Find a list of slow rspec tests

Question

How can I find a list of the slowest rspec tests? I want to refactor those to run faster. I tried looking for gems but can't find any. I was thinking of putting something in

Rspec.before(:each)

and

Rspec.after(:each)

blocks to generate this list. But I don't know how to access the name of the spec.

score 74 · Accepted Answer · answered Jun 07 '12 at 18:11

74

That's actually built right in to the rspec command. Just use the -p or --profile flag while you're running all your rspec tests.

answered Jun 07 '12 at 18:11

MrDanA

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8

As a note, the profile won't print if your specs are failing. – Gavin Miller Jun 26 '12 at 19:03

score 15 · Answer 2 · answered Jun 07 '12 at 18:17

15

As MrDan says, the --profile flag. You can also make a .rspec file in the root of your project, so that you get the timing information all the time, like this:

$ cat .rspec 
--colour
--profile
--format nested
--backtrace

You can also speed up all your tests generally by turning off garbage collection, like this:

# turn off garbage collection when running tests, place this in spec_helper.rb
RSpec.configure do |config|
  config.before(:all) do
     DeferredGarbageCollection.start
  end

  config.after(:all) do
     DeferredGarbageCollection.reconsider
  end
end

answered Jun 07 '12 at 18:17

Rob

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Thanks, but I get "uninitialized constant DeferredGarbageCollection" – Ibrahim Muhammad Jun 07 '12 at 19:05
https://makandracards.com/makandra/950-speed-up-rspec-by-deferring-garbage-collection – michelpm Jul 10 '12 at 19:52
Deferring GC is a pretty interesting idea. @rob do you see any drawbacks at doing this? – marcgg Feb 07 '13 at 16:10
2

Not really. I suppose you might run out of memory before you finish all the tests, but we have 99% coverage and 5000+ tests, and we don't run out. – Rob Feb 23 '13 at 14:57

Find a list of slow rspec tests

2 Answers2