Additional storage requirements at the staging location
You must reserve space in the backup host's staging location to store log files. See Configure a temporary staging location.
The required space is directly proportional to the number of tracked objects.
Use this formula to calculate an approximate estimate of the required additional storage space:
Estimated storage size (S) = 2 × Number_of_keys × Average_key_size (in bytes)
For example:
If the Number_of_keys = 1000000, and the average_key_size = 50 bytes
Estimated storage size (S) = 2 × 1000000 × 50 =100,000,000 bytes = 100 MB
For details of maintaining the logs in Ceph, see: Maintaining the log bucket.