Skip to content

Instantly share code, notes, and snippets.

Avatar

Thanos Polychronakis thanpolas

View GitHub Profile
@jboner
jboner / latency.txt
Last active May 17, 2022
Latency Numbers Every Programmer Should Know
View latency.txt
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
@giannisp
giannisp / gist:ebaca117ac9e44231421f04e7796d5ca
Last active May 16, 2022
Upgrade PostgreSQL 9.6.5 to 10.0 using Homebrew (macOS)
View gist:ebaca117ac9e44231421f04e7796d5ca
After automatically updating Postgres to 10.0 via Homebrew, the pg_ctl start command didn't work.
The error was "The data directory was initialized by PostgreSQL version 9.6, which is not compatible with this version 10.0."
Database files have to be updated before starting the server, here are the steps that had to be followed:
# need to have both 9.6.x and latest 10.0 installed, and keep 10.0 as default
brew unlink postgresql
brew install postgresql@9.6
brew unlink postgresql@9.6
brew link postgresql
@ndarville
ndarville / business-models.md
Last active Apr 20, 2022
Business models based on the compiled list at http://news.ycombinator.com/item?id=4924647. I find the link very hard to browse, so I made a simple version in Markdown instead.
View business-models.md

Business Models

Advertising

Models Examples
Display ads Yahoo!
Search ads Google
@SlexAxton
SlexAxton / .zshrc
Last active Mar 29, 2022
My gif workflow
View .zshrc
gifify() {
if [[ -n "$1" ]]; then
if [[ $2 == '--good' ]]; then
ffmpeg -i $1 -r 10 -vcodec png out-static-%05d.png
time convert -verbose +dither -layers Optimize -resize 600x600\> out-static*.png GIF:- | gifsicle --colors 128 --delay=5 --loop --optimize=3 --multifile - > $1.gif
rm out-static*.png
else
ffmpeg -i $1 -s 600x400 -pix_fmt rgb24 -r 10 -f gif - | gifsicle --optimize=3 --delay=3 > $1.gif
fi
else
@jeffrafter
jeffrafter / server.js
Created Aug 28, 2010
Twitter OAuth with node-oauth for node.js+express
View server.js
var express = require('express');
var sys = require('sys');
var oauth = require('oauth');
var app = express.createServer();
var _twitterConsumerKey = "YOURTWITTERCONSUMERKEY";
var _twitterConsumerSecret = "YOURTWITTERCONSUMERSECRET";
function consumer() {
@ahgittin
ahgittin / jsonball.rb
Created Feb 23, 2012
a jekyll tag to parse json files and objects for use as maps subsequently
View jsonball.rb
require 'json'
# JSON parser tag, creating map for use in jekyll markdown
# Alex.Heneveld @ Cloudsoft Corp (remove spaces and add the .com)
# Released under APL 2.0
# usage: {% jsonball varname from TYPE PARAM %}
#
# where TYPE is one of {data,var,file,page}, described below
@domenic
domenic / 1-Domenic.js
Last active Sep 30, 2021
How DI container config should work (in JS)
View 1-Domenic.js
"use strict";
// Domenic needs a Tweeter
function Domenic(tweeter) {
this.tweeter = tweeter;
}
Domenic.inject = ["tweeter"];
Domenic.prototype.doSomethingCool = function () {
return this.tweeter.tweet("Did something cool!");
@desandro
desandro / require-js-discussion.md
Created Jan 31, 2013
Can you help me understand the benefit of require.js?
View require-js-discussion.md

I'm having trouble understanding the benefit of require.js. Can you help me out? I imagine other developers have a similar interest.

From Require.js - Why AMD:

The AMD format comes from wanting a module format that was better than today's "write a bunch of script tags with implicit dependencies that you have to manually order"

I don't quite understand why this methodology is so bad. The difficult part is that you have to manually order dependencies. But the benefit is that you don't have an additional layer of abstraction.


@dhh
dhh / Basecamp-DDOS.md
Last active Jun 28, 2020
Basecamp is under network attack (DDoS)
View Basecamp-DDOS.md

Basecamp was under network attack

The attack detailed below has stopped (for the time being) and almost all network access for almost all customers have been restored. We're keeping this post and the timeline intact for posterity. Unless the attack resumes, we'll post a complete postmortem within 48 hours (so before Wednesday, March 26 at 11:00am central time).

Criminals have laid siege to our networks using what's called a distributed denial-of-service attack (DDoS) starting at 8:46 central time, March 24 2014. The goal is to make Basecamp, and the rest of our services, unavailable by flooding the network with bogus requests, so nothing legitimate can come through. This attack was launched together with a blackmail attempt that sought to have us pay to avoid this assault.

Note that this attack targets the network link between our servers and the internet. All the data is safe and sound, but nobody is able to get to it as long as the attack is being successfully executed. This is like a bunch of people

@mikeal
mikeal / gist:9242748
Last active Jun 23, 2020
Response to Nodejitsu NPM Trademark
View gist:9242748

I've known people at nodejitsu for years, since before the company even existed. I still consider many of them friends. That said, somebody over there has lost their mind.

Trademarks are an important part of open source. They protect the integrity of the trust that is built by any project. A classic example of why this is the case is Firefox. Suppose that a malware producer takes the Firefox codebase, which is free and open source, packages up their malware with it and then releases it as "Firefox". Then they buy search advertising and suddenly their bad and malicious version of Firefox is the first result on search engines across the web. This is clearly a bad thing for Firefox and open source everywhere, but what can Mozilla do to protect their community of users?

> They can't enforce a software license since the use is permitted under the Mozilla Public License. They can, however, enforce on these hypothetical bad actors using their trademark on the word "Fi