SSD Data Integrity

[Magic Carpet]

What happens when you cut the power (while doing a read/write), does it lead to data corruption / bad cells / etc?

Recovery/repair?

 

[Zap]

It can lead to data corruption if it was in the middle of a write. Coincidentally, the same thing can happen to a HDD. Just sayin'.

 

[Magic Carpet]

It can lead to data corruption if it was in the middle of a write. Coincidentally, the same thing can happen to a HDD. Just sayin'.

Well, a mechanical drive may also develop a bad block. I am curious, as to what might happen to SSD hardware under extreme conditions? Does a "cell" go down or something?

I have to replace my 2.5" drives quite often (they survive about 2 years), because of shock, vibration and "power outages". But... this is a known animal to me. I haven't done experiments on SSDs yet. Sure as hell, things aren't as rosy as manufactures make them to be.

 

[BrightCandle]

I haven't seen any data.

In terms of vibration and shock you should find that the SSD's are better than a HDD since its just silicon. I say this however but I also know most SSDs dont die because of the memory itself but because the controller or connectors fails - they may not be mechanically well put together.

As to cutting power mid write its likely to loose more data, but deal with it better. The remapping of the sectors is the write to worry about as a potential corruption there could make the drives contents very corrupt.

Would love to hear what you find out.

 

[Zap]

Actually, if you're paranoid about power loss... either leave the battery in your notebook or use a UPS with your desktop.

Alternately, find some "enterprise" SSD that uses a capacitor which can complete pending writes in case of power loss.

 

[nk215]

SSD uses the ram to write cache data. You run a risk of data lost when you cut power. Because it doesn't take long to empty the cache, the chance of you losing data is small but it is still there.

Some SSDs have capacitors to protect you against such situation.

 

[Diogenes2]

....Alternately, find some "enterprise" SSD that uses a capacitor which can complete pending writes in case of power loss.

Some SSDs have capacitors to protect you against such situation.

I think there is an echo in here...

 

[capeconsultant]

I believe the Intel 320 has a capacitor. Not sure about the 520, which is what I have.

 

[LeftSide]

There was an article I just read that said they found some major data loss with power loss. Something like a 50% chance in certain instances. I'm going to try and find it.

 

[LeftSide]

Depending upon when you lose power, you can get silent data corruption. If it happens during an erase it corrupts the next write! Data corruption that can happen months after the power loss.

http://cseweb.ucsd.edu/users/swanson/papers/DAC2011PowerCut.pdf


"6. CONCLUSION
The flash memory devices we studied in this work demonstrated
unexpected behavior when power failure occurs. The error rates do
not always decrease as the operation proceeds, and power failure
can corrupt the data from operations that completed successfully.
We also found that relying on blocks that have been programmed or
erased during a power failure is unreliable, even if the data appears
to be intact."

 

[ShintaiDK]

Well, a mechanical drive may also develop a bad block. I am curious, as to what might happen to SSD hardware under extreme conditions? Does a "cell" go down or something?

HDs dont get bad blocks due to powercut.

 

[ShintaiDK]

I believe the Intel 320 has a capacitor. Not sure about the 520, which is what I have.

Yep. Cacheless SSDs and SSDs with caps is much more reliable here.