1 files changed, 131 insertions, 0 deletions
diff --git a/intl/benchmarks/head.js b/intl/benchmarks/head.js
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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
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Create an interface to measure iterations for a micro benchmark. These iterations
+ * will then be reported to the perftest runner.
+ *
+ * @param {string} metricName
+ */
+function measureIterations(metricName) {
+  let accumulatedTime = 0;
+  let iterations = 0;
+  let now = 0;
+  return {
+    /**
+     * Start a measurement.
+     */
+    start() {
+      now = Cu.now();
+    },
+    /**
+     * Stop a measurement, and record the elapsed time.
+     */
+    stop() {
+      accumulatedTime += Cu.now() - now;
+      iterations++;
+    },
+    /**
+     * Report the metrics to perftest after finishing the microbenchmark.
+     */
+    reportMetrics() {
+      const metrics = {};
+      metrics[metricName + " iterations"] = iterations;
+      metrics[metricName + " accumulatedTime"] = accumulatedTime;
+      metrics[metricName + " perCallTime"] = accumulatedTime / iterations;
+
+      info("perfMetrics", metrics);
+    },
+  };
+}
+
+let _seed = 123456;
+/**
+ * A cheap and simple pseudo-random number generator that avoids adding new dependencies.
+ * This function ensures tests are repeatable, but can be fed random configurations.
+ *
+ * https://en.wikipedia.org/wiki/Linear_congruential_generator
+ *
+ * It has the following distribution for the first 100,000 runs:
+ *
+ *    0.0 - 0.1: 9948
+ *    0.1 - 0.2: 10037
+ *    0.2 - 0.3: 10049
+ *    0.3 - 0.4: 10041
+ *    0.4 - 0.5: 10036
+ *    0.5 - 0.6: 10085
+ *    0.6 - 0.7: 9987
+ *    0.7 - 0.8: 9872
+ *    0.8 - 0.9: 10007
+ *    0.9 - 1.0: 9938
+ *
+ * @returns {number} float values ranged 0-1
+ */
+function prng() {
+  _seed = Math.imul(_seed, 22695477) + 1;
+  return (_seed >> 1) / 0x7fffffff + 0.5;
+}
+
+/**
+ * The distribution of locales. The number represents the ratio of total users in that
+ * locale. The numbers should add up to ~1.0.
+ *
+ * https://sql.telemetry.mozilla.org/dashboard/firefox-localization
+ */
+const localeDistribution = {
+  "en-US": 0.373,
+  de: 0.129,
+  fr: 0.084,
+  "zh-CN": 0.053,
+  ru: 0.048,
+  "es-ES": 0.047,
+  pl: 0.041,
+  "pt-BR": 0.034,
+  it: 0.028,
+  "en-GB": 0.027,
+  ja: 0.019,
+  "es-MX": 0.014,
+  nl: 0.01,
+  cs: 0.009,
+  hu: 0.008,
+  id: 0.006,
+  "en-CA": 0.006,
+  "es-AR": 0.006,
+  tr: 0.005,
+  el: 0.005,
+  "zh-TW": 0.005,
+  fi: 0.005,
+  "sv-SE": 0.004,
+  "pt-PT": 0.004,
+  sk: 0.003,
+  ar: 0.003,
+  vi: 0.003,
+  "es-CL": 0.002,
+  th: 0.002,
+  da: 0.002,
+  bg: 0.002,
+  ro: 0.002,
+  "nb-NO": 0.002,
+  ko: 0.002,
+};
+
+/**
+ * Go through the top Firefox locales, and pick one at random that is representative
+ * of the Firefox population as of 2021-06-03. It uses a pseudo-random number generator
+ * to make the results repeatable.
+ *
+ * @returns {string} locale
+ */
+function pickRepresentativeLocale() {
+  const n = prng();
+  let ratio = 1;
+  for (const [locale, representation] of Object.entries(localeDistribution)) {
+    ratio -= representation;
+    if (n > ratio) {
+      return locale;
+    }
+  }
+  // In case we fall through the "for" loop, return the most common locale.
+  return "en-US";
+}