Edward Ribeiro eribeiro

edit: see http://cs.brown.edu/~sk/Memos/Examining-Reproducibility/

Not deserving of a full post, but nonetheless worth writing about: @ongardie, @aalevy, and a few others on Twitter were surprised by the number of papers that were flagged as "not reproducible" according to the recent study at http://reproducibility.cs.arizona.edu. Digging deeper, it appeared that 1.) "code builds" is the standard for reproducibility in this study and that 2.) many broken builds were the result of missing dependencies on the researchers' systems.

I tried reproducing a few of the authors' "unreproducible" results. It's hard to vet 600+ research code repositories, but, with a little effort (< ~10 minutes each?), I was able to get all of the following to actually build (on Ubuntu 13.10). This doesn't inspire confidence in the reproducibility of the study results.

Peter [email protected]

["Quantifying the Mismatch between Emerging Scale-Out Applications and Modern Processors" in TOCS](http://reproducibility.cs.ariz

Adding 2 nodes to an existing 3-node ZooKeeper ensemble without losing the Quorum

Since many deployments may start out with 3 nodes and so little is known about how to grow a cluster from 3 memebrs to 5 members without losing the existing Quorum, here is an example of how this might be achieved.

In this example, all 5 nodes will be running on the same Vagrant host for the purpose of illustration, running on distinct configurations (ports and data directories) without the actual load of clients.

YMMV. Caveat usufructuarius.

Step 1: Have a healthy 3-node ensemble

A friend asked me for a few pointers to interesting, mostly recent papers on data warehousing and "big data" database systems, with an eye towards real-world deployments. I figured I'd share the list. It's biased and rather incomplete but maybe of interest to someone. While many are obvious choices (I've omitted several, like MapReduce), I think there are a few underappreciated gems.

###Dataflow Engines:

Dryad--general-purpose distributed parallel dataflow engine
http://research.microsoft.com/en-us/projects/dryad/eurosys07.pdf

Spark--in memory dataflow
http://www.cs.berkeley.edu/~matei/papers/2012/nsdi_spark.pdf

	GFS = HDFS
	MapReduce = Hadoop
	BigTable = HBase
	Protocol Buffers = Thrift or Avro (serialization)
	Stubby = Thrift or Avro (RPC)
	ColumnIO = Parquet
	Dremel = Impala
	Chubby = Zookeeper
	Omega = Mesos
	Borg = Aurora

	- [ ] Math
	- [ ] Linear Algebra
	- [ ] Lay - Linear Algebra
	- [ ] 18.06 Linear Algebra
	http://www.scotthyoung.com/blog/mit-challenge/#more-link1806
	- [ ] Burke Lecture Notes
	http://www.math.washington.edu/~burke/crs/407/lectures/
	- [ ] Coding The Matrix
	http://www.amazon.com/dp/0615880991/?tag=coursera-course198-20
	- [ ] Quantifying Uncertainty

	"""
	Get a bunch of Crunchbase data, but respect the API limits.

	Author JD Maturen
	Apache 2 License
	"""
	import logging
	from random import random
	import sys

	Inside your parent pom.xml:

	<build>
	<pluginManagement>
	<plugins>
	<plugin>
	<groupId>org.apache.maven.plugins</groupId>
	<artifactId>maven-compiler-plugin</artifactId>
	<version>2.3.2</version>
	</plugin>

	# $unixtime 1354232717
	# local Thu 29 Nov 2012 03:45:17 PM PST utc Thu 29 Nov 2012 11:45:17 PM GMT
	unixtime ()
	{
	gawk "BEGIN { print \"local\", strftime("'"'"%c"'"'", $1), \"utc\", strftime("'"'"%c"'"'", $1, 1) ; }"
	}
	# Alternately,
	# $date -d @1354298146
	# Fri Nov 30 09:55:46 PST 2012

	// Source: https://groups.google.com/forum/#!topic/angular/hVrkvaHGOfc
	// jsFiddle: http://jsfiddle.net/pkozlowski_opensource/PxdSP/14/
	// author: Pawel Kozlowski

	var myApp = angular.module('myApp', []);

	//service style, probably the simplest one
	myApp.service('helloWorldFromService', function() {
	this.sayHello = function() {
	return "Hello, World!"