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Samsung Acknowledges and Fixes Bug On 840 EVO SSDs
Lucas123 writes: Samsung has issued a firmware fix for a bug on its popular 840 EVO triple-level cell SSD. The bug apparently slows read performance tremendously for any data more than a month old that has not been moved around on the NAND. Samsung said in a statement that the read problems occurred on its 2.5-in 840 EVO SSDs and 840 EVO mSATA drives because of an error in the flash management software algorithm. Some users on technical blog sites, such as Overclock.net, say the problem extends beyond the EVO line. They also questioned whether the firmware upgrade was a true fix or if it just covers up the bug by moving data around the SSD.
This is almost certainly a firmware bug with their read disturb compensation. At least they're owning up to it - but wow.
I'd rather go with stable than EXTREME, so I go with Intel. It might not be the fastest around, but we rarely hear about Intel SSD problems.
Available soon below my post, someone with a story about failed Intel SSDs.
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"Dos version for MAC, Linux users ... Will be released on end of Oct."
http://www.samsung.com/global/business/semiconductor/samsungssd/downloads.html?CID=AFL-hq-mul-0813-11000279/
Let me guess - the source for that firmware patch is stored on a Samsung EVO 840 disk?
More technical detail as to what is going on.
http://www.anandtech.com/show/...
Couldn't write a proper wear levelling algorithm if their life depended on it.
First the MAG4FA/KYL00M/VYL00M data corruption bug that affected the Galaxy Nexus - https://android.googlesource.c...
Then (actually BEFORE it, Google found it during Galaxy Nexus development but Samsung kept it hush-hush - but it became a public issue much later) - the infamous Samsung Superbrick fiasco (If you fired a secure erase command at the chip, it had a chance of permanently corrupting the wear leveller data to the point where the chip's onboard controller would crash until you power cycled it any time you accessed that region of flash). - https://git.kernel.org/cgit/li...
Then pre-release 840 PRO devices suffer from the SAME DAMN BUG SAMSUNG HAD BEEN AWARE OF FOR OVER A YEAR - http://www.anandtech.com/show/... - While this only affected review devices, the fact that this was a known bug since before the release of the Galaxy Nexus (a year earlier) is inexcusable.
Then there was the Galaxy S3 "Sudden Death Syndrome" issue in late 2013... - https://github.com/omnirom/and...
Then there were a few other issues - http://wiki.cyanogenmod.org/w/...
Now this...
retrorocket.o not found, launch anyway?
For SATA SSDs, there's no more extreme. All modern SSDs saturate a SATA-3 bus. If you wonder why they all benchmark at 540MB/sec reads and writes, that's why - SATA is the bottleneck, not the SSD.
PCIe SSDs are where the "extreme" ones go, and even the most conservative ones are pretty damn fast - the old MacBook Air's SSD clocks in at 750MB/sec read and write. I think the newer ones can hit 1GB/'sec now easy.
As for what to buy, well, Samsung, Intel and Toshiba are the general safe bets. Even with this bug, Samsung is still stable, just slow.
Intel's got a history of failure as well, but they seem to have gotten beyond it, and while they're not stunners, they generally are solid.
Toshiba's on the slower end of the scale, but Apple uses them, so they can't be TOO bad.
And yes, I say Apple, but you can see what Dell uses as well. The big OEMs that ship lots of units will generally pick ones that give the least warranty and support issues and thus are more conservative. Plus, recalls are expensive.
If you want to follow someone - pick Apple. Given the way news coverage is, if there's a problem with someone somewhere and their SSD in their Apple product, the whole world would know in a nanosecond. Someone as heavily scrutitinized as Apple (where even one failure in millions of computers sold would probably bring about SSD-gate) means if there is a real problem, you'd already know.
SSDs will saturate SATA-3 for sequential reads and writes. My Crucial M550 gets 500MB/s vs 150MB/s on my Western Digital. Over a 3 fold improvement!
However where SSDs really shine is random reads and writes. This is why SSD's make PC's more responsive. My Crucial gets 26MB/s vs. 0.66MB/s on the WD. Almost 40 fold improvement, but not near saturating SATA-3. So there is still improvements to be made on random read/write performance.
More and more I see PC's slowing to a grind, and it's due to the Hard drive thrashing crazily at less than 1MB/s! Put an SSD in (any SSD) and it speeds right up.