mechanisms. There are more detailed sources of such information available through Windows' performance monitoring system (accessible with the perfmon program), which includes more finely grained categorization of CPU usage. A limited subset of the CPU time categorization is also accessible through the Task Manager, which can display CPU usage by CPU, and categorized by time spent in user vs. kernel code. See also List of Microsoft Windows components Idle (CPU) Microsoft Windows HLT (x86 instruction) Process Explorer References Windows NT architecture