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Flash Destroyer Tests Limit of Solid State Storage
An anonymous reader writes "We all know that flash and other types of solid state storage can only endure a limited number of write cycles. The open source Flash Destroyer prototype explores that limit by writing and verifying a solid state storage chip until it dies. The total write-verify cycle count is shown on a display — watch a live video feed and guess when the first chip will die. This project was inspired by the inevitable comments about flash longevity on every Slashdot SSD story. Design files and source are available at Google Code."
Mechanical disks have lots of great failure modes. You can do seek tests until the arm breaks or voice coil fails, you can do write/read tests until you get enough bad sectors that they can't recover the data any more, or you can do start-stop of the drive motor until it dies. Another good one is to stop the motor for a while, then see if it starts up or has stiction (sic), but that test takes a long time. If the drive is not held rigidly enough, vibration will kill it, and it it isn't cooled properly, heat will kill it. Did I miss any?
And honestly it's a pretty valid argument. This is definitely going to be informative, but I'm just as interested in how a particular SSD handles the flash blocks failing as when they fail. A SSD with flash that averages 1,000,000 writes before blocks start to fail but does it gracefully with little/no data loss could be better than one that averages 2,000,000 but goes out in a blaze of glory as soon as the first block fails.
"Always forgive your enemies; nothing annoys them so much." - Oscar Wilde
Or connect the drive inside any computer running a Prescott P4 with 100% CPU utilization.
Tequila: It's not just for breakfast anymore!
Graceful as in data not related to your recent failed writes are still readable so they can be backed up and migrated to a new drive. Not sure why that concept is so difficult. I consider something dead as "completely unreadable, ALL your data has been destroyed - have a nice day."
No longer reliable but still semi recoverable isn't quite "dead."
Maybe I'm just using a stricter interpretation of the word dead than you are?
Let's use a marker on a white board analogy. If I was storing all my data on a suitably large white board using a marker and I completely exhausted my marker's supply of ink, I'd be pissed if this resulted in a blank whiteboard, wouldn't you? On that same note, if I wiped a small section of my whiteboard with the intent of writing something new in that area and only then realized that my marker was no longer suitably supplied with ink and my write failed, I would find the blank void in that section alone acceptable.
Does that clarify things?