To start with, RMAN performance tuning is related to when it's doing operations such as backup and restore. Anything can make such operations slower and if that happens, you will need to detect the bottleneck and use optimizations which can enhance the performance. It becomes even more important that RMAN can deliver a great performance because nowadays, the size of an average database is in multiterabytes and as backups work on 24/7 basis, any slowness won't be acceptable to the management.
There are several factors which can appear as a bottleneck for RMAN performance. For example, an I/O bottleneck from the storage, the type of backup that you have configured, whether the backup or restore job involves parallelism, and so on. In addition to these factors, RMAN may not be performing well even due to factors which are not under your direct control, such as a slow network or less bandwidth from the storage device. In the next section, we will first look at the...