Comic Relief, @garethr, @LordCope, and CloudFoundry at QConLondon 2013

Posted on by Matthew Skelton (@matthewskelton)

I attended QConLondon 2013 last week; what I took from the first four sessions in the Building for Clouds track was: cloud API and infrastructure automation tools have now solved most of the ‘easy’ cloud problems, but harder challenges (such as automating clusters) remain. The sessions were from Tim Savage (@timjsavage) and Zenon Hannick (@zenonhannick) on Comic Relief’s unique challenges with performance testing, Gareth Rushgrove (@garethr) on how to avoid PaaS lock-in, Stephen Nelson-Smith (@LordCope) on how to use Chef to give you ‘optionality’ with different cloud vendors, and Andrew Crump (@acrmp) and Chris Hedley (@ChristHedley) on the CloudFoundry cloud platform.

Continue reading Comic Relief, @garethr, @LordCope, and CloudFoundry at QConLondon 2013

What Makes an Effective Build and Deployment Radiator Screen?

Posted on by Matthew Skelton (@matthewskelton)

Build screens (or build monitors, or information radiators) are an important tool in helping to achieve Continuous Integration and in trapping errors early. When the number of build jobs becomes large, it can be tempting to hide ‘successful’ jobs to save space, but we found this to cause problems. I realised that people need to know the context for the red jobs if they are to take prompt action to fix failing builds, so it’s important to represent the full state of all builds by showing green jobs too.

Continue reading What Makes an Effective Build and Deployment Radiator Screen?

How HTTPbis changes HTTP caching, and why CDNs are not always the answer

Posted on by Matthew Skelton (@matthewskelton)

HTTP caching is a key part of what makes the web usable, and draft standards like HTTPbis add further refinements to the existing HTTP/1.1 caching features. At WebPerfDays 2012, Mark Nottingham (@mnot) and Josh Bixby (@joshuabixby) gave some useful tips on how we can tune our web applications to take advantage of the existing and forthcoming HTTP cache features.

Continue reading How HTTPbis changes HTTP caching, and why CDNs are not always the answer

2012 in review – blog.matthewskelton.net

Posted on by Matthew Skelton (@matthewskelton)

The WordPress.com stats helper monkeys prepared a 2012 annual report for this blog.

Here’s an excerpt:

600 people reached the top of Mt. Everest in 2012. This blog got about 10,000 views in 2012. If every person who reached the top of Mt. Everest viewed this blog, it would have taken 17 years to get that many views.

Click here to see the complete report.

Festive Graphite Line Art for the Masses

Posted on by Matthew Skelton (@matthewskelton)

You have an installation of Graphite, a desire to learn more Ruby, and some festive spirit – what emerges?

An xmas tree drawn using proper metrics via the Ruby graphite gem, of course!

Xmas tree plotted using Graphite

The magic happens with the Graphite::Logger class, because we can log metrics at specific points in time:

logger.log(when,{"Branches1" => 3})

I calculated the points to plot on paper, and found decent Graphite rendering settings by experimentation:

Planning the Graphite Xmas tree

The code is on Github here: https://github.com/matthewskelton/GraphiteGreetings – fork away!

require 'Graphite'
require 'Logger'
# Change these as needed for your environment
server = "my.graphite.server.url"
log = Logger.new(STDOUT)
prefix = "Test.Me.XmasTree."
# Create the logger to send stats to Graphite with specific timings
logger = Graphite::Logger.new(server,log)
# Define the offsets
#
# Use Now as a starting point,
# or set a specific time e.g. Time.utc(2012,12,22,19,10,30)
# We need a 20-minute window to plot
t = Time.now
t0 = Time.at(t.to_i - (20 * 60)) # 20 mins ago
t1 = Time.at(t0.to_i + (60 * 1)) # Left base of tree
t2 = Time.at(t0.to_i + (60 * 3)) # Lower tinsel2
# etc.
# Inject the stats - the order is determined by the default Graphite colours
logger.log(t21,{prefix + "Tinsel1" => 3})
logger.log(t18,{prefix + "Tinsel1" => 6})
# etc.
view raw gistfile1.rb hosted with ❤ by GitHub

I’d love to hear or see any suggestions for improvements to the script. Candles? Snowflakes? Reindeer?! Also, as my Ruby-fu is limited, if there are better ways of interacting with Graphite, I’d love the hear about them (I tried and failed to get activesupport to work on my machine, for example).