About the optimal number of backup streams for MSDP
A backup stream appears as a separate job in the NetBackup Activity Monitor. Various methods exist to produce streams. In NetBackup, you can use backup policy settings to configure multiple streams. The NetBackup for Oracle agent lets you configure multiple streams; also for Oracle the RMAN utilities can provide multiple backup channels.
For client deduplication, the optimal number of backup streams is two.
Media server deduplication can process multiple streams on multiple cores simultaneously. For large datasets in applications such as Oracle, media server deduplication leverages multiple cores and multiple streams. Therefore, media server deduplication may be a better solution when the application can provide multiple streams or channels.
More detailed information about backup streams is available.