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@anildigital
anildigital / gist:862675ec1b7bccabc311
Created July 26, 2014 18:27
Remove dangling docker images
docker rmi $(docker images -q -f dangling=true)
@larsmans
larsmans / hellinger.py
Created July 15, 2012 13:25
Hellinger distance for discrete probability distributions in Python
"""
Three ways of computing the Hellinger distance between two discrete
probability distributions using NumPy and SciPy.
"""
import numpy as np
from scipy.linalg import norm
from scipy.spatial.distance import euclidean
@hellerbarde
hellerbarde / latency.markdown
Created May 31, 2012 13:16 — forked from jboner/latency.txt
Latency numbers every programmer should know

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

@jboner
jboner / latency.txt
Last active October 21, 2025 18:15
Latency Numbers Every Programmer Should Know
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
@aemkei
aemkei / LICENSE.txt
Last active March 7, 2025 20:08 — forked from 140bytes/LICENSE.txt
Binary Tetris - 140byt.es
DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
Version 2, December 2004
Copyright (C) 2011 YOUR_NAME_HERE <YOUR_URL_HERE>
Everyone is permitted to copy and distribute verbatim or modified
copies of this license document, and changing it is allowed as long
as the name is changed.
DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
@juniorz
juniorz / import.rb
Created January 5, 2012 10:15 — forked from ngauthier/import.rb
Import a blogger archive to jekyll (octopress version)
require 'rubygems'
require 'nokogiri'
require 'fileutils'
require 'date'
require 'uri'
# usage: ruby import.rb my-blog.xml
# my-blog.xml is a file from Settings -> Basic -> Export in blogger.
data = File.read ARGV[0]
@cpatni
cpatni / app.rb
Created November 21, 2011 22:39
unique calculation using redis
require 'sinatra'
require 'redis'
require 'json'
require 'date'
class String
def &(str)
result = ''
result.force_encoding("BINARY")
@ryanb
ryanb / github_tree_slider.js
Created December 6, 2010 17:23
This is how GitHub's new AJAX file browser works.
GitHub.TreeSlider = function () {
if (window.history && window.history.pushState) {
function a() {
if (e.sliding) {
e.sliding = false;
$(".frame-right").hide();
$(".frame-loading:visible").removeClass("frame-loading")
}
}
if (!($("#slider").length == 0 || !GitHub.shouldSlide)) if (!navigator.userAgent.match(/(iPod|iPhone|iPad)/)) {
require 'redis'
# SADD key, member
# Adds the specified <i>member</i> to the set stored at <i>key</i>.
redis = Redis.new
redis.sadd 'my_set', 'foo' # => true
redis.sadd 'my_set', 'bar' # => true
redis.sadd 'my_set', 'bar' # => false
redis.smembers 'my_set' # => ["foo", "bar"]