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Comment by cluda01 | Hacker News Reader

Do flash drives still have a ceiling for how many times you can re-write a particular cell? This is fairly common lore and the article didn't mention it.

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The following link has information about the life-span of SSD's:

http://www.tomshardware.com/reviews/ssd-520-sandforce-review...

Briefly, under heavy use, a drive can last at least five (5) years.

Edit: Corrected a typo.

Yes, my understanding is that this is inherent in the technology.

AnandTech had a pretty good article about it a few months ago. I'm sure there are others as well.

http://www.anandtech.com/show/5518/a-look-at-enterprise-perf...

Yes, but there are two types of flash cell you can use. SLC cells have an order of magnitude higher write-cycle lifetime than MLC cells, which is why there's a difference in "enterprise" vs. consumer ssds. In practice for most uses an SLC based flash drive will be retired before it reaches its durability limits.

Eh, I just had an X-25M G2 start to fail the other day, after two years of desktop use. Intel replaced it within the week for free, but it was hardly retired.

Just a question, did you take the swap partition off the SSD? That's one of the main tips I've seen in improving SSD life-spans.

I didn't, but I don't know if it was swapping all that much... Maybe that was it.

The x-25m uses MLC flash cells. All other things being equal you'd expect an SLC based SSD to have a 10x longer lifetime. Also, can you confirm that your device failed due to write cycle exhaustion or could it have been due to a firmware bug instead?

Oh, sorry, I didn't realize you were talking about SLC. Yes, that's true. It was cycle exhaustion, as bad sectors started appearing and SMART reported a high end-to-end error count. I had the latest firmware, nothing helped.

Failure rates for flash drives seem to be driven by controller problems or bugs more than actually wearing out the flash. In order to avoid wearing out the flash they implemented very sophisticated software in the controller, and those controllers get wedged as a result (ironically.)

What do you mean by "wedged"?

Never actually delete any data, and you don't have to worry about re-writes.

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