What is the most reliable indicator of CPU contention?
Look at a combination of processor utilization and processor queuing. (1) The primary indicator of processor utilization is the % Processor Time Counter in the Processor Object. Note that the _Total instance of the Processor Object is actually the average value over all processors. The System Object in NT 4.0 contains a Counter named % Total Processor Time, which is also the average value over all processors. The thread is the unit of execution in Windows. Each process address space that is launched has at least one thread, and many applications, of course, are multithreaded. There is an operating system function in Windows that keeps track of how CPU time each thread consumes using a sampling technique. Samples are normally taken approximately one or two hundred times per second, which suggests that this technique is probably accurate for measurement intervals of 30 seconds or more. These samples are used to maintain the Thread % Processor Time Counter, once execution time recorded in
