How do you do performance testing in Ruby webapps?

Question

I've been looking at ways people test their apps in order decide where to do caching or apply some extra engineering effort, and so far httperf and a simple sesslog have been quite helpful.

What tools and tricks did you apply on your projects?

Answer 1

I use httperf for a high level view of performance.

Rails has a performance script built in, that uses the ruby-prof gem to analyse calls deep within the Rails stack. There is an awesome Railscast on Request Profiling using this technique.

NewRelic have some seriously cool analysis tools that give near real-time data. They just made it a "Lite" version available for free.

Answer 2

I use jmeter for session-based testing - it allows very fine-grained control over pages you want to hit, parameters to inject, loops to go through, etc. It's great for simulating how many real users your site can handle, rather than just performance testing a set of static urls. You can distribute tests over multiple machines quite easily by loading up the jmeter-server on computers with publicly accessible IP's. I have found some limitations in the number of users/threads any one machine can throw at a server at once (it depends on the test), but jmeter has helped my team improve our apps capacity for users to 6x.

It doesn't have any fancy graphing -- I actually use my own in-house graphing with gruff that can do performance analysis on request time for certain pages and actions.

Answer 3

I'm evaluating a new opensource web page instrumentation and measurement suite called Jiffy. It's not particularly for ruby, it works for all kind of webapps

There's also a Jiffy Firebug Extension for rendering the metrics inside the browser.

Answer 4

A colleague of mine has also posted some interesting thoughts on this.

Answer 5

I also suggest you look at Browser Mob for load testing.