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Chip Overclock
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I should also mention, this is not an issue with file system corruption. We can deal with that. Failure modes include: boot blocks or partition blocks being corrupted (we never write to those in the field), or the device quits responding to commands at all (this is when replacing the flash part revives it).
For a slightly different viewpoint: I've had way too much experience with SSDs in the past three and a half or so years. All of it is with high-availability mission-critical embedded devices using surface-mount SSDs with IDE interfaces, quite a different form factor and application from the ones you are probably using. Most of my experience has been bad. The SSDs fail catastrophically after a few hundred power cycles. That's just enough for them to get through system testing, as we were to find out, then fail hard in the field after a few months of use. This is not an issue of exhausting the write-cycles on the underlying flash. We do very few writes, and all the devices we use feature wear-leveling. We know that the failure is in the NAND flash part itself. We can remove the flash from a working SSD and place it in a failing SSD and the failing SSD "revives". The SSD apparently has its own firmware in the NAND flash part, since we cannot use off-the-shelf uninitialized NAND flash parts of the same brand and model to the same effect. Life is not good. I cannot recommend these kinds of SSDs to my clients for these kinds of applications. (Sorry, NDA keeps me from saying much more.)
Ever notice on your typical QWERTY keyboard how ampersand and asterisk are right next to each other? Back in my university sysadmin days I was removing quarterly student accounts from my department's VAX 750 running 4.2 BSD (yes, I am that old). I knew it would take a long time, so I ran the following commands: su cd / rm -rf foo & After a few seconds of wondering why the prompt didn't come back, I turned to my student assistant and said "Get the backup tapes."
Toggle Commented Mar 24, 2010 on The Opposite of Fitts' Law at Coding Horror
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Mar 24, 2010