Nagios Monitoring for Erlang

December 30, 2009 A few notes about a short project to support active Nagios checks for Erlang nodes, applications and process groups.

Filed under erlang

Replicating receive-after in an Erlang gen_server

December 13, 2009 Very brief post on how to reproduce the behavior of receive-after in an Erlang gen_server. Useful for recurring tasks.

Filed under erlang

Durable Writes & Consistent Reads

December 1, 2009 In this second part in the "Hands On Review of the Dynamo Paper" we take a look at only acknowledging update to user after it has been written to multiple stores, and comparing read values from multiple sources to ensure consistent reads.

Filed under erlangdistributed-systems

Hands On Review of the Dynamo Paper

November 30, 2009 Instead of just listing off the myriad interesting ideas in the Amazon Dynamo paper, I decided it would be more interesting for both myself and readers to actually walk through implementing a distributed key-value store and incrementally evolve it using the ideas introduced in the Amazon Dynamo paper.

Filed under erlangdistributed-systems

Recurring Events and Message Passing

November 25, 2009 This article looks at a couple of approaches for implementing systems with recurring events using message-passing based concurrency (Erlang and Clojure are used in code snippets). In particular it looks at the ping-pong, circle, coordinator and gossip approaches to distributed communication.

Filed under actorserlangclojureagentsconcurrency

Scalable Scraping in Clojure

November 24, 2009 A fairly indepth tutorial which takes a look at using Clojure to extract data from webpages, using agents to process data, and a few other knickknacks.

Filed under screen-scrapingclojureagentsconcurrency

A Couple of Clojure Agent Examples

November 22, 2009 This post contains an extremely brief discussion on how Clojure agents differ from Erlang actors, and then follows with examples o fusing Clojure agents to serialize file writes, form message relays and perform parallel HTTP fetches.

Filed under actorsclojureagentsconcurrency

Writing Files in Clojure

November 16, 2009 Another quick Clojure blog entry, this one on writing out file contents.

Filed under clojure

Reading Files in Clojure

November 16, 2009 A brief overview to approaches to reading in files in Clojure.

Filed under clojure

Setting Up TLA+ Tools on OS X

October 31, 2009 A quick walkthrough for setting up the TLA+ tools on OS X.

Filed under tla

Comments on "Why Engineers Should Consider Formal Methods"

October 20, 2009 A few quick comments on the excellent paper from 1997, "Why Engineers Should Consider Formal Methods".

Filed under computer-sciencesoftware-engineering