incremental/delta backups and restore

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Shiva Bhanujan

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Jul 13, 2017, 6:47:15 PM7/13/17

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Hello,

I'm trying to do an incremental backup to a target DIR, such that only the delta is written to the new target. When trying to do backups, the latest backup contains the entire backup set as opposed to a delta.

eg.

put(k1,v1)

backup

put(k2,v2)

backup

restore

k1,v1

k2,v2

what I want, is that I can restore only the delta, which means, k2,v2 only.

Is there a way such that I can restore only the delta?

Regards,

Shiva

Andrew Kryczka

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Jul 21, 2017, 2:32:57 PM7/21/17

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Hi,

RocksDB backups are physical not logical, i.e., they're aware of the files but not of the keys/values contained in the files. Considering that our backups are physical, they are incremental. E.g.,

- flush 000001.sst

- backup

- flush 000002.sst

- backup

The first file, 000001.sst, will only be backed up once. Both backup 1's and backup 2's meta-files will point to the same copy of 000001.sst.

You can read more details about backup here: https://github.com/facebook/rocksdb/wiki/How-to-backup-RocksDB%3F. Let me know if you have more questions!