Jakub Arnold darthdeus

Profiling performance

Using perf:

$ perf record -g binary
$ perf script | stackcollapse-perf.pl | rust-unmangle | flamegraph.pl > flame.svg

NOTE: See @GabrielMajeri's comments below about the -g option.

Memory Optimization (Christer Ericson, GDC 2003)
http://realtimecollisiondetection.net/pubs/GDC03_Ericson_Memory_Optimization.ppt

Cache coherency primer (Fabian Giesen)
https://fgiesen.wordpress.com/2014/07/07/cache-coherency/

Code Clinic 2015: How to Write Code the Compiler Can Actually Optimize (Mike Acton)
http://gdcvault.com/play/1021866/Code-Clinic-2015-How-to

To remove a submodule you need to:

Delete the relevant section from the .gitmodules file.
Stage the .gitmodules changes git add .gitmodules
Delete the relevant section from .git/config.
Run git rm --cached path_to_submodule (no trailing slash).
Run rm -rf .git/modules/path_to_submodule (no trailing slash).
Commit git commit -m "Removed submodule "
Delete the now untracked submodule files rm -rf path_to_submodule

Using OTP's observer (appmon replacement) remotely

$ ssh remote-host "epmd -names"
epmd: up and running on port 4369 with data:
name some_node at port 58769

Note the running on port for epmd itself and the port of the node you're interested in debugging. Reconnect to the remote host with these ports forwarded:

$ ssh -L 4369:localhost:4369 -L 58769:localhost:58769 remote-host

This runs a build for a small elixir (phoenix) project in about 40 seconds by caching as much of the compiled files as possible.

We've been using this for months in multiple projects without any issues. Please ping be if there is any issues with this script and I'll update it.

It should be generic enough to work on any elixir app using mix.

If you have a elixir_buildpack.config, then enable that section in the build script to keep versions in sync!

2016-08-09: Updated to newer Erlang and Elixir and fixed curl command.

	syntax on
	set ruler " Show the line and column numbers of the cursor.
	set formatoptions+=o " Continue comment marker in new lines.
	set textwidth=0 " Hard-wrap long lines as you type them.
	set modeline " Enable modeline.
	set esckeys " Cursor keys in insert mode.
	set linespace=0 " Set line-spacing to minimum.
	set nojoinspaces " Prevents inserting two spaces after punctuation on a join (J)
	" More natural splits
	set splitbelow " Horizontal split below current.

	# In order for gpg to find gpg-agent, gpg-agent must be running, and there must be an env
	# variable pointing GPG to the gpg-agent socket. This little script, which must be sourced
	# in your shell's init script (ie, .bash_profile, .zshrc, whatever), will either start
	# gpg-agent or set up the GPG_AGENT_INFO variable if it's already running.

	# Add the following to your shell init to set up gpg-agent automatically for every shell
	if [ -f ~/.gnupg/.gpg-agent-info ] && [ -n "$(pgrep gpg-agent)" ]; then
	source ~/.gnupg/.gpg-agent-info
	export GPG_AGENT_INFO
	else

	"""
	Minimal character-level Vanilla RNN model. Written by Andrej Karpathy (@karpathy)
	BSD License
	"""
	import numpy as np

	# data I/O
	data = open('input.txt', 'r').read() # should be simple plain text file
	chars = list(set(data))
	data_size, vocab_size = len(data), len(chars)

	# fshow - git commit browser (enter for show, ctrl-d for diff, ` toggles sort)
	fshow() {
	local out shas sha q k
	while out=$(
	git log --graph --color=always \
	--format="%C(auto)%h%d %s %C(black)%C(bold)%cr" "$@" \|
	fzf --ansi --multi --no-sort --reverse --query="$q" \
	--print-query --expect=ctrl-d --toggle-sort=\`); do
	q=$(head -1 <<< "$out")
	k=$(head -2 <<< "$out" \| tail -1)

	#!/bin/bash

	#
	# bash script to run yesod-dev's auto reload inside ghci (faster template reloading)
	#
	# see also https://github.com/yesodweb/yesod/issues/754
	#
	# needs tmux and fswatch, tested on MacOS 10.10
	#