seems to have gone a little beyond theirs and crapped itself.

November 26, 2013 | 11:57 AM - Posted by Allyn Malventano

There are many variables here, and I'd venture a strong guess that Samsung is more forthcoming in how their drive reports sector reallocations vs. the other controller types. The only difference is it's reporting sector reallocations. Intel also tends to be a bit more forthcoming about how their drives report sector issues - I've had brand new samples come with a few sector reallocations reported in the SMART data.

I'm highly suspicious of how the other drive firmwares are reporting. It should be statistically impossible for 300TB to be written and a controller *never* see a flash read error. This doesn't mean you don't get your data, it means the drive has to use ECC to correct the error.

The way Samsung reports their data may be mothing more than them being more conservative on what counts as a reallocation and how safe the firmware responds to errors seen.

After 300 TB written, the Samsung drive is still performing the same as the other units. They did note an actual read error on one of the tests, but that was with 300TB written to the drive. Given that it has likely done 1500 full flash cycles already, you have to realize that it would take a full 5 years to do the equivalent while writing over 160GB to the 250GB drive, each and every day. If you take into account the 840 (non-Pro) has a 3-year warranty, 300TB equates to writing 270GB each day - to a 250GB drive. That's right, you'd have to write more than one full drive volume, every day, for 3 years to reach 300TB written. That is significantly beyond the expectations of a consumer (non-Prosumer) SSD.

November 26, 2013 | 07:45 PM - Posted by Anonymous (not verified)

Agreed.

I would hands down trust a current model Samsung SSD over a mechanical drive any day.

November 27, 2013 | 12:49 AM - Posted by Pholostan

Yeah, it is very interesting. Will the drives that report zero reallocated sectors continue to say everything is fine and dandy right up to the moment they go belly up?

November 26, 2013 | 08:30 AM - Posted by Prodeous

With regards to Samsung. One has to remember that the 840 uses a Triple Level Cells (TLC 3 bit/cell) while others use MLC (2 bit/cell) or SLC (1 bit/cell)

They can store more data, and even with their rated 3000 write cycle? (please someone correct me on this) with their internal algorithm, are able to get to around 100 Terabytes of writes without any issues. And only after than it uses it's extra chips, allowing the drive to reach 300TB and still going.

For a regular consumer, at the price the 840 is offered (non pro) this is far more then enough.

Hopefully Allen can provide more feedback on Tech Reports findings?

Post new comment

The content of this field is kept private and will not be shown publicly.
  • Lines and paragraphs break automatically.
  • Allowed HTML tags: <a> <em> <strong> <cite> <code> <ul> <ol> <li> <dl> <dt> <dd> <blockquote><p><br>
  • Web page addresses and e-mail addresses turn into links automatically.

More information about formatting options

By submitting this form, you accept the Mollom privacy policy.