"use strict";
const { TelemetrySession } = ChromeUtils.importESModule(
"resource://gre/modules/TelemetrySession.sys.mjs"
);
const DUMMY_PAGE_DATA_URI = `data:text/html,
Dummy
`;
/**
* Tests the MEMORY_DISTRIBUTION_AMONG_CONTENT probe by opening a few tabs, then triggering
* the memory probes and waiting for the "gather-memory-telemetry-finished" notification.
*/
add_task(async function test_memory_distribution() {
waitForExplicitFinish();
if (SpecialPowers.getIntPref("dom.ipc.processCount", 1) < 2) {
ok(true, "Skip this test if e10s-multi is disabled.");
finish();
return;
}
Services.telemetry.canRecordExtended = true;
let histogram = Services.telemetry.getKeyedHistogramById(
"MEMORY_DISTRIBUTION_AMONG_CONTENT"
);
histogram.clear();
let tab1 = await BrowserTestUtils.openNewForegroundTab(
gBrowser,
DUMMY_PAGE_DATA_URI
);
let tab2 = await BrowserTestUtils.openNewForegroundTab(
gBrowser,
DUMMY_PAGE_DATA_URI
);
let tab3 = await BrowserTestUtils.openNewForegroundTab(
gBrowser,
DUMMY_PAGE_DATA_URI
);
let finishedGathering = new Promise(resolve => {
let obs = function () {
Services.obs.removeObserver(obs, "gather-memory-telemetry-finished");
resolve();
};
Services.obs.addObserver(obs, "gather-memory-telemetry-finished");
});
TelemetrySession.getPayload();
await finishedGathering;
let s = histogram.snapshot();
ok("0 - 10 tabs" in s, "We should have some samples by now in this bucket.");
for (var key in s) {
is(key, "0 - 10 tabs");
let fewTabsSnapshot = s[key];
Assert.greater(
fewTabsSnapshot.sum,
0,
"Zero difference between all the content processes is unlikely, what happened?"
);
Assert.less(
fewTabsSnapshot.sum,
80,
"20 percentage difference on average is unlikely, what happened?"
);
let values = fewTabsSnapshot.values;
for (let [bucket, value] of Object.entries(values)) {
if (bucket >= 10) {
// If this check fails it means that one of the content processes uses at least 20% more or 20% less than the mean.
is(value, 0, "All the buckets above 10 should be empty");
}
}
}
histogram.clear();
BrowserTestUtils.removeTab(tab3);
BrowserTestUtils.removeTab(tab2);
BrowserTestUtils.removeTab(tab1);
finish();
});