delayed job - RES keep growing

I have some tasks which needs to rub in background so i was planning to use delayedjob gem but before put in development, i wanted to rub simple TEST to see RES consumption.

Simple Helper with no code

module TestjobHelper
  def self.imageprocess(gb)
    gb = nil
  end
end

Putting into delay job

TestjobHelper.delay(:queue => 'testjob').imageprocess('gb')

Running Delayed Job queue command

RAILS_ENV=development script/delayed_job -i testjob --queue=testjob start

Above sample program, gives keep growing RES value even if there is nothing to do in delayed job function.

RES Output:

http://ift.tt/1OMrl1F

http://ift.tt/1OMrl1H