Performance problem on 4.2.3-4.2.4 - only development env


this is more an advice than a question.

Just upgrade my rails app from 4.2.0 to 4.2.3 (and finally 4.2.4) to get rid of a bug and I realized that some views with forms now takes 2x time to render.

Using ruby-prof I’ve found that the performance problem can be avoided commenting the “web-console” gem in Gemfile.

I’m not an expert reading ruby-prof reports but the problem appears to be in


that is called after


It seems that I18n::MissingTranslation::Base#to_exception is not called on rails 4.2.0 because I have not found any reference to that method in the report.

On Rails 4.2.4 without using web-console the view render is slightly faster than 4.2.0, and the send of I18n::MissingTranslation::Base#to_exception has no measurable cost because Exception#set_backtrace_with_binding_of_caller is not called.

I can send the ruby-prof reports upon request. And this is with ruby 2.2.2p95 if it matters.


Sebastian Calvo