ActiveRecord::ConnectionTimeoutError happening sporadically

Question

Whenever I have an application using ActiveRecord I get this ConnectionTimeoutError - but always after a certain unknown period of time

ActiveRecord::ConnectionTimeoutError (could not obtain a database connection within 5 seconds.  The max pool size is currently 30; consider increasing it.):

It was previously set to 5, we have already increased it, and there is no way it can be using 30 connections at the same time. The only thing we use ActiveRecord for is our session store.

Our database.yml file looks like:

development:
  adapter: sqlite3
  database: db/development.sqlite3
  pool: 30
  timeout: 5000

(Test and production settings are the same)

---

I have been googling this occurrence, and just came across this posting:

https://groups.google.com/forum/#!msg/copenhagen-ruby-user-group/GEHgi_WudmM/gnCiwWqmVfMJ

Which mentions that ActiveRecord does not check a connection back into the pool once it is done with it?? Is that true? Do I need to manually manage the connections?

I appreciate any advice!!

edit I should probably mention I am running Rails 3.1.3

Answer 1

Rails has a middleware called ActiveRecord::ConnectionAdapters::ConnectionManagement which clears active connections every request so they do not stick around. Check your middleware to make sure you have this (which is there by default), run "rake middleware". You should not have to manage the connections manually to answer your last question.

Run this in your console

   ActiveRecord::Base.clear_active_connections!