Intel SSD 730 (480GB) Review: Bringing Enterprise to the Consumers

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• futrtrubl - Friday, February 28, 2014 - link

  "JEDEC's SSD spec, however, requires that client SSDs must have a data retention time of one year minimum whereas enterprise drives must be rated at only three months"
  I hadn't actually thought about this before for SSDs and after doing some checking around this seems to be the minimum retention time once the endurance cycles have been exhausted.
  Presumable this retention time is higher for sectors that are not exhausted. Does anyone know what sort of retention times could be expected from fresh/moderately used drives?
  The next question would be do controllers move once written data around to refresh this data and/or as part of wear leveling (like OS files that are untouched after the install)?

• Mr Perfect - Friday, February 28, 2014 - link

  I don't know about your first question, but the answer is "yes" to your second question about the wear leveling. Controllers try to keep writes even across all blocks to keep endurance up.

• futrtrubl - Saturday, March 1, 2014 - link

  Sorry, that was a badly worded question but yes I am aware that wear leveling exists. What I am asking is, if you write a file once and then only read from it for the next few years while the rest of the drive is being written/rewritten, will the controller intentionally rewrite or move that file? Whether it does it for wear leveling or to refresh "old" data is less important but would be nice to know, if it does.

• Solid State Brain - Tuesday, March 4, 2014 - link

  SSD-spec NAND memory is supposed to have a 10 years data retention when fresh (0 write cycles). I haven't been able to find much real world data about it, but from a Samsung datasheet about their enterprise drives, inclusing those with TLC NAND memory (here http://www.samsung.com/global/business/semiconduct... ) one can extrapolate that for the rated endurance with sequential workloads at 3 months of data retention, TLC NAND cells would have to endure about 2000 write cycles.
  So very roughly, assuming it's the exact same memory of the consumer drives (no reasons to assume it's not the case) for these drives we have: 0 write cycles = 10 years retention, 1000 cycles = 1 year retention, 2000 cycles = 3 months retention. Torture tests by users worldwide have shown that at over 3000 write cycles, these drives have a data retention ranging from hours to days. So, we could further summarize this as:
  
  cycles / data retention days
  0000 3650
  1000 365
  2000 36.5
  3000 3.65
  
  If you plot these values you can see that there's an inverse exponential correlation between NAND wear and data retention.

• Solid State Brain - Tuesday, March 4, 2014 - link

  It turns out I realized too late before clicking "reply" that for the 2000 cycles datapoint I used about one month of time instead of 3 months. It should be 90. It doesn't affect the end point I was making, though.

• SiennaPhelpsigi - Saturday, March 1, 2014 - link

  Parker . I can see what your saying... Margaret `s bl0g is impressive, last thursday I bought a great Porsche 911 from having made $8447 this past month an would you believe 10 grand this past month . this is certainly the most-comfortable job I've ever had . I began this nine months/ago and pretty much immediately began to bring home over $77, per-hour . Learn More W­ o­ r­ k­ s­ 7­ 7­

• kmmatney - Saturday, March 1, 2014 - link

  You can make that kind of money, in real life, as an engineer. Why is their a shortage of engineers in the U.S.again?

• Jflachs - Saturday, March 1, 2014 - link

  So um, the 840 Pro is still the best SSD then, right?

• emn13 - Sunday, March 2, 2014 - link

  None of samsungs drives have any form of power loss protection, so unless you really need that last bit of performance, I'd avoid them, especially since there are cheaper drives that do have that protection.
  
  If you really do need top-of-the line performance, well, then your choice becomes considerably harder.

• amddude10 - Friday, November 28, 2014 - link

  Power-loss protection isn't very important in a laptop or if someone has a good UPS on a desktop, or at least that's what I would think, so in those cases, samsungs look very good indeed.