Running a rails performance test I get unsupported for memory and objects in the output. For ruby 1.9x one can install a gcdata patch. However, I can't figure out how to install that for ruby 2.0.
When I run:
bundle exec rake test:benchmark RAILS_ENV=test
I get:
BrowsingTest#test_homepage (247 ms warmup)
wall_time: 3 ms
memory: unsupported
objects: unsupported
gc_runs: 0
gc_time: 0 ms
= 1.42 sFinished tests in 1.500688s, 0.6664 tests/s, 0.0000 assertions/s.
1 tests, 0 assertions, 0 failures, 0 errors, 0 skips
I have Rails 3.2.21 and Ruby 2.0:
ruby 2.0.0p598 (2014-11-13 revision 48408) [x86_64-darwin14.1.0]
The gcdata patch is only available for the latest version of 1.9.3. There is no gcdata patch for Ruby >= 2.0.0. In my opinion, you have two options for this issue:
Keep a branch of your application running a patched version of Rails 1.9.3, and run the tests there. The downside will be that the results may not be 100% accurate and if you will use Ruby 2 syntax your branch will break.
Find another way to test the memory usage and created objects, or don't use the option at all with your new application. The good news is that Ruby 2+ now handles Garbage Collection better and you should not run out of memory (unless you are interested to get a number comparison for your app).