Specifying number of queues?

[araishikeiwai]

Hi,

I specified a job with queue 'my-job:5::5', but when I run Backburner.work via rake task (somehow I can't call rake backburner:work, it shows Don't know how to build task 'environment' (see --tasks) even require 'backburner/tasks' is included already), sometimes it shows this:

INFO -- : Working 2 queues: [ my-default-queue.my-job:[5, nil, 5], my-default-queue.backburner-jobs:[nil, nil, nil] ]

And sometimes it shows this (duplication):

INFO -- : Working 4 queues: [ my-default-queue.my-job:[5, nil, 5], my-default-queue.backburner-jobs:[nil, nil, nil], my-default-queue.my-job:[5, nil, 5], my-default-queue.backburner-jobs:[nil, nil, nil] ]

And if I run two instances of Backburner.work, I can't predict how many queues are going to be run.

Is there a way to specify the number of queues run by Backburner.work?