After you have recognized a processor bottleneck, the next step is to determine whether a single process is monopolizing the processor or whether the processor is consumed by running many processes.
Graphs of Processor: % Processor Time during single and multiple-process bottlenecks are nearly indistinguishable. Queue length isn't much help either, because it tells you more about what isn't running than what is. Moreover, queue length is an indicator of the numbers of threads, not the numbers of processes. The threads of a single, multithreaded process contending with each other and with other processes will produce as long a queue as the threads of several single-threaded processes.
The only clear indicator of how many processes are causing the bottleneck is a log of the processor use by each process over time. Log the Process object, then chart Process: % Processor Time for all processes except Idle and _Total. This will reveal how many (and which) processes are very active during the bottleneck.