File checksums needed?
Posted Dec 16, 2008 1:57 UTC (Tue) by daniel
In reply to: File checksums needed?
Parent article: Tux3: the other next-generation filesystem
There are much more likely failure modes for which file checksums are needed. One is where the disk writes the data to the wrong track. Another is where it doesn't write anything but reports that it did. Another is that the power left the client slightly before the disk drive and the client sent garbage to the drive, which then correctly wrote it.
Scribble on final write is something we plan to detect, by checksumming the commit block. I seem to recall reading that SGI ran into hardware that would lose power to the memory before the drive controller lost its power-good, and had to do something special in XFS to survive it. Better would be if hardware was engineered not to do that.
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