Context Switches/sec is the combined rate at which all processors on the computer are switched from one thread to another.
Context switches occur when a running thread voluntarily relinquishes the processor, is preempted by a higher priority ready thread, or switches between user-mode and privileged (kernel) mode to use an Executive or subsystem service.
It is the sum of Thread\\\\Context Switches/sec for all threads running on all processors in the computer and is measured in numbers of switches.
There are context switch counters on the System and Thread objects. This counter displays the difference between the values observed in the last two samples, divided by the duration of the sample interval.