Four short links: 26 June 2009

Biz Numbers, Progress, Curse of the Mummy Tweets, and Crime Viz

by Nat Torkington | @gnat | comments: 0

1. Size vs Growth vs Acceleration (Rowan Simpson) -- you can tell how well a company is doing by the basis on which they report their progress.
2. Engineers Are The Best Deal, So Stock Up On Them (TechCrunch) -- Software engineers today are about 200-400% more productive than software engineers were 10 years ago because of open source software, better programming tools, common libraries, easier access to information, better education, and other factors. This means that one engineer today can do what 3-5 people did in 1999! (via Simon Willison)
3. Livetweeting a Mummy CT Scan -- this is why I love my Brooklyn Museum's 1stfans membership--I know that I'm supporting the museum with the coolest online outreach.
4. 20 Visualizations to Understand Crime (Flowing Data) -- thoughtful analyis of a set of visualizations of crime statistics.

Understanding Web Operations Culture - the Graph & Data Obsession

by Jesse Robbins | @jesserobbins | comments: 8

We’re quite addicted to data pr0n here at Flickr. We’ve got graphs for pretty much everything, and add graphs all of the time.

-John Allspaw, Operations Engineering Manager at Flickr & author of The Art of Capacity Planning

One of the most interesting parts of running a large website is watching the effects of unrelated events affecting user traffic in aggregate. Web traffic is something that companies typically keep very secret, and often the only time engineers can talk about it is late at night, at a bar, and very much off the record.

There are many good reasons for keeping this kind of information confidential, particularly for publicly traded companies with complicated disclosure requirements. There are also downsides, the biggest being that is difficult for peers to learn from each other and compare notes.

John Allspaw recently created a WebOps Visualizations group on Flickr for sharing these kinds of graphs with the confidential information removed. Here’s an example of a traffic drop seen both by Flickr & by Last.FM that coincided with President Obama’s inauguration.

Similar traffic drop on Last.FM seen on the right

Google saw a similar drop as well

Was it because everybody went to Twitter?

Besides being an interesting story, sharing these kinds of graphs help people build better monitoring tools and processes. As just one example: How should the WebOps team respond to this dip in traffic? Is it an outage? The inaguration was a very well known event and so it’s easy to explain the drop in traffic… what happens when a similar drop in traffic occurs? Should the WebOps team be looking at CNN (or trends in twitter) along with everything else?

How do you tell when that unexpected 10% drop in traffic is really just people with something more important to do than browse your site?

(Note: Updated since original posting to add Google & Twitter graphs and annotations, and to switch the Last.FM graphic with an annotated one after I got permission.)

Two new open source projects at Velocity

by Jesse Robbins | @jesserobbins | comments: 3

At Velocity next week there will be two significant open source projects debuting. The first is the Jiffy: Open Source Performance Measurement and Instrumentation tool created by Scott Ruthfield and his team at Whitepages.com.

Most tools for measuring web performance come in two flavors:

• Developer-installed tools (Firebug, Fiddler, etc.) that allow individuals to closely trace single sessions


• Third-party performance monitoring systems (Gomez, Keynote, etc.) that will hit your site occasionally and report back component-level metrics (for a fee)

Neither of these tools give you real-world information on what’s actually happening with your clients—how long are pages really taking to load, what’s the real cost of client-side execution, and what’s the impact of your loading or dependency chain. This is even more important when you don’t host all of your own assets, such as when you load ads or JavaScript from third parties, for example, and you need to monitor their performance.

Thus we built Jiffy—an end-to-end system for instrumenting your web pages, capturing client-side timings for any event that you determine, and storing and reporting on those timings. You run Jiffy yourself, so you aren’t dependent on the performance characteristics, inflexibility, or costs of third-party hosted services.

The second is project is EUCALYPTUS, the Elastic Utility Computing Architecture for Linking Your Programs To Useful Systems, presented by Rich Wolski from UCSB. This project has already started getting attention. (Many thanks to Surj Patel of Structure08/GigaOM for connecting us!)

Eucalyptus is an open-source software infrastructure for implementing "cloud computing" on clusters. The current interface to EUCALYPTUS is compatible with Amazon's EC2 interface, but the infrastructure is designed to support multiple client-side interfaces. EUCALYPTUS is implemented using commonly-available Linux tools and basic Web-service technologies making it easy to install and maintain.

The talk will focus on the design, the implementation tradeoffs we have identified in implementing Eucalyptus as an exploratory tool, and the ways in which we have chosen to address these tradeoffs in the first version of the software.