Custodian

Custodian is a lightweight resource monitor that makes it really easy and really awesome to sample metrics.

Usage

Server

Start Custodian and configure it to expose metrics on port 5100:

$ custodian --port=5100

Samplers

Custodian aggregates metrics from samplers, and ships with a whole bunch of them for popular figures like CPU, RAM and disk usage. That's interesting and all, but custom samplers are all the rage:

class RegisteredUsers < Custodian::Samplers::Sampler
  describe "Registered users"

  def self.sample
    Users.count
  end
end

Samplers are just Ruby classes that inherit from Custodian::Samplers::Sampler and implement a sample method, and you can load your own with the --samplers option.

$ custodian --samplers=~/.samplers

Clients

Unless you're crazy about JSON, you'll want to consume Custodian's API with a client. There are no clients for Custodian yet, but you should totally make one.

I love you

Johannes Gorset made this. You should tweet me if you can't get it to work. In fact, you should tweet me anyway.