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tmux cheatsheet

As configured in my dotfiles.

start new:

tmux

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Internet Scale Services Checklist

A checklist for designing and developing internet scale services, inspired by James Hamilton's 2007 paper "On Desgining and Deploying Internet-Scale Services."

http://mvdirona.com/jrh/talksandpapers/jamesrh_lisa.pdf

Basic tenets

Does the design expect failures to happen regularly and handle them gracefully?
Have we kept things as simple as possible?

Endpoints

Linux Hugepages

Hugepages are a hardware feature designed to reduce pressure on the translation lookaside buffer (TLB) for applications that operate on large contiguous memory regions.

Take a program that operates on a large 2MB internal structure as an example. If the program accesses that space in such a way that one byte in each regular 4k page is accessed, 2M/4k = 512 TLB entries are needed. Each TLB miss at the hardware level requires and interrupt and kernel intervention to resolve. However, if the allocation is backed by a 2M hugepage by mmap()ing with MAP_HUGETLB, only 1 TLB entry is required.

On x86_64, there are two hugepage sizes: 2MB and 1G. 1G hugepages are also called gigantic pages. 1G must be enabled on kernel boot line with hugepagesz=1G. Hugeages, especially 1G ones, should to be allocated early before memory fragments (i.e. at/near boot time) to increase the likelihood that they can be allocated successfully with minimal memory migration (i.e. defreg) required

	require 'stringio'
	require 'timeout'

	class Object
	def methods_returning(expected, *args, &blk)
	old_stdout = $>
	$> = StringIO.new

	methods.select do \|meth\|
	Timeout::timeout(1) { dup.public_send(meth, *args, &blk) == expected rescue false } rescue false

	DEPS = $(CURDIR)/deps

	DIALYZER_OPTS = -Wunderspecs

	# List dependencies that should be included in a cached dialyzer PLT file.
	# DIALYZER_DEPS = deps/app1/ebin \
	# deps/app2/ebin

	DEPS_PLT = {{name}}.plt

	%%% -- coding: utf-8; Mode: erlang; tab-width: 4; c-basic-offset: 4; indent-tabs-mode: nil --
	%%% ex: set softtabstop=4 tabstop=4 shiftwidth=4 expandtab fileencoding=utf-8:
	%%%
	%%%------------------------------------------------------------------------
	%%% @doc
	%%% ==Abstract Code Insertion==
	%%% A method to get the abstract code representation directly from the
	%%% binary beam module representation.
	%%%
	%%% Other methods could be used, but they are not as efficient.

	package main

	import (
	"fmt"
	"os"
	"os/exec"
	"syscall"
	)

	func main() {

	#!/bin/bash
	#
	#########################################################################
	#This software code is made available "AS IS" without warranties of any #
	#kind. You may copy, display, modify and redistribute the software #
	#code either by itself or as incorporated into your code; provided that #
	#you do not remove any proprietary notices. Your use of this software #
	#code is at your own risk and you waive any claim against Amazon #
	#Digital Services, Inc. or its affiliates with respect to your use of #
	#this software code. (c) 2006-2007 Amazon Digital Services, Inc. or its #

	package main

	import (
	"bytes"
	"encoding/binary"
	"fmt"
	"golang.org/x/sys/unix"
	"os"
	"syscall"
	)