How does Rsync perform on files and directories?
Rsync performs best on the file system directly – backing up normal files and directories. It performs far better than if you were to use Rsync to synchronize a backup file offsite. Let’s look at example to see why that’s the case. Scenario 1: File system with 50,000 files, 50 GB total; 50 files of total size 50 MB have changed. Rsync is able to identify which of the 50 files have changed, and for those files, it determines the in-file deltas. It calculates checksums on 50 MB of data, and the backup can complete in a matter of minutes. The amount of data transferred will be around 20 MB for typical documents. Scenario 2: The file system is backed up via NTBackup, which results in a 50GB bkf file. Rsync will detect that the single bkf file has changed, and needs to determine the in-file deltas. It needs to calculate checksums on 50 GB of data, which may take hours. Additionally, we have found that even if the underlying file system changes very little, about 10% of a bkf file changes fr
