Multithreading

I've been asked about the multi-threading capabilities of Networker and in the latest performance guide it states "there can be up to six internal threads invoked at the start of a backup." Does this refer to the nsrd process, nsrexecd process, the save/savegrp process or something else!? I've looked at this with pstack just now and nsrd just reports 2 threads while nsrexecd reports 7 threads and savegrp 1 thread?

If one of you EMC dudes are looking at this you may also want to prompt Debbie to finish the document - see p. 76