Service Worker Performance Tests
Our performance tests are mochitests running in the mozperftest
harness. Tests reside under dom/serviceworkers/test/performance,
itemized in perftest.toml. Beyond the standard mochitest machinery,
performance tests define a perfMetadata variable at the top level, and call:
info("perfMetrics", JSON.stringify(metrics));
to report their results, where metrics is a map from testpoint name to scalar numeric value. See the performance scripts documentation for more.
They can be run via mach perftest, or as normal mochitests via mach test. (Currently we can’t run the full manifest, see bug 1865852.)
Adding new tests
Add files to perftest.toml as usual for mochitests.
Modify linux.yml, macosx.yml, and windows11.yml under taskcluster/kinds/perftest. Currently, each test needs to be added individually to the run command (here, for example). kind.yml can be ignored–it provides some defaults.
Add your new test to perfdocs/config.yml.
Modify the generated documentation using:
$ ./mach lint -l perfdocs . --fix --warnings --outgoing
There’s currently a bug which will likely cause the command to fail. Running it a second time should succeed.
Profiler Markers
Profiler markers can be used to collect timing data. Markers of known name can be inspected from the perftest. AUTO_PROFILER_MARKER_TEXT must be used, as we need both the start-time and end-time of the marker. For example:
AUTO_PROFILER_MARKER_TEXT("interesting thing #1", DOM, {}, ""_ns);
AUTO_PROFILER_MARKER_TEXT("interesting thing #2", DOM, {}, ""_ns);
can be inspected from the perftest:
await startProfiler();
interestingThings();
let pdata = await stopProfiler();
let duration_ms = inspectProfile(pdata, [
"interesting thing #1",
"interesting thing #2"
]);
Staging tests in try jobs
$ ./mach try fuzzy --full
Look for ‘service-worker to find things like:
Results
Results can be found in treeherder on mozilla-central and autoland. Look for linux-sw, macosx-sw, and win-sw (example). These symbol names are defined in the .yml files under taskcluster/kinds/perftest.