SSD Write Endurance 25nm Vs 34nm

[johnw]

Get the Intel 320 if you need most mature and reliable ssd because it has good endurance as shown here and also reliable controller with power capacitors etc.

I'm actually a bit down on Intel and the 320 SSD recently. A bug has shown up in the Intel 320 SSDs. It is somewhat random, but seems to be related to power-cycling, perhaps unsafe power cycles, perhaps sleep or hibernation. As far as I can tell, on any given power cycle the bug is unlikely to appear (at least I haven't had it happen to me yet), but given enough power cycles (and perhaps some random unknown factors), the bug seems more likely to appear. The bug is that the SSD becomes mostly unresponsive to most ATA commands, and shows as having 8MB (not GB) capacity. It is called the "8MB bug".

It seems people have reported this to Intel in May, perhaps earlier. So Intel knows about it. But they haven't issued any statements or warnings about it, and have not recalled the drives nor have they issued updated firmware. Rumor is that a fix is forthcoming in about a month, but no official word even on that. So I used to think a great deal of Intel on reliability and customer support, but my opinion of them has gone down quite a bit after this. If Intel issues a fix soon, they will partially redeem themselves, but not completely, since I do not like the way they have handled the situation at all.

http://communities.intel.com/thread/22227?tstart=0
http://www.pcreview.co.uk/forums/do-...-t4035508.html

[One_Hertz]

I'm actually a bit down on Intel and the 320 SSD recently. A bug has shown up in the Intel 320 SSDs. It is somewhat random, but seems to be related to power-cycling, perhaps unsafe power cycles, perhaps sleep or hibernation. As far as I can tell, on any given power cycle the bug is unlikely to appear (at least I haven't had it happen to me yet), but given enough power cycles (and perhaps some random unknown factors), the bug seems more likely to appear. The bug is that the SSD becomes mostly unresponsive to most ATA commands, and shows as having 8MB (not GB) capacity. It is called the "8MB bug".

It seems people have reported this to Intel in May, perhaps earlier. So Intel knows about it. But they haven't issued any statements or warnings about it, and have not recalled the drives nor have they issued updated firmware. Rumor is that a fix is forthcoming in about a month, but no official word even on that. So I used to think a great deal of Intel on reliability and customer support, but my opinion of them has gone down quite a bit after this. If Intel issues a fix soon, they will partially redeem themselves, but not completely, since I do not like the way they have handled the situation at all.

http://communities.intel.com/thread/22227?tstart=0
http://www.pcreview.co.uk/forums/do-...-t4035508.html

Doing a quick search, there seems to only be a handful of users with this issue and pcreview got their SSD to this state by power cycling it for 2-3 hours straight, which no user would ever do. This is a completely insignificant problem.

[johnw]

Doing a quick search, there seems to only be a handful of users with this issue and pcreview got their SSD to this state by power cycling it for 2-3 hours straight, which no user would ever do. This is a completely insignificant problem.

That is not at all clear. It could be that the probability of the bug occurring is constant for each power cycle. So every time you power cycle the SSD, you may be risking the bug. Certainly there are people posting about the bug in the thread I linked who only power cycled a few times.

We also don't know what the return rates are for the 320s. Maybe in a few months we will see how prevalent this bug is. In the meantime, I do not like the way Intel has handled it. That I know for certain.

[Anvil]

...
Or about 1 in 1342 bytes written is not 4K aligned. I wonder where that ratio comes from. Is that the ratio of random bytes written to total bytes written by Anvil's app?

The random writes are always aligned so if there are any they would have to be caused by sequential writes.
Wrt writing, the files should always be aligned but there can be partial writes, one doesn't write 4KB just because the file is say 12bytes.
The 12byte file will still take a full cluster which normally is 4KB, in the end it is handled by the file system.

I'm working on that MD5 routine, should be ready within the next few days. (maybe tomorrow)

--

131.79TB Host writes
MWI 28

Still at 6 reallocated sectors.

I've had a long weekend , meanwhile it's been working through the TB's, MB/s is down to 32.8MB/s on avg for ~44hours. (~4.94TiB)
Will let it run for another 12 hours just to see how the avg changes.

[johnw]

Wrt writing, the files should always be aligned but there can be partial writes, one doesn't write 4KB just because the file is say 12bytes.
The 12byte file will still take a full cluster which normally is 4KB, in the end it is handled by the file system.

Good point. Do you know what NTFS does if a program requests a write of, say, 1KiB? We know the cluster it is stored in will be 4KiB, but does NTFS actually pad the 1KiB with zeros so it can write 8 LBAs? Or does it just write the two LBAs that are required, and ignore the other 6 LBAs in the cluster?

If NTFS does the latter, I think the Micron firmware would record that as a non-aligned 4K write, even though it was aligned, since it was less than 4KiB in length.

Can you estimate what fraction of your app's random writes would be 7 LBAs (3584 Bytes) or less?

[One_Hertz]

Good point. Do you know what NTFS does if a program requests a write of, say, 1KiB?

The rest of the cluster is padded with zeroes.

[bulanula]

Two things I am really looking forward to :

-johnw's Samsung and going below MWI of 0
-vapor's C300 testing start and screenshots of SMART attributes so we can compare them to the M4 eg things like factory bad block counts which will matter too in the 25nm vs 34nm debate!

Thank you all for making this possible !

[Anvil]

Doing a quick search, there seems to only be a handful of users with this issue and pcreview got their SSD to this state by power cycling it for 2-3 hours straight, which no user would ever do. This is a completely insignificant problem.

The 8MB BAD CONTEXT bug is rare, I've actually been bitten by that on a G2, the issue can be googled.
(some were able to just secure erase the drive but mine had to be sent back, it was in this state when it arrived)

Anyways, Why would one wan't to power cycle for hours?
Wonder what would have happened to other SSDs if they were treated like this.