› Async › Source › Async › Loop

module Loop

Definitions

def self.quantized(interval: 60, &block)

  • public

Execute a block repeatedly at quantized (time-aligned) intervals.

The alignment is computed modulo the current clock time in seconds. For example, with interval: 60, executions will occur at 00:00, 01:00, 02:00, etc., regardless of when the loop is started. With interval: 300 (5 minutes), executions align to 00:00, 00:05, 00:10, etc.

This is particularly useful for tasks that should run at predictable wall-clock times, such as metrics collection, periodic cleanup, or scheduled jobs that need to align across multiple processes.

If an error occurs during block execution, it is logged and the loop continues.

Example: Run every minute at :00 seconds:

 
Async::Loop.quantized(interval: 60) do
	puts "Current time: #{Time.now}"
end

Example: Run every 5 minutes aligned to the hour:

 
Async::Loop.quantized(interval: 300) do
	collect_metrics
end

Signature
parameter　interval　Numeric

The interval in seconds. Executions will align to multiples of this interval based on the current time.

public

Since Async v2.37.

Implementation

 
def self.quantized(interval: 60, &block)
	while true
		# Compute the wait time to the next interval:
		wait = interval - (Time.now.to_f % interval)
		if wait.positive?
			# Sleep until the next interval boundary:
			sleep(wait)
		end
		
		begin
			yield
		rescue => error
			Console.error(self, "Loop error:", error)
		end
	end
end

def self.periodic(interval: 60, &block)

  • public

Execute a block repeatedly with a fixed delay between executions.

Unlike Async::Loop.quantized, this method waits for the specified interval after each execution completes. This means the actual time between the start of successive executions will be interval + execution_time.

If an error occurs during block execution, it is logged and the loop continues.

Example: Run every 5 seconds (plus execution time):

 
Async::Loop.periodic(interval: 5) do
	process_queue
end

Signature
parameter　interval　Numeric

The delay in seconds between executions.

public

Since Async v2.37.

Implementation

 
def self.periodic(interval: 60, &block)
	while true
		begin
			yield
		rescue => error
			Console.error(self, "Loop error:", error)
		end
		
		sleep(interval)
	end
end

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