-- Hoogle documentation, generated by Haddock
-- See Hoogle, http://www.haskell.org/hoogle/


-- | Task Framework for The Cloud Haskell Application Platform
--   
--   The Task Framework intends to provide tools for task management, work
--   scheduling and distributed task coordination. These capabilities build
--   on the Async Framework as well as other tools and libraries. The
--   framework is currently a work in progress. The current release
--   includes a simple bounded blocking queue implementation only, as an
--   example of the kind of capability and API that we intend to produce.
@package distributed-process-task
@version 0.1.0


-- | A simple bounded (size) task queue, which accepts requests and blocks
--   the sender until they're completed. The size limit is applied to the
--   number of concurrent tasks that are allowed to execute - if the limit
--   is 3, then the first three tasks will be executed immediately, but
--   further tasks will then be queued (internally) until one or more tasks
--   completes and the number of active/running tasks falls within the
--   concurrency limit.
--   
--   Note that the process calling <a>executeTask</a> will be blocked for
--   _at least_ the duration of the task itself, regardless of whether or
--   not the queue has reached its concurrency limit. This provides a
--   simple means to prevent work from being submitted faster than the
--   server can handle, at the expense of flexible scheduling.
module Control.Distributed.Process.Task.Queue.BlockingQueue
data BlockingQueue a

-- | Limit for the number of concurrent tasks.
type SizeLimit = Int
data BlockingQueueStats
BlockingQueueStats :: Int -> Int -> Int -> BlockingQueueStats
maxJobs :: BlockingQueueStats -> Int
activeJobs :: BlockingQueueStats -> Int
queuedJobs :: BlockingQueueStats -> Int

-- | Start a queue with an upper bound on the # of concurrent tasks.
start :: Serializable a => Process (InitResult (BlockingQueue a)) -> Process ()

-- | Define a pool of a given size.
pool :: Serializable a => SizeLimit -> Process (InitResult (BlockingQueue a))

-- | Enqueue a task in the pool and block until it is complete.
executeTask :: (Addressable s, Serializable a) => s -> Closure (Process a) -> Process (Either ExitReason a)

-- | Fetch statistics for a queue.
stats :: Addressable s => s -> Process (Maybe BlockingQueueStats)
instance Typeable GetStats
instance Typeable BlockingQueueStats
instance Typeable BlockingQueue
instance Generic GetStats
instance Generic BlockingQueueStats
instance Datatype D1GetStats
instance Constructor C1_0GetStats
instance Datatype D1BlockingQueueStats
instance Constructor C1_0BlockingQueueStats
instance Selector S1_0_0BlockingQueueStats
instance Selector S1_0_1BlockingQueueStats
instance Selector S1_0_2BlockingQueueStats
instance Binary BlockingQueueStats
instance Binary GetStats


-- | The <i>Task Framework</i> intends to provide tools for task
--   management, work scheduling and distributed task coordination. These
--   capabilities build on the <i>Execution Framework</i> as well as other
--   tools and libraries. The framework is currently a work in progress.
--   The current release includes a simple bounded blocking queue
--   implementation only, as an example of the kind of capability and API
--   that we intend to produce.
--   
--   The <i>Task Framework</i> will be broken down by the task scheduling
--   and management algorithms it provides, e.g., at a low level providing
--   work queues, worker pools and the like, whilst at a high level
--   allowing the user to choose between work stealing, sharing,
--   distributed coordination, user defined sensor based bounds/limits and
--   so on.
module Control.Distributed.Process.Task