InfoQ: CouchDB and Me
http://www.infoq.com/presentations/katz-couchdb-and-me

In this talk from RubyFringe, Damien Katz explains what drove him to create CouchDB, why he chose Erlang and what made him decide to sell his house to work on Free Software.

Very inspiring.

perfomance and scalability testing of a website

stress test your web app

What is Tsung ? The purpose of Tsung is to simulate users in order to test the scalability and performance of IP based client/server applications. You can use it to do load and stress testing of your servers. (Definition coming from the Tsung website) In this post, I will introduce the use of Tsung in order for you to stress test your web applications. Why Tsung ? Because it’s an Open-Source project and, to tell the truth, mainly because this application has been coded in Erlang which gives Tsung a little advantage on the other tools: it has the potential to simulate A LOT of concurrent requests … without crashing. That’s what we expect from a stress testing app, isn’t it? Let’s start the installation We will need the Perl Templating-Toolkit and the Gnu plotting utility in order to create nice HTML and graphical reports with the result data set. So, back to your command prompt: ~$ sudo apt-get install gnuplot-nox libtemplate-perl libhtml-template-perl libhtml-template-expr-pe

ウェブアプリケーションのパフォーマンステスト用ツール Tsung の使い方

When it comes to developing large systems with many interdependent parts, it’s common nowadays to use “queues.”

Runs as a daemon to link separate apps via a queue. Article includes suggested links.

One MILLION connections !

Riak combines a decentralized key-value store, a flexible map/reduce engine, and a friendly HTTP/JSON query interface to provide a database ideally suited for Web applications.

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Interesting!

Submitted by korfuri

This is the beginning of Learn You Some Erlang for Great Good! Reading this tutorial should be one of your first steps in learning Erlang.

Follow the links and be prepared to have your mind moderately blown.

軽量スレッドブーム到来

erlang

Distributed web hosting via erlang/python

Joe Armstrong and Simon Peyton Jones discuss Erlang and Haskell

Interesting video where Joe Armstrong and Simon Peyton Jones engage in some friendly banter about functional programming and Erlang vs Haskell.

(PNG-Grafik, 784x393 Pixel)

All I want for Christmas is a SQL database with no JOINs, secondary indexes, UNIONs, views, character sets or anything else. Just exact and range primary key lookups, GROUP BY, ORDER BY, LIMIT and SQL_CALC_FOUND_ROWS.

Poor SQL; even with DSLs being the new hotness, people forget that SQL is one of the original domain-specific languages. It's a little verbose, and you might be bored with it, but it's much better than writing low-level mapreduce code.

BERT and BERT-RPC are an attempt to specify a flexible binary serialization and RPC protocol that are compatible with the philosophies of dynamic languages such as Ruby, Python, PERL, JavaScript, Erlang, Lua, etc. BERT aims to be as simple as possible while maintaining support for the advanced data types we have come to know and love. BERT-RPC is designed to work seamlessly within a dynamic/agile development workflow. The BERT-RPC philosophy is to eliminate extraneous type checking, IDL specification, and code generation. This frees the developer to actually get things done.

"BERT and BERT-RPC are an attempt to specify a flexible binary serialization and RPC protocol that are compatible with the philosophies of dynamic languages such as Ruby, Python, PERL, JavaScript, Erlang, Lua, etc. BERT aims to be as simple as possible while maintaining support for the advanced data types we have come to know and love. BERT-RPC is designed to work seamlessly within a dynamic/agile development workflow. The BERT-RPC philosophy is to eliminate extraneous type checking, IDL specification, and code generation. This frees the developer to actually get things done."

Good explanation of how CouchDB indexes.

how couchdb b-trees work internally

"After a small amount of experimentation I was able to make Erlang talk to a web page using pure asynchronous message passing. I think this means the death of the following technologies: comet long-poll AJAX keep-alive sockets"

Erlang's creator anoints websockets (includes example server and client)

After a small amount of experimentation I was able to make Erlang talk to a web page using pure asynchronous message passing.

In the first half of his introduction to actor concurrency, Alex Miller discussed the limitations of shared-state concurrency and explained how the actor model is expressed in Erlang. While Erlang is a nonstarter for many shops, actor implementations do exist for languages that run on the JVM. Find out how actors work and see them implemented using Scala's standard library, Groovy's GParallelizer, and the Java libraries Kilim, ActorFoundry, Actors Guild, and Jetlang.

"This post is the starting point of a series of posts in which I’m going to provide you with all the commands you’ll need to set up an Ubuntu 8.04 server loaded with Erlang, Mochiweb proxied by Nginx. In the same series, I’ll also cover: The basic configuration of Postfix (mail) The use of Imagemagick to create dynamically a captcha for your application The configuration of Bind9 in order to play with the url CNAME"

In this interview filmed during QCon London 2008, Joe Armstrong, designer of Erlang, speaks on various aspects of the Erlang language, presenting its roots, how it compares with other languages and why it has become popular these days due to its native ability to scale on multi core systems.

Joe Armstrong About Erlang

Joe Armstrong

great erlang talks

A test with 200,000 sockets (note it's 100,000 pairs) showed a process size of 2MB, so far so good

Using tokyocabinet as backing store for Mnesia

This is only the 3rd blog post I found about mnesiaex and support for tokyocabinet. The comments are worth reading!

Background on jchrisa's Toast (standalone chat app in CouchDB+JS+HTML)

The point is to show how CouchDB's "databasey" features, because they are implemented using HTTP, can be leveraged to make powerful end-user experiences, with just a minimum of code.

Erlang is a programming language created in the Computer Science lab at Ericsson in Sweden in the late 1980s. The above prompt represents an Erlang shell, where you can try the full power of Erlang (well, sort of). To start this tutorial please type ok.. Please note that in Erlang every instruction must be terminated by a DOT (.), and to have it evaluated type Enter.!

"Erlang is a programming language created in the Computer Science lab at Ericsson in Sweden in the late 1980s. The above prompt represents an Erlang shell, where you can try the full power of Erlang (well, sort of). To start this tutorial please type ok.."