//de digitalextremist

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

Install NGINX

# Install software-properties-common package to give us add-apt-repository package
sudo apt-get install -y software-properties-common

# Install latest nginx version from community maintained ppa
sudo add-apt-repository ppa:nginx/stable

# Update packages after adding ppa
sudo apt-get update

	module System
	extend self
	def cpu_count
	return Java::Java.lang.Runtime.getRuntime.availableProcessors if defined? Java::Java
	return File.read('/proc/cpuinfo').scan(/^processor\s*:/).size if File.exist? '/proc/cpuinfo'
	require 'win32ole'
	WIN32OLE.connect("winmgmts://").ExecQuery("select * from Win32_ComputerSystem").NumberOfProcessors
	rescue LoadError
	Integer `sysctl -n hw.ncpu 2>/dev/null` rescue 1
	end

	# Signal catching
	def shut_down
	puts "\nShutting down gracefully..."
	sleep 1
	end

	puts "I have PID #{Process.pid}"

	# Trap ^C
	Signal.trap("INT") {