It just reduces CPU usage on YouTube.
As of
// ==UserScript==
// @name YouTube CPU Tamer
// @name:ja YouTube CPU Tamer
// @name:zh-CN YouTube CPU Tamer
// @namespace knoa.jp
// @description It just reduces CPU usage on YouTube.
// @description:ja YouTubeでのCPU使用率を削減します。
// @description:zh-CN 减少YouTube页面上的CPU利用率。
// @include https://www.youtube.com/*
// @include https://www.youtube.com/embed/*
// @include https://www.youtube-nocookie.com/embed/*
// @version 1
// @grant none
// @run-at document-start
// ==/UserScript==
/*
[update]
[memo]
interval
interval 自体のインスタンスを減らすためにすべて1つの関数にまとめて実行する。
前面タブなら1秒ごと、背面タブなら60秒ごとに頻度を落とす。
timeout
前面タブではユーザーインタラクションに関わる場合があるのでそのまま実行する。
背面タブなら最初の10秒はUI生成のためにそのまま実行するが、以降は完全に無視する。
*/
(function(){
const SCRIPTID = 'YouTubeCpuTamer';
console.log(SCRIPTID, location.href);
const BUNDLEDINTERVAL = 1000;/* the bundled interval */
const BACKGROUNDINTERVAL = 60*1000;/* take even longer interval on hidden tab */
const INITIALIZINGTIME = 10*1000;/* it should allow background timeouts for initializing UI of YouTube on load */
/*
[interval]
*/
/* integrate each of intervals */
const bundle = {};/* {0: {f, interval, lastExecution}} */
let index = 0;/* use it instead of interval id */
let lastExecution = 0;
/* bundle intervals */
const originalSetInterval = window.setInterval.bind(window);
window.setInterval = function(f, interval, ...args){
//console.log(SCRIPTID, 'original interval:', interval);
bundle[index] = {
f: f.bind(null, ...args),
interval: interval,
lastExecution: 0,
};
return index++;
};
window.clearInterval = function(id){
//console.log(SCRIPTID, 'clearInterval:', id);
delete bundle[id];
};
/* execute bundled intervals */
/* a bunch of intervals does cost so much even if the processes do nothing */
originalSetInterval(function(){
const now = Date.now();
if(document.hidden && now < lastExecution + BACKGROUNDINTERVAL) return;
Object.keys(bundle).forEach(id => {
const item = bundle[id];
if(item === undefined) return;/* it could be occur on tiny deletion chance */
if(now < item.lastExecution + item.interval) return;/* not yet */
item.f();
item.lastExecution = now;
});
lastExecution = now;
}, BUNDLEDINTERVAL);
/*
[timeout]
*/
/* kill the background timeouts after initializing */
const originalSetTimeout = window.setTimeout.bind(window);
const started = Date.now()
let initialized = false;
window.setTimeout = function(f, timeout, ...args){
//console.log(SCRIPTID, 'timeout:', timeout);
if(document.hidden){
/* do nothing after initializing */
/* should return true for tricking YouTube as succeeded */
if(initialized) return true;
if(started + INITIALIZINGTIME < Date.now()) return initialized = true;
}
return originalSetTimeout(f, timeout, ...args);
};
})();