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Color me puzzled

Posted Nov 12, 2009 13:58 UTC (Thu) by ebiederm (subscriber, #35028)
Parent article: Supporting transactions in btrfs

Aren't transactions with rollbacks just.

- Snapshot the fs.

Perform operations.

- Snapshot the fs (aka commit), or rollback to the previous snapshot.

Then the code that needs to have a consistent view of what is
correct looks at the snapshot.

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Color me puzzled

Posted Nov 14, 2009 1:30 UTC (Sat) by giraffedata (subscriber, #1954) [Link]

Aren't transactions with rollbacks just. - Snapshot the fs. Perform operations. - Snapshot the fs (aka commit), or rollback to the previous snapshot.

If there's only one transaction at a time going on. But if there are other filesystem updates happening while the transaction runs, you don't want to roll those back because the one transaction failed.