Maksim Titiaiev Titiaiev

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns             
Compress 1K bytes with Zippy ............. 3,000 ns  =   3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns  =  20 µs
SSD random read ........................ 150,000 ns  = 150 µs

Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs

NOTE: This is no longer an experiment! You can use the accessibility inspector in Chrome Devtools now, including a fantastic color contrast inspection tool. Read more: https://developers.google.com/web/updates/2018/01/devtools#a11y

Just like any good element inspector helps you debug styles, accessibility inspection in the browser can help you debug HTML and ARIA exposed for assistive technologies such as screen readers. There's a similar tool in Safari (and reportedly one in Edge) but I like the Chrome one best.

As an internal Chrome experiment, this tool differs from the Accessibility Developer Tools extension in that it has privileged Accessibility API access and reports more information as a result. You can still use the audit feature in the Chrome Accessibility Developer Tools, or you could use the aXe Chrome extension. :)

To enable the accessibility inspector in Chrome stable:

Сервер в связке Nginx + NodeJs

Данная пошаговая инструкция поможет освоить основы на простом примере

Для справки

Сервер поднимался на Debian 8 c характеристиками:

CPU - 1 ядро x 500 МГц

Google Public NTP [AS15169]:

time.google.com

time1.google.com

time2.google.com

time3.google.com


	/*
	I've wrapped Makoto Matsumoto and Takuji Nishimura's code in a namespace
	so it's better encapsulated. Now you can have multiple random number generators
	and they won't stomp all over eachother's state.

	If you want to use this as a substitute for Math.random(), use the random()
	method like so:

	var m = new MersenneTwister();

	{
	"printWidth": 100,
	"tabWidth": 2,
	"useTabs": false,
	"semi": true,
	"singleQuote": true,
	"trailingComma": "es5",
	"bracketSpacing": true,
	"jsxBracketSameLine": false,
	"arrowParens": "avoid",

	#!/usr/bin/env node

	console.log('yay gist')