`class Pack`

Prefer a backend which is already processing the same class of work.

Definitions

`def initialize(affinity: nil)`

Signature

parameter　affinity　Symbol | Nil: The queue affinity to pack, or the current queue by default.

Implementation

def initialize(affinity: nil)
	@affinity = affinity
end

`def select(backends, queue:, request:)`

Select the backend with the most active work for the affinity.

Signature

parameter　backends　Array(Backend): Eligible backends with available permits.
parameter　queue　Queue: The request queue being scheduled.
parameter　request　Protocol::HTTP::Request: The pending request.
returns　Backend | Nil: The preferred backend.

Implementation

def select(backends, queue:, request:)
	affinity = @affinity || queue.name
	backends.min_by do |backend|
		[-backend.processing_for(affinity), backend.processing, backend.name]
	end
end