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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
/**
* 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.
*
*
* 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.
*
*/
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";
}