fork of https://github.com/oxigraph/rocksdb and https://github.com/facebook/rocksdb for nextgraph and oxigraph

Igor Canadi b42cd6bed5 Remove the need for LATEST_BACKUP in BackupEngine ... Summary: In the first implementation of BackupEngine, LATEST_BACKUP was the commit point. The backup became committed after the write to LATEST_BACKUP completed. However, we can avoid the need for LATEST_BACKUP. Instead of write to LATEST_BACKUP, the commit point can be the rename from `meta/<backup_id>.tmp` to `meta/<backup_id>`. Once we see that there exists a file `meta/<backup_id>` (without tmp), we can assume that backup is valid. In this diff, we still write out the file LATEST_BACKUP. We need to do this so that we can maintain backward compatibility. However, the new version doesn't depend on this file anymore. We get the latest backup by `ls`-ing `meta` directory. This diff depends on D41925 Test Plan: Adjusted backupable_db_test to this new behavior Reviewers: benj, yhchiang, sdong, AaronFeldman Reviewed By: sdong Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D42069		10 years ago
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backupable_db.cc	Remove the need for LATEST_BACKUP in BackupEngine	10 years ago
backupable_db_test.cc	Remove the need for LATEST_BACKUP in BackupEngine	10 years ago