un33k

FILE SPACING:

 # double space a file
 sed G

 # double space a file which already has blank lines in it. Output file
 # should contain no more than one blank line between lines of text.
 sed '/^$/d;G'

dahlbyk

[alias]
	dt = difftool
	mt = mergetool
[diff]
	tool = bc3
[difftool]
	prompt = false
[difftool "bc3"]
	cmd = \"c:/program files (x86)/beyond compare 3/bcomp.exe\" \"$LOCAL\" \"$REMOTE\"
[difftool "p4"]

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

MohamedAlaa

tmux shortcuts & cheatsheet

start new:

tmux

start new with session name:

tmux new -s myname

groovybayo

Step by step guide to setting up IDEA to write gatling simulations

Prerequisites:

Have [SBT plugin][sbt-plugin] installed

Begin

• [Create a new project][create-project] in IDEA ( File > New Project ...)
  • Make sure you select a maven module

alexclear

#!/usr/bin/perl
use strict;
use warnings;

print "Processing ${ARGV[0]}, filtering domain ${ARGV[1]}\n";
open INPUT, ${ARGV[0]} or die $!;
open OUTPUT, ">${ARGV[0]}.filtered.xml" or die $!;

my $skip = 0;
while (my $line = <INPUT>) {

kenee

#!/bin/sh

TSUNG=/usr/local/tsung/bin/tsung
CONF=/data/httpd/tsung/etc/test.d.xml
LOG=/data/httpd/tsung/log

/usr/bin/screen -d -m $TSUNG -f $CONF -l $LOG start

willurd

Each of these commands will run an ad hoc http static server in your current (or specified) directory, available at http://localhost:8000. Use this power wisely.

Discussion on reddit.

Python 2.x

$ python -m SimpleHTTPServer 8000

emiller

#!/bin/bash
#
# git-mv-with-history -- move/rename file or folder, with history.
#
# Moving a file in git doesn't track history, so the purpose of this
# utility is best explained from the kernel wiki:
#
#   Git has a rename command git mv, but that is just for convenience.
#   The effect is indistinguishable from removing the file and adding another
#   with different name and the same content.