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diff --git a/testsuites/rhealstone/taskswitch/taskswitch.adoc b/testsuites/rhealstone/taskswitch/taskswitch.adoc new file mode 100644 index 0000000000..9b2d10a40c --- /dev/null +++ b/testsuites/rhealstone/taskswitch/taskswitch.adoc @@ -0,0 +1,27 @@ +== Task Switch Benchmark + +This benchmark measures the average time it takes the system to switch between +two independent and active tasks of equal priority. Task switching is synchronous +and non-preemptive. + +=== Directives + + * rtems_task_wake_after + + +=== Methodology + +This benchmark utilizes rtems_task_wake_after( RTEMS_YIELD_PROCESSOR ) to +achieve a synchronous, non-preemptive task switch. rtems_task_wake_after +used in this context is essentially just a yield. + +As this is an average, we structure the benchmark code in a way that results +in some overhead being included that inflates the total elapsed time. This +overhead includes: + * the time it takes to iterate through the for loops (minimal + * overhead code in rtems_task_wake_after + +We instantiate two tasks, and time how long it takes for them to switch back +and forth between themselves a total of BENCHMARKS * 2 times. We then use +the put_time call to divide this total elapsed time by BENCHMARKS * 2, giving +an average, and subtract out the overhead time we found earlier. |