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Performance tools are a great help for testing your web application deployment setup. They not only let you judge how the performance of the application is but also catch errors. Nobody wants a web application which starts to spit out errors when put under load or worse, randomly!

HTTPERF is a gift from HP which is my favourite tool at the moment.

An example httperf usage is:

  httperf --num-conns=800 --rate=80 --timeout=5 --server=google.com --port=80 --uri=/

This hits the google homepage with 80 requests per second for 800 requests in total. This test will run for circa 10 seconds.

Results are as follows:

Total: connections 800 requests 800 replies 800 test-duration 10.252 s

Connection rate: 78.0 conn/s (12.8 ms/conn, <=25 concurrent connections)
Connection time [ms]: min 140.1 avg 237.1 max 771.7 median 240.5 stddev 40.5
Connection time [ms]: connect 111.2
Connection length [replies/conn]: 1.000

Request rate: 78.0 req/s (12.8 ms/req)
Request size [B]: 63.0

Reply rate [replies/s]: min 76.2 avg 77.9 max 79.6 stddev 2.4 (2 samples)
Reply time [ms]: response 125.9 transfer 0.0
Reply size [B]: header 280.0 content 219.0 footer 0.0 (total 499.0)
Reply status: 1xx=0 2xx=0 3xx=800 4xx=0 5xx=0

CPU time [s]: user 0.51 system 9.64 (user 5.0% system 94.1% total 99.0%)
Net I/O: 42.8 KB/s (0.4*10^6 bps)

Errors: total 0 client-timo 0 socket-timo 0 connrefused 0 connreset 0
Errors: fd-unavail 0 addrunavail 0 ftab-full 0 other 0

This line below is important:

Reply rate [replies/s]: min 76.2 avg 77.9 max 79.6 stddev 2.4 (2 samples)

It tells us that the avg requests per second is 77.9. There is a low standard deviation, which is good. If you have a high stddev you should be worried. Lastly, it has calculated this using 2 samples. You can increase the number of samples by increasing the num-conns, which will give you a more reliable dataset.

Watch out for the errors:

Errors: total 0 client-timo 0 socket-timo 0 connrefused 0 connreset 0
Errors: fd-unavail 0 addrunavail 0 ftab-full 0 other 0

Looking good, google is performing well on the error front. Obviously google.com handles more than 80 req/s! Now go away and performance test some of your sites!

There is some valuable further watching to be had. Episodes 15 and 16 mention httperf.

I have been keen to get my hands dirty with ExtJS, so jumped at the chance to make a christmas card list application which can print the list to labels; to stick on envelopes.

I have finally become mature enough to have a christmas card list along with my girlfriend, which is useful for keeping track of friends both in Trondheim and the United Kingdom.

To get it up and running on heroku it is pretty swift –

  git clone git://github.com/pyrat/christmas-card-labels.git
  cd christmas-card-labels
  sudo gem install heroku
  heroku create
  git push heroku master
  heroku rake db:migrate

You are now good to go, you may need to tweak the css (labels.css) to match your specific labels which can be a painful experience.

Default username / password is god / jul which is norwegian for merry christmas!

There is a demo version online

Maybe not that ‘wicked’ but was fun running with the Reindeer last weekend. After the film was taken they got a bit angry and stopped running. I then retreated.