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Diffstat (limited to 'testsuites/rhealstone/rhmlatency/rhmlatency.adoc')
| -rw-r--r-- | testsuites/rhealstone/rhmlatency/rhmlatency.adoc | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/testsuites/rhealstone/rhmlatency/rhmlatency.adoc b/testsuites/rhealstone/rhmlatency/rhmlatency.adoc new file mode 100644 index 0000000000..fd445ca3ff --- /dev/null +++ b/testsuites/rhealstone/rhmlatency/rhmlatency.adoc @@ -0,0 +1,22 @@ += Message Latency Benchmark + +This benchmark measures the intertask message latency. This is the delay within +RTEMS between a running task using the rtems_message_queue to send a message to +a waiting task and that task waking up and receiving the message. + +== Directives + + * rtems_message_queue_send + * rtems_message_queue_receive + + +== Methodology + +This benchmark consists of a high priority task and a low priority task. The +benchmark starts in the high priority task, which blocks on a call to rtems_ +message_queue recieve. By accounting for the overhead of the task switch from +the high priority task to the low priority task, and the actual time to recieve +the message, the intertask message latency is found. + +The average is found and the overhead (the time of the first run) is subtracted +out in the call to put_time. |