zephyr/tests/benchmarks/latency_measure
Anas Nashif 3ae52624ff license: cleanup: add SPDX Apache-2.0 license identifier
Update the files which contain no license information with the
'Apache-2.0' SPDX license identifier.  Many source files in the tree are
missing licensing information, which makes it harder for compliance
tools to determine the correct license.

By default all files without license information are under the default
license of Zephyr, which is Apache version 2.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2019-04-07 08:45:22 -04:00
..
src benchmarks: latency_measure: convert from k_alert to workqueue 2019-01-16 21:34:07 -05:00
CMakeLists.txt license: cleanup: add SPDX Apache-2.0 license identifier 2019-04-07 08:45:22 -04:00
README.txt
prj.conf tests: CONFIG_TEST_USERSPACE now off by default 2019-04-06 14:30:42 -04:00
prj_small_freq_divider.conf tests: CONFIG_TEST_USERSPACE now off by default 2019-04-06 14:30:42 -04:00
testcase.yaml

README.txt

Title: Latency Measurement

Description:

This benchmark measures the latency of selected capabilities

IMPORTANT: The sample output below was generated using a simulation
environment, and may not reflect the results that will be generated using other
environments (simulated or otherwise).


Sample Output:

***** BOOTING ZEPHYR OS v1.7.99 - BUILD: Mar 24 2017 22:46:05 *****
|-----------------------------------------------------------------------------|
|                            Latency Benchmark                                |
|-----------------------------------------------------------------------------|
|  tcs = timer clock cycles: 1 tcs is 10 nsec                                 |
|-----------------------------------------------------------------------------|
| 1 - Measure time to switch from ISR back to interrupted thread              |
| switching time is 12591 tcs = 125910 nsec                                   |
|-----------------------------------------------------------------------------|
| 2 - Measure time from ISR to executing a different thread (rescheduled)       |
| switch time is 8344 tcs = 83440 nsec                                        |
|-----------------------------------------------------------------------------|
| 3 - Measure average time to signal a sema then test that sema               |
| Average semaphore signal time 63 tcs = 638 nsec                             |
| Average semaphore test time 49 tcs = 498 nsec                               |
|-----------------------------------------------------------------------------|
| 4- Measure average time to lock a mutex then unlock that mutex              |
| Average time to lock the mutex 107 tcs = 1078 nsec                          |
| Average time to unlock the mutex 92 tcs = 929 nsec                          |
|-----------------------------------------------------------------------------|
| 5 - Measure average context switch time between threads using (k_yield)       |
| Average thread context switch using yield 110 tcs = 1107 nsec                 |
|-----------------------------------------------------------------------------|
| 6 - Measure average context switch time between threads (coop)              |
| Average context switch time is 88 tcs = 882 nsec                            |
|-----------------------------------------------------------------------------|
===================================================================
PROJECT EXECUTION SUCCESSFUL