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Archive for July, 2009

Webhooks behind the firewall with Reverse HTTP

With the growing popularity of building webhooks to link applications together, and the stunning ease of building web applications with lightweight web frameworks in various languages (such as Sinatra in Ruby), the thorny issue of NAT-firewalls remains a substantial dampener on development ease. Enter another use for Reverse HTTP. With Reverse HTTP, applications running behind a firewall can be attached to a public server without any firewall changes, and accessed as if they belonged to the public server.

Brought to you through the magic of the Ruby Rack interface, I’d like to announce Hookout. Hookout provides an adapter for Rack-based ruby applications to make the application directly available to the outside world via a Reverse HTTP server.

Read more…


Rabbit on the treadmill: Run Rabbit, Run!

For the last couple of months I’ve been working on rewriting RabbitMQ’s persister so that it will scale to volumes of data that won’t fit in RAM, and will perform consistently across a wide variety of use cases. This work is coming to a conclusion now, and although the code is not yet released, nor has it even been through QA, benchmarking it thoroughly is useful to allow us to understand what’s good and what’s bad about the new design. In this post I’m not going to do any before and after comparisons — they’ll be coming in due course. Instead, I’m going use RabbitMQ to benchmark harddiscs — an SSD, and a normal rotating harddisc. As someone said at the presentation we gave at the recent Erlang Factory, “using SSDs are just like RAM”. Cue expectations of a turbo-charged, overclocked, overvolted Rabbit, with liquid nitrogen cooling. Read more…


BBC Feeds Hub slides from London Erlang Factory

As part of a talk on Erlang at the BBC at Erlang Factory London, Sean O’Halpin gave an introduction to the BBC Feeds Hub project.

His talk introduced the essential problem we are trying to solve, and ran through the domain model and the corresponding architecture.

Here are the slides:

(or download them as a PDF).

Those links are


Achieving Scale with Messaging and the Cloud

On the 9th, last Thursday, I spoke at the Online Gaming High Scalability SIG at Skills Matter. The talk covered

– an introduction to Messaging (what it’s for, why you might like to use it),
– a couple of pointers in the directions of examples of Messaging being used at scale in the cloud, and
– the main part of the talk, an overview of techniques for scaling up Messaging-based distributed systems.

The slides are available for download here (PDF – with notes), and are also available on SlideShare:

View more documents from leastfixedpoint.



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