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Endurance Experiment Kills Six SSDs Over 18 Months, 2.4 Petabytes
crookedvulture writes Slashdot has previously covered The Tech Report's SSD Endurance Experiment, and the final chapter in that series has now been published. The site spent the last 18 months writing data to six consumer-grade SSDs to see how much it would take to burn their flash. All the drives absorbed hundreds of terabytes without issue, far exceeding the needs of typical PC users. The first one failed after 700TB, while the last survived an astounding 2.4 petabytes. Performance was reasonably consistent throughout the experiment, but failure behavior wasn't. Four of the six provided warning messages before their eventual deaths, but two expired unexpectedly. A couple also suffered uncorrectable errors that could compromise data integrity. They all ended up in a bricked, lifeless state. While the sample size isn't large enough to draw definitive conclusions about specific makes or models, the results suggest the NAND in modern SSDs has more than enough endurance for consumers. They also demonstrate that very ordinary drives can be capable of writing mind-boggling amounts of data.
The fact that 2 of them died without warning is disappointing. I would rather have a shorter life time, but a clear indication that the drive is going to die.
Being an AC, I would chalk this up to a joke or trolling. But.... on the off chance that you are serious, I will bite.
Yes, you COULD use an SSD as swap, but it will not help THAT much. An SSD is much faster than a mechanical disk, but still a couple of orders of magnitude slower than real RAM. That upgrade would be like the difference between jogging with 50 pounds on your back, and then lowering it to 35 pounds. Yes, it will make a difference and make things better, but how much better to have no weight at all?
Just get more RAM. If your system cannot hold more RAM, then get a new mobo. If you regularly go over 16 GB of actual RAM in use, even going to a slower processor will be an improvement if you stop swapping. Hitting the swap file is a great way to make a fast processor do nothing for a while.
"-1 Troll" is the apparently the same as "-1 I disagree with you."
Talk about your planned obsolescence - not a single sector reallocation registered, but the firmware counter says it's write-tolerance is reached so it kills itself. I suppose it's nice that it switches to read-only mode when it dies, except for the fact that it bricks itself entirely after a power cycle. I mean come on - if it's my OS and/or paging drive then switching to read-only mode is going to kill the OS almost immediately, and there goes my one chance at data recovery. Why not just leave it in permanent read-only mode instead? Sure it's useless for most applications, but at least I can recover my data at my leisure.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Who thought this was a good idea? If the drive thinks future writes are unstable, good for it to go into read only mode. But to then commit suicide on the next reboot? What if I want to take one final backup, and I lose power?
As SSD cells wear, the problem is that they hold charge for less time. Starting new, the time that the charge will be held would be years, but as the SSD wears, the endurance of the held charge declines.
Consequently, continuous write tests will continue to report "all good" with a drive that is useless in practice, because while the continuous write will re-write a particular cell once every few hours, it might only hold a charge for a few days - meaning if you turned it off for even a day or so, you'd suffer serious data loss.
SSDs are amazing but you definitely can't carry conventional wisdom from HDDs over.
I have no problem with your religion until you decide it's reason to deprive others of the truth.
OCZ? Well there's your problem.
I'm actually not convinced it's a terrible idea. It seems to me that when swapping really gets slow, its because of thrashing the hard disk. SSD may be several orders of magnitude slower than memory, but it's also several orders of magnitude faster than a thrashing HDD. It seems like it might be a reasonable tradeoff to make. New memory might require a new motherboard (and maybe a new processor), costing several hundred dollars, a not-insignificant amount of effort to swap it out, possibilities of new bugs with hardware incompatabilities, etc...all for some additional memory with, 99% of the, probably serves no additional benefit. On the other hand, it takes no more than a few minutes to move your swap between drives, costs nothing, and has almost no risk of any incompatibilities (unless you start ending up with applications fighting for throughput under the additional load).
If all programs and operating systems were perfect, increasing RAM would help more than faster swap. But things aren't perfect and operating systems like to talk to swap 'just because'.
On my aging Mac Pro with 32 GB RAM I put a 60 GB SSS (left over from a laptop upgrade) in as swap. Seems to make a modest difference with Premiere, After Effects and Vue, especially renders. But it really isn't all that noticeable. Not as noticeable as increasing the RAM. But if you have an extra drive caddy and an extra SSD it's easy to try.
Faster! Faster! Faster would be better!
I haven't gone back to hard drives since I tried an IBM Deskstar. Windows 7 makes for a lot of floppy-swapping, but at least my data is safe.
How can I believe you when you tell me what I don't want to hear?
I've owned Tivos since 2002 and I've only had one blow a drive, a series 3 I bought from WeakKnees with an upgraded disk in it. The drive didn't fail spectacularly or even completely, we just had a ton of playback problems and recordings that grew increasingly unreliable. That Tivo was bought in 2007 and the drive was replaced last fall.
The original Tivo I bought in 2002 finally got tossed without a drive failure when Comcast gave up on analog SD channels a couple of years ago. I think this was after broadcast went digital, making it useless. I had ideas of adding one of those boxes for people with analog-only TVs, but I wasn't sure if the IR emitter would work with the digital TV converter and it was kind of silly to jump through those hoops to record HD as SD only to watch it on an HD TV.
The other two Series 3s have original drives and work fine.
SATA revision 3.0 = 6 Gbit/s
DDR3 - 1600 = 12800 MB/s
"MB" = Mega-BYTES, so multiply by 8 for bits/seconds
DDR3 - 1600 = 102400 Mbits/s
DDR3 - 1600 = 102.400 Gbits/s
So, the peak bandwidth is about 17 times faster!
Now, let's look at latency.
Typical DDR RAM latency is around 10 ns (give or take, but that is an average number)
Typical SSD latency is around 0.1 us, which is around 100 ns. About ten times more.
One more thing here about these numbers.... An SSD is **NOT** RAM. If you page, you have to get the data FROM the SSD and put it INTO your RAM. From there, the RAM must be read again. So, even IF your SSD were exactly the same speed as your RAM, it will still be slower because it must be copied into RAM first before it can be used.
As to whether it is unreasonable, that depends. It will not cost much to try, but still a rather bad idea if you do a LOT of swapping.
"-1 Troll" is the apparently the same as "-1 I disagree with you."
Hmm, wikipedia suggests that a typical SSD access time is actually about 10us, so about 1,000x slower than DDR RAM, not 10x
However, Typical HDD acces times are around 10ms, or about 1,000x slower still.
So while an SSD page file will be much slower than RAM, it will also be much faster than a HDD. Moreover, page file access patterns typically involve megabyte-sized bock writes and kilobyte sized (single page) random reads - which play directly to the strengths of a SSD.
Certainly more RAM will potentially grant a much larger performance boost to RAM-starved applications, but an SSD is far cheaper and should, in theory at least, offer a dramatic improvement over a HDD for page files. Plus it offers many other performance boosts as well, which may make it a much more attractive upgrade option for someone on a budget.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
On the whole, OCZ has a 10% RMA rate while the industrial average was about 0.5% and Intel and Samsung where about 0.25%. You must feel lucky.
Where did you get those numbers? I've worked for a manufacturer of computer retail products such as OCZ and knowing the market I know that 10% would have killed the business.
Funny you should mention that:
http://arstechnica.com/gadgets/2013/11/once-great-ssd-manufacturer-ocz-filing-for-bankruptcy/
This reminds me of the systems they tried to impose in the early 70s' US cars: if the seat belts weren't latched, the cars would not start. No, not just an annoying bong for a brief time; the freaking engine would not even turn over. And this being completely analog, system failures happened quite a bit. But fear not! If there was a failure, there was an under hood button you could push to bypass the system. Once. A one-time use, then you had to tow the car to a dealership for a new box. As most everyone by-passed this insanity, the system was quickly dropped.
Here's hoping Intel also comes to their senses about their one-time recovery window (hopefully with some well-deserved threats from the FTC).