rendering-starvation.html | Explore in Territory

<!doctype html>
<title>Blink Scheduler Rendering Starvation Policy</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="resources/utils.js"></script>

<script>
'use strict';

window.onload = () => {
  promise_test(async t => {
    await requestAnimationFramePromise();

    // Post tasks before the rendering is complete to not affect scheduler's
    // starvation tracking.
    const NUM_TASKS = 50;
    const TASK_DURATION_MS = 10;
    let taskCount = 0;

    const controller = new TaskController();
    t.add_cleanup(() => controller.abort());

    for (let i = 0; i < NUM_TASKS; i++) {
      const p = scheduler.postTask(() => {
        ++taskCount;
        spin(TASK_DURATION_MS);
      }, {signal: controller.signal});
      ignoreUnhandledRejection(p);
    }

    // Wait for after BeginMainFrame so the scheduler resets the starvation
    // duration.
    await scheduler.yield();
    const start = performance.now();
    await requestAnimationFramePromise();
    const duration = performance.now() - start;

    // Check that we're close enough to the upper bound of the starvation
    // threshold (100 ms). This includes some slack, but it's well below the
    // total potential blocking task time (500 ms), and good enough to catch
    // regressions.
    assert_less_than(duration, 130);
    assert_less_than(taskCount, 50);
    assert_greater_than(taskCount, 0);
  }, 'Test that rendering is not starved by normal priority tasks');
};

</script>
chromium/third_party/blink/web_tests/wpt_internal/scheduler/integration_tests/rendering-starvation.html
