log_test.js

"use strict";
const fs = require('fs');
const util = require('util');
const slice = [].slice;
const format = util.format;

const unloggedIterationCount = 10000000;
const loggedIterationCount = 10000;

const fileName = './test.log';

const testObject = {
    once: 'upon', a: 'time'
};

function log_simple(level, msg) {
    if(level) {
        fs.appendFileSync(fileName, msg + '\n');
    }
}

function log_closure(level, f) {
    if(level) {
        fs.appendFileSync(fileName, f() + '\n');
    }
}

function log_format(level /*, args */) {
    if(level) {
        fs.appendFileSync(fileName, format.apply(null, slice.call(arguments, 1)) + '\n');
    }
}

function time_simple() {
    console.log('Starting test: simple');
    console.log('Starting unlogged test: simple');
    const unloggedStartTime = Date.now();
    for(let i = 0; i < unloggedIterationCount; i++) {
        log_simple(false, 'This is a simple test message; iteration = ' + i + '; obj = ' + JSON.stringify(testObject));
    }
    const unloggedEndTime = Date.now();
    console.log('Ending unlogged test: simple: time elapsed = ' + (unloggedEndTime - unloggedStartTime) + ' ms');

    console.log('Starting logged test: simple');
    const loggedStartTime = Date.now();
    for(let i = 0; i < loggedIterationCount; i++) {
        log_simple(true, 'This is a simple test message; iteration = ' + i + '; obj = ' + JSON.stringify(testObject));
    }
    const loggedEndTime = Date.now();
    console.log('Ending logged test: simple: time elapsed = ' + (loggedEndTime - loggedStartTime) + ' ms');
}

function time_closure() {
    console.log('Starting test: closure');
    console.log('Starting unlogged test: closure');
    const unloggedStartTime = Date.now();
    for(let i = 0; i < unloggedIterationCount; i++) {
        log_closure(false, () => 'This is a closure test message; iteration = ' + i + '; obj = ' + JSON.stringify(testObject));
    }
    const unloggedEndTime = Date.now();
    console.log('Ending unlogged test: closure: time elapsed = ' + (unloggedEndTime - unloggedStartTime) + ' ms');

    console.log('Starting logged test: closure');
    const loggedStartTime = Date.now();
    for(let i = 0; i < loggedIterationCount; i++) {
        log_closure(true, () => 'This is a closure test message; iteration = ' + i + '; obj = ' + JSON.stringify(testObject));
    }
    const loggedEndTime = Date.now();
    console.log('Ending logged test: closure: time elapsed = ' + (loggedEndTime - loggedStartTime) + ' ms');
}

function time_format() {
    console.log('Starting test: format');
    console.log('Starting unlogged test: format');
    const unloggedStartTime = Date.now();
    for(let i = 0; i < unloggedIterationCount; i++) {
        log_format(false, 'This is a format test message; iteration = %d; obj = %j', i, testObject);
    }
    const unloggedEndTime = Date.now();
    console.log('Ending unlogged test: format: time elapsed = ' + (unloggedEndTime - unloggedStartTime) + ' ms');

    console.log('Starting logged test: format');
    const loggedStartTime = Date.now();
    for(let i = 0; i < loggedIterationCount; i++) {
        log_format(true, 'This is a format test message; iteration = %d; obj = %j', i, testObject);
    }
    const loggedEndTime = Date.now();
    console.log('Ending logged test: format: time elapsed = ' + (loggedEndTime - loggedStartTime) + ' ms');
}

time_simple();
time_closure();
time_format();

/****** Results *****
 * node log_test.js
 *  Starting test: simple
 *  Starting unlogged test: simple
 *  Ending unlogged test: simple: time elapsed = 9792 ms
 *  Starting logged test: simple
 *  Ending logged test: simple: time elapsed = 665 ms
 *  Starting test: closure
 *  Starting unlogged test: closure
 *  Ending unlogged test: closure: time elapsed = 1846 ms
 *  Starting logged test: closure
 *  Ending logged test: closure: time elapsed = 504 ms
 *  Starting test: format
 *  Starting unlogged test: format
 *  Ending unlogged test: format: time elapsed = 450 ms
 *  Starting logged test: format
 * Ending logged test: format: time elapsed = 609 ms
 *****************/