// Flags: --expose-gc --expose-internals

'use strict';

const common = require('../common');

const assert = require('assert');

const os = require('os');

const {

monitorEventLoopDelay,

} = require('perf_hooks');

const { sleep } = require('internal/util');

{

const histogram = monitorEventLoopDelay();

assert(histogram);

assert(histogram.enable());

assert(!histogram.enable());

histogram.reset();

assert(histogram.disable());

assert(!histogram.disable());

}

{

[null, 'a', 1, false, Infinity].forEach((i) => {

assert.throws(

() => monitorEventLoopDelay(i),

{

name: 'TypeError',

code: 'ERR_INVALID_ARG_TYPE',

}

);

});

[null, 'a', false, {}, []].forEach((i) => {

assert.throws(

() => monitorEventLoopDelay({ resolution: i }),

{

name: 'TypeError',

code: 'ERR_INVALID_ARG_TYPE',

}

);

});

[-1, 0, 2 ** 53, Infinity].forEach((i) => {

assert.throws(

() => monitorEventLoopDelay({ resolution: i }),

{

name: 'RangeError',

code: 'ERR_OUT_OF_RANGE',

}

);

});

}

{

const s390x = os.arch() === 's390x';

const histogram = monitorEventLoopDelay({ resolution: 1 });

histogram.enable();

let m = 5;

if (s390x) {

m = m * 2;

}

function spinAWhile() {

sleep(1000);

if (--m > 0) {

setTimeout(spinAWhile, common.platformTimeout(500));

} else {

// Give the histogram a chance to record final samples before disabling.

// This helps on slower systems where sampling may be delayed.

setImmediate(common.mustCall(() => {

histogram.disable();

// The values are non-deterministic, so we just check that a value is

// present, as opposed to a specific value.

assert(histogram.count > 0, `Expected samples to be recorded, got count=${histogram.count}`);

assert(histogram.min > 0);

assert(histogram.max > 0);

assert(histogram.stddev > 0);

assert(histogram.mean > 0);

assert(histogram.percentiles.size > 0);

for (let n = 1; n < 100; n = n + 0.1) {

assert(histogram.percentile(n) >= 0);

}

histogram.reset();

assert.strictEqual(histogram.min, 9223372036854776000);

assert.strictEqual(histogram.max, 0);

assert(Number.isNaN(histogram.stddev));

assert(Number.isNaN(histogram.mean));

assert.strictEqual(histogram.percentiles.size, 1);

['a', false, {}, []].forEach((i) => {

assert.throws(

() => histogram.percentile(i),

{

name: 'TypeError',

code: 'ERR_INVALID_ARG_TYPE',

}

);

});

[-1, 0, 101, NaN].forEach((i) => {

assert.throws(

() => histogram.percentile(i),

{

name: 'RangeError',

code: 'ERR_OUT_OF_RANGE',

}

);

});

}));

}

}

spinAWhile();

}

// Make sure that the histogram instances can be garbage-collected without

// and not just implicitly destroyed when the Environment is torn down.

process.on('exit', global.gc);