Ryoma Kawajiri rkawajiri

My thoughts on MessagePack

Hi. My name is Sadayuki "Sada" Furuhashi. I am the author of the MessagePack serialization format as well as its implementation in C/C++/Ruby.

Recently, MessagePack made it to the front page of Hacker News with this blog entry by Olaf, the creator of the Facebook game ZeroPilot. In the comment thread, there were several criticisms for the blog post as well as MessagePack itself, and I thought this was a good opportunity for me to address the questions and share my thoughts.

My high-level response to the comments

To the best of my understanding, roughly speaking, the criticisms fell into the following two categories.

tmux shortcuts & cheatsheet

start new:

tmux

start new with session name:

tmux new -s myname

OS X Screencast to animated GIF

This gist shows how to create a GIF screencast using only free OS X tools: QuickTime, ffmpeg, and gifsicle.

Instructions

To capture the video (filesize: 19MB), using the free "QuickTime Player" application:

Skinny Framework ハンズオンで出た質問と回答

IDE の Debugger どうやったら使えるの？

ハンズオン中はごめんなさいをするしかなかったのですが、 Skinny Framework 1.0.6 から使えるようになりました！

$ ./skinny debug [port]

ActiveRecord: Store Milliseconds (or Microseconds) in Timestamps with Rails / MySQL

Milliseconds in your Timestamps.

We got 'em, you want 'em.

Why

Shit needs to be PRECISE

LICENSE

MIT

	namespace :db do
	namespace :sqlseed do
	desc "drop database and reload seeds"
	task :load do
	# is this what im looking for?
	# FileList['db/seed.sql']

	conf = Rails.configuration.database_configuration[Rails.env]

	system "mysql -u#{conf['username']} #{conf['database']} <<ENDMYSQL

	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

	# Open the existing Xcode project
	project_file = product_name + '.xcodeproj'
	project = Xcodeproj::Project.new(project_file)

	# Add a file to the project in the main group
	file_name = 'Message.m'
	group_name = product_name
	file = project.new_file(file_name, group_name)

	# Add the file to the main target

	// from http://scratch99.com/web-development/javascript/convert-bytes-to-mb-kb/
	function bytesToSize(bytes) {
	var sizes = ['Bytes', 'KB', 'MB', 'GB', 'TB'];
	if (bytes == 0) return 'n/a';
	var i = parseInt(Math.floor(Math.log(bytes) / Math.log(1024)));
	if (i == 0) return bytes + ' ' + sizes[i];
	return (bytes / Math.pow(1024, i)).toFixed(1) + ' ' + sizes[i];
	};

	static BOOL PSPDFIsDevelopmentBuild(void) {
	#if TARGET_IPHONE_SIMULATOR
	return YES;
	#else
	static BOOL isDevelopment = NO;
	static dispatch_once_t onceToken;
	dispatch_once(&onceToken, ^{
	// There is no provisioning profile in AppStore Apps.
	NSData *data = [NSData dataWithContentsOfFile:[NSBundle.mainBundle pathForResource:@"embedded" ofType:@"mobileprovision"]];
	if (data) {