Now, suppose you have 12 cores per CPU and thus total of 24 cores on dual CPU. And you want to utilize only 12 cores to run the solution. In that case, it does not mean that it will utilize all 12 cores of one CPU and leave other CPU free. Actually, it selects total 12 cores from both CPUs in combination depending on the availability. This combination/distribution of cores can not be controlled manually and it is done automatically at OS level. So in short, there is no way to control the utilization of just one CPU. You can define the number of cores for running your job, but it is picked automatically from each CPU.