mtmn

Someone asked in chat (paraphrased) "I am coming from synchronous online systems, and now am going to work on a queue-based system. What should I be aware of?" This is a (somewhat freely-associated) collection of thoughts, based on my experience at SoundCloud.

Why is IRC distributed across multiple servers?

I have been wondering for a long time why IRC networks have multiple servers. Wouldn't it be simpler just to use a single server?

One of the problems of having multiple servers is that netsplits can occur. Anybody who has been on IRC for a while will have witnessed one. Hundreds of people suddenly ripped out of the chat. This can also screw up channel and user modes, and 'some people' have been known to wait for netsplits in order to takeover channels or enter password protected channels.

So lets compare situation (A) a single IRC server everyone connects to with the current setup people use (B) multiple servers. Let's say you run an IRC network with u = 40,000 users and n = 20 server nodes that people connect to via round robin DNS (meaning that when people resolve the DNS it gives them a random server from the set of 20 to connect to). These are vaguely realistic numbers modelled after libera.chat.

So in (B) you have roughly u/n = 2000 clients connected

Introductory resources

High level overview https://yogthos.github.io/ClojureDistilled.html
An Animated Introduction to Clojure https://markm208.github.io/cljbook/
Interactive tutorial in a browser https://tryclojure.org/
Interactive exercises http://clojurescriptkoans.com/
Clerk notebooks with introductory examples https://github.clerk.garden/anthonygalea/notes-on-clojure
More interactive exercises https://4clojure.oxal.org/
Lambda Island tutorials https://lambdaisland.com/
Functional Programming with Clojure resources https://practicalli.github.io/

SKS Keyserver Network Under Attack

This work is released under a Creative Commons Attribution-NoDerivatives 4.0 International License.

Terminological Note

"OpenPGP" refers to the OpenPGP protocol, in much the same way that HTML refers to the protocol that specifies how to write a web page. "GnuPG", "SequoiaPGP", "OpenPGP.js", and others are implementations of the OpenPGP protocol in the same way that Mozilla Firefox, Google Chromium, and Microsoft Edge refer to software packages that process HTML data.

Who am I?

Monitorama 2018 Talks

Hi I'm Ilan, I work at Datadog, a monitoring and analytics platform for large-scale applications and infrastructure. I've been at Monitorama this week and figured I'd make it easy to find the talks from the conference.

Datadog is hiring! Come join me

Day 1

Optimizing for Learning - Logan McDonald (BuzzFeed)

FFmpeg cheat sheet

A list of useful commands for the FFmpeg command line tool.

Download FFmpeg: https://www.ffmpeg.org/download.html

Full documentation: https://www.ffmpeg.org/ffmpeg.html

Basic conversion

How to compress PDF using ghostscript

As a developer, it bothers me when someone sends me a large pdf file compared to the number of pages. Recently, I recieved a 12MB scanned document for just one letter-sized page... so I got to googlin, like I usually do, and found ghostscript!

to learn more abot ghostscript (gs): https://www.ghostscript.com/

What we are interested in, is the gs command line tool, which provides many options for manipulating PDF, but we are interested in compressign those large PDF's into small yet legible documents.

credit goes to this answer on askubuntu forum: https://askubuntu.com/questions/3382/reduce-filesize-of-a-scanned-pdf/3387#3387?newreg=bceddef8bc334e5b88bbfd17a6e7c4f9

	#EXTM3U
	#EXTINF:-1,BBC - Radio 1
	http://as-hls-ww-live.akamaized.net/pool_01505109/live/ww/bbc_radio_one/bbc_radio_one.isml/bbc_radio_one-audio%3d96000.norewind.m3u8
	#EXTINF:-1,BBC - Radio 1Xtra
	http://as-hls-ww-live.akamaized.net/pool_92079267/live/ww/bbc_1xtra/bbc_1xtra.isml/bbc_1xtra-audio%3d96000.norewind.m3u8
	#EXTINF:-1,BBC - Radio 1Dance
	http://as-hls-ww-live.akamaized.net/pool_62063831/live/ww/bbc_radio_one_dance/bbc_radio_one_dance.isml/bbc_radio_one_dance-audio%3d96000.norewind.m3u8
	#EXTINF:-1,BBC - Radio 1 Anthems (UK Only)
	http://as-hls-uk-live.akamaized.net/pool_11351741/live/uk/bbc_radio_one_anthems/bbc_radio_one_anthems.isml/bbc_radio_one_anthems-audio%3d96000.norewind.m3u8
	#EXTINF:-1,BBC - Radio 2

	#!/usr/bin/env bash

	set -Eeuo pipefail
	trap cleanup SIGINT SIGTERM ERR EXIT

	script_dir=$(cd "$(dirname "${BASH_SOURCE[0]}")" &>/dev/null && pwd -P)

	usage() {
	cat <<EOF
	Usage: $(basename "${BASH_SOURCE[0]}") [-h] [-v] [-f] -p param_value arg1 [arg2...]

	#!/usr/bin/python
	bpf_text = """
	#include <linux/ptrace.h>
	#include <linux/sched.h> /* For TASK_COMM_LEN */

	#include <linux/icmp.h>
	#include <linux/netdevice.h>

	struct probe_icmp_data_t
	{