Module: Litescheduler

Defined in:
lib/litestack/litescheduler.rb

Overview

frozen_stringe_literal: true

Class Method Summary collapse

Class Method Details

.backend ⇒ Object

cache the scheduler we are running in it is an error to change the scheduler for a process or for a child forked from that process



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# File 'lib/litestack/litescheduler.rb', line 7

def self.backend
  @backend ||= if Fiber.scheduler
    :fiber
  elsif defined? Polyphony
    :polyphony
  elsif defined? Iodine
    :iodine
  else
    :threaded
  end
end

.current ⇒ Object 



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# File 'lib/litestack/litescheduler.rb', line 39

def self.current
  if fiber_backed?
    Fiber.current
  else
    Thread.current
  end
end

.max_contexts ⇒ Object 



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# File 'lib/litestack/litescheduler.rb', line 74

def self.max_contexts
  return 50 if fiber_backed?
  5
end

.mutex ⇒ Object

mutex initialization



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# File 'lib/litestack/litescheduler.rb', line 80

def self.mutex
  # a single mutex per process (is that ok?)
  @@mutex ||= Mutex.new
end

.spawn(&block) ⇒ Object

spawn a new execution context



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# File 'lib/litestack/litescheduler.rb', line 20

def self.spawn(&block)
  if backend == :fiber
    Fiber.schedule(&block)
  elsif backend == :polyphony
    spin(&block)
  elsif (backend == :threaded) || (backend == :iodine)
    Thread.new(&block)
  end
  # we should never reach here
end

.storage ⇒ Object 



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# File 'lib/litestack/litescheduler.rb', line 31

def self.storage
  if fiber_backed?
    Fiber.current.storage
  else
    Thread.current
  end
end

.switch ⇒ Object

switch the execution context to allow others to run



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# File 'lib/litestack/litescheduler.rb', line 48

def self.switch
  if backend == :fiber
    Fiber.scheduler.yield
    true
  elsif backend == :polyphony
    Fiber.current.schedule
    Thread.current.switch_fiber
    true
  else
    # Thread.pass
    false
  end
end

.synchronize(fiber_sync = false, &block) ⇒ Object

bold assumption, we will only synchronize threaded code! If some code explicitly wants to synchronize a fiber they must send (true) as a parameter to this method else it is a no-op for fibers



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# File 'lib/litestack/litescheduler.rb', line 66

def self.synchronize(fiber_sync = false, &block)
  if fiber_backed?
    yield # do nothing, just run the block as is
  else
    mutex.synchronize(&block)
  end
end