How to change the number of active jobs Netvault can run at one time
Open up NV configurator. Go to schedule manager tab. See option of Max. Simultaneously active jobs. Default is 20. Netvault service must be stopped and restarted before change will take hold.
Lowering this number can be beneficial as it will help use less resources on your server. The only reason you would need to increase this setting, is if you have more than 20 drives that can be written to at the same time. If you run more jobs that this is set to, the some will just show a status of "pending", until one of the other jobs finish, so that they can run.
Do not increase this beyond what you have set in the Process Manager tab under "Number of Progress Buffers Available to Plugins".
However, be forewarned there is a price to pay for setting this number too high. With each job that is active (either writing to media, or waiting for media) it is eating up memory out of the processor buffer pool. The more jobs eating away at this buffer pool the jobs that are actually running can become sluggish, start running slower, possible even become unstable.
A better solution to your problem would be to possibly assign priorities to certain jobs so they will be selected to run ahead of others, or possibly change the starting times of some of the jobs.