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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
"use strict";
/* exported timeThis */
// Load the shared-head file first.
Services.scriptloader.loadSubScript(
this
);
// Load common.js and promisified-events.js from accessible/tests/mochitest/ for
// all tests.
loadScripts(
{ name: "common.js", dir: MOCHITESTS_DIR },
{ name: "promisified-events.js", dir: MOCHITESTS_DIR }
);
// All the A11Y metrics in tools/performance/PerfStats.h.
const ALL_A11Y_PERFSTATS_MASK =
(1 << 29) |
(1 << 30) |
(1 << 31) |
(1 << 32) |
(1 << 33) |
(1 << 34) |
(1 << 35) |
(1 << 36) |
(1 << 37) |
(1 << 38) |
(1 << 39) |
(1 << 40) |
(1 << 41) |
(1 << 42) |
(1 << 43) |
(1 << 44);
const LOG_PREFIX = "perfMetrics";
function logToPerfMetrics(stat) {
info(`${LOG_PREFIX} | ${JSON.stringify(stat)}`);
}
/**
* Time a function and log how long it took. The given name is included in log
* messages. All accessibility PerfStats metrics are also captured and logged.
* This function may only be called once per task, and we are limited to one
* task per file.
*/
async function timeThis(func) {
const start = performance.now();
ChromeUtils.setPerfStatsCollectionMask(ALL_A11Y_PERFSTATS_MASK);
const journal = {};
// Run the specified testing task
await func();
// Log our total elapsed time
journal.A11Y_TotalTime = performance.now() - start;
const stats = JSON.parse(await ChromeUtils.collectPerfStats());
ChromeUtils.setPerfStatsCollectionMask(0);
// Filter stuff out of stats that we don't care about.
// Filter out the GPU process, since accessibility doesn't do anything there.
stats.processes = stats.processes.filter(process => process.type != "gpu");
for (const process of stats.processes) {
// Because of weird JS -> WebIDL 64 bit number issues, we get metrics here
// that aren't for accessibility. For example, 1 << 32 also gets us 1 << 0.
// Filter those out. Also, filter out any metrics with a count of 0.
process.perfstats.metrics = process.perfstats.metrics.filter(
metric => metric.metric.startsWith("A11Y_") && metric.count > 0
);
}
// Now that we've filtered metrics, remove any processes that have no metrics left.
stats.processes = stats.processes.filter(
process => !!process.perfstats.metrics.length
);
// Also, filter out readings for the blank new tab that gets opened before the
// tab with our test content opens.
// We may get a reading that isn't attached to any URL; this contains
// the startup time for the Accessibility Service which we should keep.
// Our parent process readings have no URL field.
stats.processes = stats.processes.filter(
process =>
process.type == "parent" ||
!process.urls.length ||
!process.urls.includes("about:newtab")
);
// Because our perfstats measure both occurances and timing, log values separately
// under different probe names with different units.
// Also, as the same probes can be triggered in content and parent, append a process
// indicator to the end of each probe name.
for (const process of stats.processes) {
for (const stat of process.perfstats.metrics) {
journal[stat.metric + "_" + process.type] = stat.time;
if (stat.count) {
journal[stat.metric + "_Count_" + process.type] = stat.count;
}
}
}
logToPerfMetrics(journal);
}