Resolution:

CPU sizing depends on the use case and resources available. TIBCO ActiveSpaces uses threads to operate and these, depending on the usage, could be heavily active or idle most of the time. Per space there is a thread and if persistence is used there is another. From those user defined spaces that are actively used, we will need CPU. If there is not enough to scale the threads, they will be doing context switching to make use of the available CPUs. When there is a need to scale up the CPU (by adding a new machine), the "top" utility can provide more information about the CPU usage for a process (top -H -p <pid>). (opiton -H returns CPU usage per thread for a process). If there is a thread that is 100% used, then the thread is maxing out on the CPU and there is a need for adding a new machine to scale up operations. If CPU usage per thread is on the low side, there is nothing to be concerned with regarding CPU sizing.