cfis : How to Profile Your Rails Application

Comment on How to Profile Your Rails Application by Gary Murakami

Thu, 12 Jul 2007 14:25:54 -0600

You wrote, “Obviously for real testing you’ll need to make many requests, …” This is my current wish. With many requests, it appears that mongrel spawns a new thread for each request, resulting in output from ruby-prof for each request/thread and loss of aggregate behavior over many requests. Any hints and remedies would be welcome, e.g., is there a way to make mongrel use the same thread?

Comment on How to Profile Your Rails Application by Tim

Thu, 12 Jul 2007 14:32:25 -0600

Um.. where is the rails plugin?

ruby-prof/rails_plugin doesn’t seem to exist

Comment on How to Profile Your Rails Application by Charlie

Thu, 12 Jul 2007 17:55:50 -0600

Tim,

It should be installed under:

gems\ruby-prof-0.5.0\lib\ruby-prof\rails_plugin

I think maybe I’ll change it to be directly under the top ruby-prof directory in a future release.

Comment on How to Profile Your Rails Application by Charlie

Thu, 12 Jul 2007 18:01:36 -0600

Hi Gary,

Yeah, ruby-prof doesn’t maintain aggregate information. And I’m not sure how mongrel does threading, haven’t ever checked.

I’m not sure though how useful it would be though for ruby-prof to aggregate data. I think profiling one request is fine for getting a feel for timings. Usually what I do is tail the rails log file, and then do one request at a time and scan the results to make sure they are consistent.

Now, to validate that your changes have improved performance, you definitely want to gather average times and standard deviations before and after any changes. And to do that, you should run a fair number of tests (and if I remember my statistics correctly, there are methodologies that tell you just how many tests that is).

Hope this helps a bit - good luck!

Trackback from cfis: Making Rails Go Vroom on How to Profile Your Rails Application

Wed, 18 Jul 2007 11:16:52 -0600

Last week I demonstrated how to profile a Rails application using ruby-prof. The post was driven by our desire to improve MapBuzz's map rendering speed. Our nightly log analysis showed that rendering speed had significantly degraded over the last ...

Comment on How to Profile Your Rails Application by Tim

Thu, 19 Jul 2007 13:21:18 -0600

I don’t think the plugin was included in 0.5.1

Comment on How to Profile Your Rails Application by Charlie

Thu, 19 Jul 2007 14:11:26 -0600

Hi Tim,

Wow - you’re right - how embarrassing. I just uploaded 0.5.2 which fixes the issue - hopefully it will be showing up soon on RubyForge.

Trackback from blogwi.se: How-to Profile your Ruby (on Rails) Application on How to Profile Your Rails Application

Sun, 22 Jul 2007 11:26:29 -0600

Our current project is by far not yet in the state where we can and want to profile it’s overall performance, but considering its current pace, we might be there in a couple weeks and therefore this post also is meant to be a little reminde...

Trackback from Quicklinks: links for 2007-07-27 on How to Profile Your Rails Application

Fri, 27 Jul 2007 05:17:14 -0600

How to Profile Your Rails Application (tags: Rails performance development) Making Rails Go Vroom (tags: Rails development performance)...

Comment on How to Profile Your Rails Application by Sean

Mon, 30 Jul 2007 08:39:21 -0600

Following the above directions, I’m trying to profile some actions that are notoriously slow on our site, but I can’t access them because I keep getting LoadError’s. Any clue what might cause this?

Trackback from Scott's Place: links for 2007-07-31 on How to Profile Your Rails Application

Mon, 30 Jul 2007 18:22:08 -0600

Making Rails go Vroom Practical walkthrough of optimising a Rails app using profiling reports (tags: activerecord articles code deployment dev development geek howto optimisation performance rails reference ruby rubyonrails software speed tips tut...

Comment on How to Profile Your Rails Application by Location of Ruby Gem dir on Mac OS X

Tue, 18 Mar 2008 14:49:38 -0600

After amany Google searches, I eventually found the location of the Gems dir on OS X 10.5 Leopard. It’s /Library/Ruby/Gems/1.8/gems

So to copy the plugin, you do:

cp -r /Library/Ruby/Gems/1.8/gems/ruby-prof-0.6.0/rails_plugin /path/to/railsapp/vendor/plugins/

Comment on How to Profile Your Rails Application by Roger

Wed, 19 Mar 2008 12:03:18 -0600

Note also the importance of profiling the whole app – so start the profiling within mongrel or somewhere that is global, so you can see if the asset manager is eating your lunch or what is. Good luck!

Comment on How to Profile Your Rails Application by Roger

Wed, 19 Mar 2008 12:07:09 -0600

Note that if you google for it, kcachegrind appears available for mac os and for windows, too. Thanks!

Comment on How to Profile Your Rails Application by Neel

Thu, 26 Jun 2008 05:59:51 -0600

While I a m having many request at a time I can see only one Thread ID information on request.html, How to view information related to multiple requests.