How does a system with a worn-out flash behave? I know this is an overly-broad question...
I've got a Linux system running ext3 on an industrial CF card. I've pared the unneeded system activity down and I'm estimating that the CF in this application should last more than five years (based on vmstat
-d write counts).
So in the meeting I said we'd probably want to visit our field instalations after five years and replace the flash cards. And they asked "how can we really tell if the flash is worn out?"
Um - good question.
So, what happens with a worn-out CF card? Do writes actually fail with an I/O error, or is the data just garbled or lost? Does it hang, timeout? Do reads report CRC errors, or silently return incorrect data? Is it dependent on CF vendors, product types, etc? Is there a (non-destructive) test that will tell you if a card is worn out?