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Power-Loss-Protected SSDs Tested: Only Intel S3500 Passes
lkcl writes "After the reports on SSD reliability and after experiencing a costly 50% failure rate on over 200 remote-deployed OCZ Vertex SSDs, a degree of paranoia set in where I work. I was asked to carry out SSD analysis with some very specific criteria: budget below £100, size greater than 16Gbytes and Power-loss protection mandatory. This was almost an impossible task: after months of searching the shortlist was very short indeed. There was only one drive that survived the torturing: the Intel S3500. After more than 6,500 power-cycles over several days of heavy sustained random writes, not a single byte of data was lost. Crucial M4: failed. Toshiba THNSNH060GCS: failed. Innodisk 3MP SATA Slim: failed. OCZ: failed hard. Only the end-of-lifed Intel 320 and its newer replacement, the S3500, survived unscathed. The conclusion: if you care about data even when power could be unreliable, only buy Intel SSDs."
Relatedly, don't expect SSDs to become cheaper than HDDs any time soon.
"after experiencing a costly 50% failure rate on over 200 remote-deployed OCZ Vertex SSDs"
Stop gloating about how you got the good batch of OCZ SSDs! Some of us weren't so lucky....
AntiFA: An abbreviation for Anti First Amendment.
and get a UPS. Why blow more money on a slightly more reliable SSD when a UPS is so much cheaper?
These things are already expensive; surely spending a few more cents per unit on a capacitor to ensure power loss reliability isn't a big deal.
The cap only has to be big enough so the controller can do a controlled shutdown.
Slightly more seriously than my last post, the S3500 was the only enterprise-grade SSD tested in that batch. Frankly, I have little sympathy for you if you expected consumer-grade SSDs to perform like Enterprise-grade SSDs in a mission-critical application.
Consumer grade drives, even/especially the "high performance" ones that will often benchmark better than the "overpriced" enterprise drives, ain't designed to have perfect data retention. Of course, consumer or enterprise, any drive can fail and appropriate measures including RAID and backup* should always be in place no matter what type of drive you have.
* Yes, RAID != backup, I know, don't bother making that post.
AntiFA: An abbreviation for Anti First Amendment.
Does this mean the write-cache is NAND too? I do not see that in the features for the SSDs they selected.
Also, why was Samsung excluded? Their 800 series with RAID support has been tested in the past with long term writes with great results.
http://us.hardware.info/reviews/4178/10/hardwareinfo-tests-lifespan-of-samsung-ssd-840-250gb-tlc-ssd-updated-with-final-conclusion-final-update-20-6-2013
I do not mean to plug a particular brand, but the range of SSD's tested in the articles does not seem very expansive nor do they seem to fit into the criteria they specify.
There's still one 720RPM laptop drive, I just bought a 1TB 7200RPM HGST drive recently...
That said one of the newer Seagate drives scored faster in a speed check. Not sure what to make of that.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
People who have "important data" and fail to make a backup copy - no matter which type of media they are using - deserve to lose their data. Seriously, what you said doesn't only apply to SSD's.
Seven puppies were harmed during the making of this post.
Steve Jobs created UPS technology?
You're missing the point of this advertisement. Only an Enterprise class Intel drive will save your data. All other factors of the test are irrelevant, like the other drives being consumer grade or that all the other drives were beaten with a rubber mallet for 5 minutes before each test while the intel was handled with silk mittens attached to 7 grounding point. And you definitely don't need to pay attention to the fact the power loss with the Intel drive was carried out via software shutdown while the other drives were done by power surging the computer until the motherboards burst into flames.
Nope, pay no attention to that irrelevant information. Just remember that only official certified and authorized Intel drives can protect your data. Now please wait while the next advertisement queues up, which will explain how the Intel drives protext your data with a computer rendering of the drive tucking your data into bed at night before turning off the lights.
I don't suffer from insanity, I enjoy every minute of it!
Correct me if I'm wrong, but from my skim through the article, it seems like he only used a single drive of each type. That makes it hard to demonstrate that the differences he saw were real, and not just random. I.e., it may be that all drives have a 75% chance of surviving the test, and that the Intel one just happened to be the lucky one. A more robust test would be to test N copies of each drive. N = 5 should give pretty good significance if this really is completely deterministic.
HDDs, even the cheapest ones nowadays, allow the software to enforce the order in which pending data is written to safe permanent storage and software to known that pending data has indeed been safely committed to permanent storage.
The operative systems, file systems and applications build upon this to ensure that, in case of an unexpected crash, you don't end up with a corrupted file system or data. You may lose files created in the last 5 minutes, but you won't end up with a file system so corrupted that you need to re-install your computer.
Databases uses this to ensure that, once you've clicked "pay" in a e-commerce site, it will either record it properly or not at all, so you don't end up with half-way situations where you get charged and don't get the product you paid for or vice-versa.
According to reports like TFA and the article TFA was attempting to reproduce, a lot of cheap SSDs break this guarantees.
Technically -yes-, but the issue can be catastrophic with an SSD where as with an HDD, you just loose maybe a file. Both the drive and a journaling filesystem should be able to recover from. With an SSD however, the LBAs are not mapped predominately to memory cells. They get reassigned based on whatever algorithm of wear leaving is employed. If this separate abstracted database to the drive's firmware itself becomes corrupted, you could lose the entire drive. And that's the problem, yet another abstraction that SSDs use that's completely vulnerable to uncommitted writes-backs from power failure. This is something where the OS and filesystem can't help you on an SSD. Unfortunately.
Life is not for the lazy.