staltz

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

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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.

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soheilhy

Virtual Hosts on nginx (CSC309)

When hosting our web applications, we often have one public IP address (i.e., an IP address visible to the outside world) using which we want to host multiple web apps. For example, one may wants to host three different web apps respectively for example1.com, example2.com, and example1.com/images on the same machine using a single IP address.

How can we do that? Well, the good news is Internet browsers

denji

Moved to git repository: https://github.com/denji/nginx-tuning

NGINX Tuning For Best Performance

For this configuration you can use web server you like, i decided, because i work mostly with it to use nginx.

Generally, properly configured nginx can handle up to 400K to 500K requests per second (clustered), most what i saw is 50K to 80K (non-clustered) requests per second and 30% CPU load, course, this was 2 x Intel Xeon with HyperThreading enabled, but it can work without problem on slower machines.

You must understand that this config is used in testing environment and not in production so you will need to find a way to implement most of those features best possible for your servers.

hgfischer

Benchmarking Nginx with Go

There are a lot of ways to serve a Go HTTP application. The best choices depend on each use case. Currently nginx looks to be the standard web server for every new project even though there are other great web servers as well. However, how much is the overhead of serving a Go application behind an nginx server? Do we need some nginx features (vhosts, load balancing, cache, etc) or can you serve directly from Go? If you need nginx, what is the fastest connection mechanism? This are the kind of questions I'm intended to answer here. The purpose of this benchmark is not to tell that Go is faster or slower than nginx. That would be stupid.

So, these are the different settings we are going to compare:

• Go HTTP standalone (as the control group)
• Nginx proxy to Go HTTP
• Nginx fastcgi to Go TCP FastCGI
• Nginx fastcgi to Go Unix Socket FastCGI

andreif

# coding=utf-8
"""
LICENSE http://www.apache.org/licenses/LICENSE-2.0
"""
import datetime
import sys
import time
import threading
import traceback
import SocketServer

padde

OpenVPN on Ubuntu 12.10 at DigitalOcean

Install OpenVPN

sudo apt-get install openvpn

Generate Server Certificates

sudo cp -r /usr/share/doc/openvpn/examples/easy-rsa/2.0 /etc/openvpn/easy-rsa2

cd /etc/openvpn/easy-rsa2

dergachev

OS X Screencast to animated GIF

This gist shows how to create a GIF screencast using only free OS X tools: QuickTime, ffmpeg, and gifsicle.

Instructions

To capture the video (filesize: 19MB), using the free "QuickTime Player" application:

nilium

[
  {
    "keys": ["ctrl+w"],
    "command": "run_multiple",
    "args": {
      "commands": [
        {"command": "find_under_expand", "args": null, "context": "window"},
        {"command": "show_panel", "args": {"panel": "find"}, "context": "window"}
      ]
    }

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

Problematic

# this will install everything as root, so take that into account before you run it

# need cmake, python development headers, ZLib and OpenSSL
sudo apt-get install cmake python2.7-dev zlib1g-dev libssl-dev

mkdir libgit && cd libgit

git clone git://github.com/libgit2/libgit2.git

cd libgit2