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@jboner
jboner / latency.txt
Last active May 11, 2024 04:16
Latency Numbers Every Programmer Should Know
Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference 0.5 ns
Branch mispredict 5 ns
L2 cache reference 7 ns 14x L1 cache
Mutex lock/unlock 25 ns
Main memory reference 100 ns 20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy 3,000 ns 3 us
Send 1K bytes over 1 Gbps network 10,000 ns 10 us
Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD
@igrigorik
igrigorik / webapp.rb
Created November 13, 2010 21:28
Inspired by @JEG2's talk at Rubyconf... Any ruby object, as a webapp! 'Cause we can. :-)
require 'rubygems'
require 'rack'
class Object
def webapp
class << self
define_method :call do |env|
func, *attrs = env['PATH_INFO'].split('/').reject(&:empty?)
[200, {}, send(func, *attrs)]
end
This example shows how to setup an environment running Rails 3 under 1.9.2 with a 'rails3' gem set.
∴ rvm update --head
# ((Open a new shell)) or do 'rvm reload'
# If you do not already have the ruby interpreter installed, install it:
∴ rvm install 1.9.2
# Switch to 1.9.2-head and gemset rails3, create if it doesn't exist.
∴ rvm --create use 1.9.2@rails3