Md. Sumon Islam sumonst21

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

Concat MP4 files without transcoding to mpeg

Use the h264_mp4toannexb bitstream filter to convert the mp4s (video steam only) into the AnnexB bitstream format
```
ffmpeg -i input1.mp4 -vcodec copy -vbsf h264_mp4toannexb -acodec copy part1.ts
# repeat for up to inputN
```
Concat the files using cat

	<?php
	/**
	* Convert a comma separated file into an associated array.
	* The first row should contain the array keys.
	*
	* Example:
	*
	* @param string $filename Path to the CSV file
	* @param string $delimiter The separator used in the file
	* @return array

	<?php
	namespace clutch;

	class Request {

	/**
	* The url of the request
	* @var string
	*/
	public $url;

	#
	# Wide-open CORS config for nginx
	#
	location / {

	if ($request_method = 'OPTIONS') {

	add_header 'Access-Control-Allow-Origin' '*';

	#

	/*
	* Inspired by: http://stackoverflow.com/questions/4360060/video-streaming-with-html-5-via-node-js
	*/

	var http = require('http'),
	fs = require('fs'),
	util = require('util');

	http.createServer(function (req, res) {
	var path = 'video.mp4';

	-------------------------------------
	PayPal Standard Subscription Sign-up
	-------------------------------------

	[txn_type] => subscr_signup
	[subscr_id] => I-NARPL1C0KAHA
	[last_name] => User
	[residence_country] => US
	[mc_currency] => AUD
	[item_name] => Digital Subscription

	# Nginx can serve FLV/MP4 files by pseudo-streaming way without any specific media-server software.
	# To do the custom build we use 2 modules: --with-http_secure_link_module --with-http_flv_module
	# This module "secure-link" helps you to protect links from stealing away.
	#
	# NOTE: see more details at coderwall: http://coderwall.com/p/3hksyg

	cd /usr/src
	wget http://nginx.org/download/nginx-1.5.13.tar.gz
	tar xzvf ./nginx-1.5.13.tar.gz && rm -f ./nginx-1.5.13.tar.gz

	<?php
	/**
	* Timing Class for benchmarking in PHP
	* @ref: http://www.if-not-true-then-false.com/2010/php-timing-class-class-for-measure-php-scripts-execution-time-and-php-web-page-load-time/
	*/
	class Timing {
	private $break;
	private $start_time;
	private $stop_time;

	#!/bin/sh
	## backup each mysql db into a different file, rather than one big file
	## as with --all-databases. This will make restores easier.
	## To backup a single database simply add the db name as a parameter (or multiple dbs)

	## Putting the script in /var/backups/mysql seems sensible... on a debian machine that is
	## Create the user and directories
	# mkdir -p /var/backups/mysql/databases
	# useradd --home-dir /var/backups/mysql --gid backup --no-create-home mysql-backup
	## Remember to make the script executable, and unreadable by others