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```````pony linenums="1"
use @pony_schedulers[U32]()
use @pony_active_schedulers[U32]()
use @pony_min_schedulers[U32]()
use @pony_scheduler_yield[Bool]()
use @pony_scheduler_index[I32]()

primitive Scheduler
  """
  Provides functions that expose information about runtime schedulers.
  """

  fun schedulers(auth: SchedulerInfoAuth): U32 =>
    """
    Returns the maximum number of schedulers available to run actors.
    """
    @pony_schedulers()

  fun active_schedulers(auth: SchedulerInfoAuth): U32 =>
    """
    Returns the number of schedulers currently available to run actors.
    """
    @pony_active_schedulers()

  fun minimum_schedulers(auth: SchedulerInfoAuth): U32 =>
    """
    Returns the minimum number of schedulers. The active number of schedulers is
    guaranteed to never drop below this number.
    """
    @pony_min_schedulers()

  fun suspended_schedulers(auth: SchedulerInfoAuth): U32 =>
    """
    Returns the number of schedulers that have suspended and are not
    available to run actors. A scheduler suspends when there isn't enough
    work to keep all of the schedulers busy.
    """
    @pony_schedulers() - @pony_active_schedulers()

  fun scaling_is_active(auth: SchedulerInfoAuth): Bool =>
    """
    Returns true if scheduler scaling is on and the number of active schedulers
    can change with load while the program is running.
    """
    schedulers(auth) > minimum_schedulers(auth)

  fun will_yield_cpu(auth: SchedulerInfoAuth): Bool =>
    """
    Returns true if schedulers without work will yield the CPU allowing other
    processes to have access.
    """
    @pony_scheduler_yield()

  fun scheduler_index(auth: SchedulerInfoAuth): I32 =>
    """
    Returns the index of the current scheduler thread
    """
    @pony_scheduler_index()

```````