Sidekiq strategy to support a granular queue control – limiting, pausing, blocking, querying.
Add this line to your application's Gemfile:
redis 2.6 or newer
Specify limits which you want to place on queues inside sidekiq.yml:
:limits: queue_name1: 5 queue_name2: 10
Or set it dynamically in your code:
Sidekiq::Queue['queue_name1'].limit = 5
Sidekiq::Queue['queue_name2'].limit = 10
In these examples, tasks for the
queue_name1 will be run by at most 5
workers at the same time and the
queue_name2 will have no more than 10
Ability to set limits dynamically allows you to resize worker distribution among queues any time you want.
Busy workers by queue
You can see how many workers currently handling a queue:
Sidekiq::Queue['name'].busy # number of busy workers
You can also pause your queues temporarely. Upon continuing their limits will be preserved.
Sidekiq::Queue['name'].pause # prevents workers from running tasks from this queue Sidekiq::Queue['name'].paused? # => true Sidekiq::Queue['name'].unpause # allows workers to use the queue
Blocking queue mode
If you use strict queue ordering (it will be used if you don't specify queue weights) then you can set blocking status for queues. It means if a blocking queue task is executing then no new task from lesser priority queues will be ran. Eg,
:queues: - a - b - c :blocking: - b
In this case when a task for
b queue is ran no new task from
will be started.
You can also enable and disable blocking mode for queues on the fly:
Sidekiq::Queue['name'].block Sidekiq::Queue['name'].blocking? # => true Sidekiq::Queue['name'].unblock
Advanced blocking queues
You can also block on array of queues. It means when any of them is running only queues higher and queues from their blocking group can run. It will be easier to understand with an example:
:queues: - a - b - c - d :blocking: - [b, c]
In this case tasks from
d will be blocked when a task from queue
c is executed.
You can dynamically set exceptions for queue blocking:
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