ephekt

Backend Architectures

Twitter

ror, scala, jetty, erlang, thrift, mongrel, comet server, my-sql, memchached, varnish, kestrel(mq), starling, gizzard, cassandra, hadoop, vertica, munin, nagios, awstats

• Scaling Twitter: Making Twitter 10000 Percent Faster
• Scaling Twitter
• Blaine Cook on Scaling Twitter - YouTube

ephekt

def add1(arr, val, n)
  # how many times are we going to increment
  increment_count = n == 0 ? arr.length : n.abs
  # are we going up or down the array
  indices = n < 0 ? (-1..-arr.length) : (0...arr.length)
  # iterate and update the array in place
  indices.each do |index|
    if (arr_value = arr[index]) == val
      arr[index] = arr_value + 1
      # decrement and check the count all in one go

ephekt

def add1(arr, val, n)
  stop  = arr.length - 1
  count = 0

  (0..stop).each do |i|
    index = n < 0 ? stop - i : i

    if arr[index] == val
      arr[index] += 1

ephekt

function interval(duration, fn){
  this.baseline = undefined
  
  this.run = function(){
    if(this.baseline === undefined){
      this.baseline = new Date().getTime()
    }
    fn()
    var end = new Date().getTime()
    this.baseline += duration