jboner

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

jedsundwall

Measured Voice Terms of Service

Amended on 25 January, 2013

1. Your Acceptance of Terms

1.1 Your use of Measured Voice and the Measured Voice web site (collectively referred to as the “Service”), is subject to the terms of a legal agreement (“Terms”) between you and Captura Group Inc., DBA Measured Voice (“Measured Voice”). The following Terms of Services ("TOS") explains the agreement and the terms of that agreement.

1.2 In order to use the Service, you must first agree to the Terms. You may not use the Service if you do not accept the Terms. You can accept the Terms by (a) actually using the Service, or (b) clicking a box where such box is made available to you. If you do not agree to any of the following Terms, please do not use the Service. You should print or otherwise save a copy of these TOS for your records.

ottomata

#!/bin/sh
#
# /etc/init.d/kafka -- startup script for the kafka distributed publish-subscribe messaging system
#
# Written by Alexandros Kosiaris <akosiaris@wikimedia.org>
#
### BEGIN INIT INFO
# Provides:          kafka
# Required-Start:    $local_fs $remote_fs $network
# Required-Stop:     $local_fs $remote_fs $network

staltz

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

---

This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

---

pnc

Using OTP's observer (appmon replacement) remotely

$ ssh remote-host "epmd -names"
epmd: up and running on port 4369 with data:
name some_node at port 58769

Note the running on port for epmd itself and the port of the node you're interested in debugging. Reconnect to the remote host with these ports forwarded:

$ ssh -L 4369:localhost:4369 -L 58769:localhost:58769 remote-host

potatosalad

jwk_map = %{ "kty" => "oct", "k" => :base64url.encode("secret")}
jws_map = %{ "alg" => "HS256" }
jwt_map = %{ "test" => true }
signature = JOSE.JWT.sign(jwk_map, jws_map, jwt_map)
signature_compacted = JOSE.JWS.compact(signature)

{_, signature_map} = JOSE.JWS.expand(signature_compacted)
payload = JOSE.JWT.from(:base64url.decode(Map.get(signature_map, "payload")))

# one-liner version:

olivermt

  def update_company(company, company_params) do
    changeset = Company.changeset(company, company_params)
    if Ecto.Changeset.fetch_change(changeset, :shortname) != :error do
      Logger.debug "Shortname changed"
      #TODO dont allow shortname change if shortname is in use in video addresses
      :ok
    end

    Repo.transaction( fn ->
      case Repo.update(changeset) do

henrik

defmodule Lab do
  defmacro say({:when, _, [message, condition]}) do
    {result, _} = Code.eval_quoted(condition)

    if result do
      quote do
        IO.puts unquote(message)
      end
    end
  end

aaronjensen

# ATTENTION: This is now supported in plug_cowboy as of 2.1.0:
# https://hexdocs.pm/plug_cowboy/Plug.Cowboy.Drainer.html

defmodule DrainStop do
  @moduledoc """
  DrainStop Attempts to gracefully shutdown an endpoint when a normal shutdown
  occurs. It first shuts down the acceptor, ensuring that no new requests can be
  made. It then waits for all pending requests to complete. If the timeout
  expires before this happens, it stops waiting, allowing the supervision tree
  to continue its shutdown order.

andreicristianpetcu

An Ansible summary

Jon Warbrick, July 2014, V3.2 (for Ansible 1.7)

Configuration file

intro_configuration.html

First one found from of