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2nd 840 Evo Fix Is Here
The fix refreshes old data on a regular basis. This proves that it's not a software issue, it's an issue from Samsung's TLC NAND.

That is really UNFORTUNATE!!!!!!

This cannot be good.
I wonder how many other SSD/Nands are out there that we know nothing about. I cannot imagine that samsung is the only brand that has this issue. There has to be some underlining issue which was exposed. Samsung was a very popular brand and known for its blistering speeds. It would be naive to think this issue is isolate, that it doesnt exist anywhere. It maybe that the issue manifest itself in evo840 more quickly or that people have yet to stumble on this issue with other brands for whatever reason.

this is really really interesting
Yes, it is interesting. The thought had occurred to me when I read the article that it's an issue with TLC in general. I wonder if that's true, and how many TLC-based SSDs are suffering the same issue.
I propose that Samsung 840 had degrades at a quicker rate or that people just haven't bothered checking budget and non performance drives.

This is something we really need a site to check into.

This is really not a good thing. But it looks a like Samsung will already have a work around.
As for the data rewrites effecting the life span, if it is moving the data it absolutely will. But I would think they could just recharge the data without moving it, which means it wouldn't be changing states.
Now it turns out the fix is out, but it requires firmware that isn't out yet. F*** Samsung.
Quote:PC Perspective notes that several other sites have mirrored the software already, and that those downloads are identical to the one provided by Samsung. There's another catch, though. The "Advanced Performance Optimization" tool designed to restore old data to full speed requires updated firmware that doesn't seem to be available. Samsung's download page only lists old firmware revisions, and the Magician software's built-in updater has nothing for the drives I've got in the lab. PC Perspective suggests Samsung's firmware server may be swamped at the moment. Restarting the Magician software is supposed to help, but it hasn't worked for me yet.

The updated firmware should have the periodic refresh feature designed to prevent further slowdowns in active systems. That mechanism can't prevent performance degradation on unpowered drives, but it's unclear how long it takes the problem to manifest. I'm still waiting for Samsung to clarify a few details about the refresh routine, including how frequently data is rewritten.

Given the window for the download limit, a wider release seems to be planned for the 27th or 28th. Samsung may be rolling out the new fix slowly to ensure there are no problems with the first wave of updates. That's not a bad idea given the drive's popularity—and the fact that this is the company's second attempt at a fix.
Digistor has come to the conclusion that I suspected, that this is an issue with TLC NAND.
Quote:What does this all boil down to?
Simply that TLC NAND is not the future of data storage, and it doesn’t even have a good seating in the present. If your data matters in the long term, you’ll want to go with a higher-quality NAND: MLC-NAND for your basic SSD needs, or SLC-NAND for industrial use or super-sensitive data storage. There’s no other way about it.

It is a shame that samsung is catching all the flack. This is a much bigger than them
Are you kidding?  Samsung gets a free pass, and TLC's failure to penetrate is scapegoated on another controller:
Quote:The SSD industry has been talking about TLC NAND for over three years now. We published our first post, Understanding TLC NAND, back in early 2012, but in three years we have actually seen very little TLC NAND making it to the SSD market. Samsung was an early adopter by introducing the SSD 840 in September 2012, but Samsung has always been a special case as its SSD business is fully vertically integrated. When you design and manufacture everything in-house, it's obvious that you will have a technological advantage when it comes to adopting new technologies.

TLC is tightly linked with both controller technology and NAND production because TLC inherently has a higher error rate, which needs a stronger controller (although admittedly Samsung has had some issues with TLC). The lack of proper controller is the reason why other NAND vendors haven't invested as heavily on TLC as Samsung because Micron, SanDisk and the like have to rely on whatever third party controllers are available on the market. Without a high volume product to put your TLC NAND into, it means that there's no reason to produce TLC in a large scale, which defeats the cost savings that TLC bring. Micron tried to promote its 25nm TLC NAND for a while a few years ago, but it quickly realized that the available SSD controllers aren't capable of creating a reliable product -- at least not one that would bring any cost savings since the drive would need serious over-provisioning for endurance and ECC parity.

Due to the lack of controller support, nobody other than Samsung and SanDisk have a TLC SSD on the market, although SanDisk had to rely on heavy over-provisioning with 5:1 parity ratio since the Marvell controller used in the Ultra II wasn't designed with TLC in mind. Silicon Motion's SM2256 will be the first commercially available controller and firmware combo with TLC support and today we are taking an early look of the platform in the form of a reference design sample. ADATA already announced its SP550 SSD that will be based on the new SM2256 controller and available later in the summer, but given how many OEMs rely on Silicon Motion's controllers nowadays we will likely see a large number of SM2256 based TLC drives entering the market by the end of the year.

Of course, they have to throw in a brief caveat at the end:
Quote:In any case, it will all boil down to pricing anyway. If Silicon Motion's OEM partners can drive the prices down with the SM2256, I will be totally fine with the performance because the SM2256 is still more than fine for basic usage. TLC SSD pricing was actually one of the things I was very vocal about at Computex because OEMs can't price their TLC drives similarly to the MLC ones and expect it to be a good sale. TLC isn't as good as MLC and that's a fact that nobody can deny. Especially after Samsung's issues with TLC the market has become more skeptical about TLC in general, so saving a few bucks isn't enough anymore for the educated buyers to choose TLC over MLC -- I think the difference has to be in the order of 10% or so to be worth the lower performance and possible long-term reliability risks that TLC brings. I do believe that the SM2256 is a vehicle capable of delivering such cost savings, but for now we will just need to wait and see what happens.

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