So your application’s memory usage increase dramatically and you don’t know why.
We’ve all been there.
This guide assumes you’re using Rails 4, Heroku and Papertrail to save logs. Honestly all you need are the log files anyways.
Install the Oink gem for your Rails application.
gem'oink'In both, production.rb and development.rb, make sure you have the Oink middleware
set up to save memory usage information directly to our logs.
config.middleware.use(Oink::Middleware,:logger=>Hodel3000CompliantLogger.new(STDOUT))That Hodel3000CompliantLogger bit is very important! Oink can only read lines formatted using that logger format.
Let your app do it’s thing for a day or two - then download the huge logs you have amassed. This will give you real insight to what pages your users are hitting and how memory is moving around.
Download your logs from Papertrail, and massage it into something Oink can understand by removing the unnecessary log lines.
$ cat papertrail.tsv | cut -f 10- | grep 'rails\['> production-oink.log
Now feed that file into Oink and you’re all set.
$ oink --threshold=0 production-oink.log
Example output:
sergiotapia at Sergios-iMac in ~/Work/App
$ oink --threshold=0 production-oink.log
---- MEMORY THRESHOLD ----
THRESHOLD: 0 MB
-- SUMMARY --
Worst Requests:
1. May 03 03:51:10, 356004 KB, users#show
2. May 03 03:16:07, 311312 KB, users#show
3. May 03 18:48:34, 304216 KB, users#show
4. May 03 08:17:27, 292592 KB, users#show
5. May 03 02:49:16, 288608 KB, users#show
6. May 03 06:43:21, 236604 KB, users#show
7. May 03 03:08:15, 235912 KB, users#show
8. May 03 00:02:33, 233092 KB, users#show
9. May 03 23:43:51, 232632 KB, users#show
10. May 03 22:01:59, 231676 KB, users#show
