monperrus

// allows using all Jquery AJAX methods in Greasemonkey
// inspired from http://ryangreenberg.com/archives/2010/03/greasemonkey_jquery.php
// works with JQuery 1.5
// (c) 2011 Martin Monperrus
// (c) 2010 Ryan Greenberg
//
// Usage:
//   $.ajax({
//     url: '/p/',
//     xhr: function(){return new GM_XHR();},

etorreborre

/** from http://www.reddit.com/r/programming/comments/mlbna/scala_feels_like_ejb_2/c31z0co */
interface Pong<T> {}
class Ping<T> implements Pong<Pong<? super Ping<Ping<T>>>> {
    static void Ping() {
        Pong<? super Ping<Long>> Ping = new Ping<Long>();
    }
}


> javac Ping.java

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

hellerbarde

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

adamloving

0-mail.com
0815.ru
0clickemail.com
0wnd.net
0wnd.org
10minutemail.com
20minutemail.com
2prong.com
30minutemail.com
3d-painting.com

isaacs

var cluster = require('cluster');
var PORT = +process.env.PORT || 1337;

if (cluster.isMaster) {
  // In real life, you'd probably use more than just 2 workers,
  // and perhaps not put the master and worker in the same file.
  cluster.fork();
  cluster.fork();

  cluster.on('disconnect', function(worker) {

aras-p

// Just before switching jobs:
// Add one of these.
// Preferably into the same commit where you do a large merge.
//
// This started as a tweet with a joke of "C++ pro-tip: #define private public",
// and then it quickly escalated into more and more evil suggestions.
// I've tried to capture interesting suggestions here.
//
// Contributors: @r2d2rigo, @joeldevahl, @msinilo, @_Humus_,
// @YuriyODonnell, @rygorous, @cmuratori, @mike_acton, @grumpygiant,

andreadipersio

# inspired by
# Master NGINX - Dimitri Aivaliotis
# http://www.amazon.com/Mastering-NGINX-Dimitri-Aivaliotis-ebook/dp/B00B90PJR4
# Chapter 8 - Switching binaries at runtime

# We get the pid of the 'to be replaced' nginx master process
export nginx_old_pid=`cat /var/run/nginx.pid`

# we send an USR2 signal to tell 'to be replaced' process
# to start a new master process.

acgourley

For several weeks our production deployment (Express, Bookshelf/Knex -> MySQL) was randomly having queries fail resulting in 500 errors and server crashes.

The first issue is that the Knex library was using Pool2 slightly incorrectly, and when a ETIMEDOUT error occurred, it tried to release the pooled connection twice. This would create an exception which would crash express (unless you have a top level error handler defined in your express setup)

In this issue (myndzi/pool2#12 (comment)) filed on pool2 by the author of knex (tgriesser) the author of pool2 (myndzi) points out the error handling issue and created a fork of knex with the fix git+https://github.com/myndzi/knex#double-release

After installing the fix on my server, whenever ETIMEDOUT occured an error would be generated in the expected part of the code so that I could decide to retry the query or fail gracefully. Removing the ETIMEDOUT entirely would be

valefranz

This example can be run here: http://graphgist.neo4j.com/#!/gists/b6a3833a7ec042f77e31 If you use the code or images, please cite: Valentina Franzoni, https://gist.github.com/valefranz/b6a3833a7ec042f77e31

First step: create some authors

//CREATE authors, with name as a property