Oct '06
Profiling Rails Unittests
by Frank Spychalski filed under Rails, Ruby

Thanks to a hint by Chris Mear on the Ruby on Rails Mailinglist I had an idea how to add profiling my unittests. It’s a simple 3 step process and adds just 5 lines of code to your unittests:

Step 1:

require 'profiler'

Step 2:

 def setup
  # ...
  # your normal setup code
  # ...

Step 2:

 def teardown
  f=File::new("#{RAILS_ROOT}/log/profiler.#{name() + ' ' +
    '%Y-%m-%d %H:%M')}.log", 'w')
  # ...
  # your normal teardown code
  # ...

As you probably guessed from the code, this will log the profiling results into a file for each test. But beware: this is VERY SLOW! The tests I was profiling took 9s without profiling and 1267s with profiling… But slow profiling still beats no profiling :-)

If you are looking for memory profiling, there is a nice article by Scott Laird on Memory leak profiling with Rails.

Any comments? Or questions? Just leave a Reply: