Free Files and disks lessonsFiles and disks · Stage 0 · Files · Step 4
Free space and crash safety
See how the OS tracks free blocks, and how a journal keeps the file system consistent after a crash. About 13 minutes.
A journaling file system crashes after writing a committed journal record but before applying the changes. What happens at the next start?
- AThe journal is replayed, completing the operation
- BThe record is discarded and the file isn't created
- CThe whole disk must be scanned with fsck
Show the answer
The journal is replayed, completing the operation. A committed record is guaranteed to be applied in full.
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