Data maintenance transaction rollbacks

1. A system, comprising:

one or more processors configured to:

receive a first transaction that modifies or deletes first data stored in a storage system;

determine that the first data is subject to an intervening re-arrangement transaction; and

in response to determining that the first data is subject to the intervening re-arrangement transaction,

rollback the intervening re-arrangement transaction at least with respect to the first data; and

commit the first transaction; and

a memory coupled to the one or more processors and configured to provide the one or more processors with instructions.

2. The system of claim 1 , wherein the intervening re-arrangement transaction is a compaction of the first data with second data.

3. The system of claim 1 , wherein the intervening re-arrangement transaction creates third data based at least in part on compaction of at least the first data with second data.

4. The system of claim 3 , wherein rolling back of the intervening re-arrangement transaction comprises removing the first data from the third data.

5. The system of claim 1 , wherein the one or more processors are further configured to:

determine, based at least in part on the first transaction, that the first data is to be modified or deleted in connection with the first transaction.

6. The system of claim 5 , wherein the one or more processors are further configured to:

in response to determining that the first data is to be modified or deleted in connection with the first transaction, determine whether the first data is subject to one or more intervening re-arrangement transactions.

7. The system of claim 6 , wherein:

determining whether the first data is subject to the one or more intervening re-arrangement transactions comprises querying a log of the one or more intervening re-arrangement transactions; and

wherein the log of the one or more intervening re-arrangement transactions comprises a mapping of the one or more intervening re-arrangement transactions to data subject to corresponding re-arrangement transactions.

8. The system of claim 1 , wherein:

the intervening re-arrangement transaction is a compaction of the first data with one or more other data; and

rolling back the intervening re-arrangement transaction at least with respect to the first data comprises:

rolling back the intervening re-arrangement transaction with respect to the first data and one or more data.

9. The system of claim 1 , wherein:

the intervening re-arrangement transaction is a compaction of the first data with one or more other data; and

rolling back the intervening re-arrangement transaction at least with respect to the first data comprises:

rolling back the intervening re-arrangement transaction with respect to the first data and a first subset of one or more data.

10. The system of claim 9 , wherein a second subset of the one or more data is not rolled back.

11. The system of claim 9 , wherein a second subset of the one or more data is still subject to the compaction after the rolling back of the intervening re-arrangement transaction with respect to the first data and the first subset of the one or more data.

12. The system of claim 1 , wherein:

rolling back the intervening re-arrangement transaction at least with respect to the first data comprises:

determining one or more policies pertaining to one or more of (i) the intervening re-arrangement transaction, and (ii) rolling back the intervening re-arrangement transactions; and

determining whether to roll-back the intervening re-arrangement transaction based at least in part on the one or more policies; and

wherein the intervening re-arrangement transaction is rolled back at least with respect to the first data in response to determining to roll-back the intervening re-arrangement transaction based at least in part on the one or more policies.

13. The system of claim 12 , wherein an extent to which the intervening re-arrangement transaction rolled back is based at least in part on the one or more policies.

14. The system of claim 1 , wherein in response to a determination that the first data subject is subject to a plurality of intervening re-arrangement transactions, the plurality of intervening re-arrangement transactions are respectively rolled back at least with respect to the first data.

15. The system of claim 14 , wherein the plurality of intervening arrangement transactions are completely rolled back.

16. The system of claim 1 , wherein:

rolling back the intervening re-arrangement transaction at least with respect to the first data comprises:

querying a user for an indication to rollback the intervening re-arrangement transaction; and

the intervening re-arrangement transaction is rolled back at least with respect to the first data in response to receipt of the indication to rollback the intervening re-arrangement transaction from the user.

17. The system of claim 16 , wherein the user is queried for the indication to rollback the intervening re-arrangement transaction in response to determining that a state of the storage system satisfies one or more predefined criteria.

18. The system of claim 1 , wherein rolling back the intervening re-arrangement transaction at least with respect to the first data comprises:

updating an index mapping of files with respect to at least the first data so that an index mapping points to a location of the first data before the intervening re-arrangement transaction.

19. A method, comprising:

receiving, by one or more processors, a first transaction that modifies or deletes first data stored in a storage system;

determining that the first data is subject to an intervening re-arrangement transaction; and

in response to determining that the first data is subject to the intervening re-arrangement transaction,

rolling back the intervening re-arrangement transaction at least with respect to the first data; and

committing the first transaction.

20. A computer program product embodied in a non-transitory computer readable medium and comprising computer instructions for:

receiving, by one or more processors, a first transaction that modifies or deletes first data stored in a storage system;

determining that the first data is subject to an intervening re-arrangement transaction; and

in response to determining that the first data is subject to the intervening re-arrangement transaction,

rolling back the intervening re-arrangement transaction at least with respect to the first data; and

committing the first transaction.