RMAN and filesperset

[clinton]

In using RMAN When do you reap the benefits of using the
filesperset parameter when using RMAN?
Is it during recovery time?
The docs that I'm reading tells about the benefits of
filesperset during recovery time but not during backups

NOTE: I'm aware that filesperset groups the backups
in backup sets.Fine, I would like to know the advantages
of doing that.


backup filesperset = 3

[sambavan]

When RMAN performs a recovery, it would first restore the backupsets. So as you can see here if you backup 1 file per backupset, then it would be that RMAN has to restore so many backupsets before it performs the recovery. On the other hand if you specify the # of files per set, then it would be the case that

#backupset = TOTAL# of files/#files_per_set

You always look into the recovery time as your down time concern, not the backup time (considering the scenario that you would be using the hot backups)

The backup time depends on the network bandwith, how many tapes can the media manager can parallely access, how fast they work and etc. RMAN is just a tool that facilitate the backup process made easy and simple.

Sam