-- | -- Module : Simulation.Aivika.Queue.Infinite -- Copyright : Copyright (c) 2009-2013, David Sorokin -- License : BSD3 -- Maintainer : David Sorokin -- Stability : experimental -- Tested with: GHC 7.6.3 -- -- This module defines an infinite queue that can use the specified strategies. -- module Simulation.Aivika.Queue.Infinite (-- * Queue Types FCFSQueue, LCFSQueue, SIROQueue, PriorityQueue, Queue, -- * Creating Queue newFCFSQueue, newLCFSQueue, newSIROQueue, newPriorityQueue, newQueue, -- * Queue Properties and Activities enqueueStoringStrategy, dequeueStrategy, queueNull, queueCount, queueCountStats, enqueueStoreCount, dequeueCount, dequeueExtractCount, enqueueStoreRate, dequeueRate, dequeueExtractRate, queueWaitTime, dequeueWaitTime, queueRate, -- * Dequeuing and Enqueuing dequeue, dequeueWithOutputPriority, tryDequeue, enqueue, enqueueWithStoringPriority, -- * Summary queueSummary, -- * Derived Signals for Properties queueNullChanged, queueNullChanged_, queueCountChanged, queueCountChanged_, enqueueStoreCountChanged, enqueueStoreCountChanged_, dequeueCountChanged, dequeueCountChanged_, dequeueExtractCountChanged, dequeueExtractCountChanged_, queueWaitTimeChanged, queueWaitTimeChanged_, dequeueWaitTimeChanged, dequeueWaitTimeChanged_, queueRateChanged, queueRateChanged_, -- * Basic Signals enqueueStored, dequeueRequested, dequeueExtracted, -- * Overall Signal queueChanged_) where import Data.IORef import Data.Monoid import Control.Monad import Control.Monad.Trans import Simulation.Aivika.Internal.Specs import Simulation.Aivika.Internal.Simulation import Simulation.Aivika.Internal.Dynamics import Simulation.Aivika.Internal.Event import Simulation.Aivika.Internal.Process import Simulation.Aivika.Internal.Signal import Simulation.Aivika.Signal import Simulation.Aivika.Resource import Simulation.Aivika.QueueStrategy import Simulation.Aivika.Statistics import qualified Simulation.Aivika.DoubleLinkedList as DLL import qualified Simulation.Aivika.Vector as V import qualified Simulation.Aivika.PriorityQueue as PQ -- | A type synonym for the ordinary FIFO queue also known as the FCFS -- (First Come - First Serviced) queue. type FCFSQueue a = Queue FCFS DLL.DoubleLinkedList FCFS DLL.DoubleLinkedList a -- | A type synonym for the ordinary LIFO queue also known as the LCFS -- (Last Come - First Serviced) queue. type LCFSQueue a = Queue LCFS DLL.DoubleLinkedList FCFS DLL.DoubleLinkedList a -- | A type synonym for the SIRO (Serviced in Random Order) queue. type SIROQueue a = Queue SIRO V.Vector FCFS DLL.DoubleLinkedList a -- | A type synonym for the queue with static priorities applied when -- storing the elements in the queue. type PriorityQueue a = Queue StaticPriorities PQ.PriorityQueue FCFS DLL.DoubleLinkedList a -- | Represents an infinite queue using the specified strategies for -- internal storing (in memory), @sm@, and dequeueing (output), @so@, where @a@ denotes -- the type of items stored in the queue. Types @qm@ and @qo@ are -- determined automatically and you should not care about them - they -- are dependent types. data Queue sm qm so qo a = Queue { enqueueStoringStrategy :: sm, -- ^ The strategy applied when storing (in memory) items in the queue. dequeueStrategy :: so, -- ^ The strategy applied to the dequeueing (output) processes. queueStore :: qm (QueueItem a), dequeueRes :: Resource so qo, queueCountRef :: IORef Int, queueCountStatsRef :: IORef (TimingStats Int), enqueueStoreCountRef :: IORef Int, dequeueCountRef :: IORef Int, dequeueExtractCountRef :: IORef Int, queueWaitTimeRef :: IORef (SamplingStats Double), dequeueWaitTimeRef :: IORef (SamplingStats Double), enqueueStoredSource :: SignalSource a, dequeueRequestedSource :: SignalSource (), dequeueExtractedSource :: SignalSource a } -- | Stores the item and a time of its enqueuing. data QueueItem a = QueueItem { itemValue :: a, -- ^ Return the item value. itemStoringTime :: Double -- ^ Return the time of storing in the queue. } -- | Create a new infinite FCFS queue. newFCFSQueue :: Event (FCFSQueue a) newFCFSQueue = newQueue FCFS FCFS -- | Create a new infinite LCFS queue. newLCFSQueue :: Event (LCFSQueue a) newLCFSQueue = newQueue LCFS FCFS -- | Create a new infinite SIRO queue. newSIROQueue :: Event (SIROQueue a) newSIROQueue = newQueue SIRO FCFS -- | Create a new infinite priority queue. newPriorityQueue :: Event (PriorityQueue a) newPriorityQueue = newQueue StaticPriorities FCFS -- | Create a new infinite queue with the specified strategies. newQueue :: (QueueStrategy sm qm, QueueStrategy so qo) => sm -- ^ the strategy applied when storing items in the queue -> so -- ^ the strategy applied to the dequeueing (output) processes when the queue is empty -> Event (Queue sm qm so qo a) newQueue sm so = do t <- liftDynamics time i <- liftIO $ newIORef 0 is <- liftIO $ newIORef $ returnTimingStats t 0 cm <- liftIO $ newIORef 0 cr <- liftIO $ newIORef 0 co <- liftIO $ newIORef 0 qm <- liftSimulation $ newStrategyQueue sm ro <- liftSimulation $ newResourceWithMaxCount so 0 Nothing w <- liftIO $ newIORef mempty wo <- liftIO $ newIORef mempty s3 <- liftSimulation newSignalSource s4 <- liftSimulation newSignalSource s5 <- liftSimulation newSignalSource return Queue { enqueueStoringStrategy = sm, dequeueStrategy = so, queueStore = qm, dequeueRes = ro, queueCountRef = i, queueCountStatsRef = is, enqueueStoreCountRef = cm, dequeueCountRef = cr, dequeueExtractCountRef = co, queueWaitTimeRef = w, dequeueWaitTimeRef = wo, enqueueStoredSource = s3, dequeueRequestedSource = s4, dequeueExtractedSource = s5 } -- | Test whether the queue is empty. -- -- See also 'queueNullChanged' and 'queueNullChanged_'. queueNull :: Queue sm qm so qo a -> Event Bool queueNull q = Event $ \p -> do n <- readIORef (queueCountRef q) return (n == 0) -- | Signal when the 'queueNull' property value has changed. queueNullChanged :: Queue sm qm so qo a -> Signal Bool queueNullChanged q = mapSignalM (const $ queueNull q) (queueNullChanged_ q) -- | Signal when the 'queueNull' property value has changed. queueNullChanged_ :: Queue sm qm so qo a -> Signal () queueNullChanged_ = queueCountChanged_ -- | Return the current queue size. -- -- See also 'queueCountStats', 'queueCountChanged' and 'queueCountChanged_'. queueCount :: Queue sm qm so qo a -> Event Int queueCount q = Event $ \p -> readIORef (queueCountRef q) -- | Return the queue size statistics. queueCountStats :: Queue sm qm so qo a -> Event (TimingStats Int) queueCountStats q = Event $ \p -> readIORef (queueCountStatsRef q) -- | Signal when the 'queueCount' property value has changed. queueCountChanged :: Queue sm qm so qo a -> Signal Int queueCountChanged q = mapSignalM (const $ queueCount q) (queueCountChanged_ q) -- | Signal when the 'queueCount' property value has changed. queueCountChanged_ :: Queue sm qm so qo a -> Signal () queueCountChanged_ q = mapSignal (const ()) (enqueueStored q) <> mapSignal (const ()) (dequeueExtracted q) -- | Return the total number of input items that were stored. -- -- See also 'enqueueStoreCountChanged' and 'enqueueStoreCountChanged_'. enqueueStoreCount :: Queue sm qm so qo a -> Event Int enqueueStoreCount q = Event $ \p -> readIORef (enqueueStoreCountRef q) -- | Signal when the 'enqueueStoreCount' property value has changed. enqueueStoreCountChanged :: Queue sm qm so qo a -> Signal Int enqueueStoreCountChanged q = mapSignalM (const $ enqueueStoreCount q) (enqueueStoreCountChanged_ q) -- | Signal when the 'enqueueStoreCount' property value has changed. enqueueStoreCountChanged_ :: Queue sm qm so qo a -> Signal () enqueueStoreCountChanged_ q = mapSignal (const ()) (enqueueStored q) -- | Return the total number of requests for dequeueing the items, -- not taking into account the failed attempts to dequeue immediately -- without suspension. -- -- See also 'dequeueCountChanged' and 'dequeueCountChanged_'. dequeueCount :: Queue sm qm so qo a -> Event Int dequeueCount q = Event $ \p -> readIORef (dequeueCountRef q) -- | Signal when the 'dequeueCount' property value has changed. dequeueCountChanged :: Queue sm qm so qo a -> Signal Int dequeueCountChanged q = mapSignalM (const $ dequeueCount q) (dequeueCountChanged_ q) -- | Signal when the 'dequeueCount' property value has changed. dequeueCountChanged_ :: Queue sm qm so qo a -> Signal () dequeueCountChanged_ q = mapSignal (const ()) (dequeueRequested q) -- | Return the total number of output items that were actually dequeued. -- -- See also 'dequeueExtractCountChanged' and 'dequeueExtractCountChanged_'. dequeueExtractCount :: Queue sm qm so qo a -> Event Int dequeueExtractCount q = Event $ \p -> readIORef (dequeueExtractCountRef q) -- | Signal when the 'dequeueExtractCount' property value has changed. dequeueExtractCountChanged :: Queue sm qm so qo a -> Signal Int dequeueExtractCountChanged q = mapSignalM (const $ dequeueExtractCount q) (dequeueExtractCountChanged_ q) -- | Signal when the 'dequeueExtractCount' property value has changed. dequeueExtractCountChanged_ :: Queue sm qm so qo a -> Signal () dequeueExtractCountChanged_ q = mapSignal (const ()) (dequeueExtracted q) -- | Return the rate of the items that were stored: how many items -- per time. enqueueStoreRate :: Queue sm qm so qo a -> Event Double enqueueStoreRate q = Event $ \p -> do x <- readIORef (enqueueStoreCountRef q) let t0 = spcStartTime $ pointSpecs p t = pointTime p return (fromIntegral x / (t - t0)) -- | Return the rate of the requests for dequeueing the items: how many requests -- per time. It does not include the failed attempts to dequeue immediately -- without suspension. dequeueRate :: Queue sm qm so qo a -> Event Double dequeueRate q = Event $ \p -> do x <- readIORef (dequeueCountRef q) let t0 = spcStartTime $ pointSpecs p t = pointTime p return (fromIntegral x / (t - t0)) -- | Return the rate of the output items that were dequeued: how many items -- per time. dequeueExtractRate :: Queue sm qm so qo a -> Event Double dequeueExtractRate q = Event $ \p -> do x <- readIORef (dequeueExtractCountRef q) let t0 = spcStartTime $ pointSpecs p t = pointTime p return (fromIntegral x / (t - t0)) -- | Return the wait time from the time at which the item was stored in the queue to -- the time at which it was dequeued. -- -- See also 'queueWaitTimeChanged' and 'queueWaitTimeChanged_'. queueWaitTime :: Queue sm qm so qo a -> Event (SamplingStats Double) queueWaitTime q = Event $ \p -> readIORef (queueWaitTimeRef q) -- | Signal when the 'queueWaitTime' property value has changed. queueWaitTimeChanged :: Queue sm qm so qo a -> Signal (SamplingStats Double) queueWaitTimeChanged q = mapSignalM (const $ queueWaitTime q) (queueWaitTimeChanged_ q) -- | Signal when the 'queueWaitTime' property value has changed. queueWaitTimeChanged_ :: Queue sm qm so qo a -> Signal () queueWaitTimeChanged_ q = mapSignal (const ()) (dequeueExtracted q) -- | Return the dequeue wait time from the time at which the item was requested -- for dequeueing to the time at which it was actually dequeued. -- -- See also 'dequeueWaitTimeChanged' and 'dequeueWaitTimeChanged_'. dequeueWaitTime :: Queue sm qm so qo a -> Event (SamplingStats Double) dequeueWaitTime q = Event $ \p -> readIORef (dequeueWaitTimeRef q) -- | Signal when the 'dequeueWaitTime' property value has changed. dequeueWaitTimeChanged :: Queue sm qm so qo a -> Signal (SamplingStats Double) dequeueWaitTimeChanged q = mapSignalM (const $ dequeueWaitTime q) (dequeueWaitTimeChanged_ q) -- | Signal when the 'dequeueWaitTime' property value has changed. dequeueWaitTimeChanged_ :: Queue sm qm so qo a -> Signal () dequeueWaitTimeChanged_ q = mapSignal (const ()) (dequeueExtracted q) -- | Return a long-term average queue rate calculated as -- the average queue size divided by the average wait time. -- -- See also 'queueRateChanged' and 'queueRateChanged_'. queueRate :: Queue sm qm so qo a -> Event Double queueRate q = Event $ \p -> do x <- readIORef (queueCountStatsRef q) y <- readIORef (queueWaitTimeRef q) return (timingStatsMean x / samplingStatsMean y) -- | Signal when the 'queueRate' property value has changed. queueRateChanged :: Queue sm qm so qo a -> Signal Double queueRateChanged q = mapSignalM (const $ queueRate q) (queueRateChanged_ q) -- | Signal when the 'queueRate' property value has changed. queueRateChanged_ :: Queue sm qm so qo a -> Signal () queueRateChanged_ q = mapSignal (const ()) (enqueueStored q) <> mapSignal (const ()) (dequeueExtracted q) -- | Dequeue suspending the process if the queue is empty. dequeue :: (DequeueStrategy sm qm, EnqueueStrategy so qo) => Queue sm qm so qo a -- ^ the queue -> Process a -- ^ the dequeued value dequeue q = do t <- liftEvent $ dequeueRequest q requestResource (dequeueRes q) liftEvent $ dequeueExtract q t -- | Dequeue with the output priority suspending the process if the queue is empty. dequeueWithOutputPriority :: (DequeueStrategy sm qm, PriorityQueueStrategy so qo po) => Queue sm qm so qo a -- ^ the queue -> po -- ^ the priority for output -> Process a -- ^ the dequeued value dequeueWithOutputPriority q po = do t <- liftEvent $ dequeueRequest q requestResourceWithPriority (dequeueRes q) po liftEvent $ dequeueExtract q t -- | Try to dequeue immediately. tryDequeue :: DequeueStrategy sm qm => Queue sm qm so qo a -- ^ the queue -> Event (Maybe a) -- ^ the dequeued value of 'Nothing' tryDequeue q = do x <- tryRequestResourceWithinEvent (dequeueRes q) if x then do t <- dequeueRequest q fmap Just $ dequeueExtract q t else return Nothing -- | Enqueue the item. enqueue :: (EnqueueStrategy sm qm, DequeueStrategy so qo) => Queue sm qm so qo a -- ^ the queue -> a -- ^ the item to enqueue -> Event () enqueue = enqueueStore -- | Enqueue with the storing priority the item. enqueueWithStoringPriority :: (PriorityQueueStrategy sm qm pm, DequeueStrategy so qo) => Queue sm qm so qo a -- ^ the queue -> pm -- ^ the priority for storing -> a -- ^ the item to enqueue -> Event () enqueueWithStoringPriority = enqueueStoreWithPriority -- | Return a signal that notifies when the enqueued item -- is stored in the internal memory of the queue. enqueueStored :: Queue sm qm so qo a -> Signal a enqueueStored q = publishSignal (enqueueStoredSource q) -- | Return a signal that notifies when the dequeuing operation was requested. dequeueRequested :: Queue sm qm so qo a -> Signal () dequeueRequested q = publishSignal (dequeueRequestedSource q) -- | Return a signal that notifies when the item was extracted from the internal -- storage of the queue and prepared for immediate receiving by the dequeuing process. dequeueExtracted :: Queue sm qm so qo a -> Signal a dequeueExtracted q = publishSignal (dequeueExtractedSource q) -- | Store the item. enqueueStore :: (EnqueueStrategy sm qm, DequeueStrategy so qo) => Queue sm qm so qo a -- ^ the queue -> a -- ^ the item to be stored -> Event () enqueueStore q a = Event $ \p -> do let i = QueueItem { itemValue = a, itemStoringTime = pointTime p } invokeEvent p $ strategyEnqueue (enqueueStoringStrategy q) (queueStore q) i c <- readIORef (queueCountRef q) let c' = c + 1 t = pointTime p c' `seq` writeIORef (queueCountRef q) c' modifyIORef' (queueCountStatsRef q) (addTimingStats t c') modifyIORef' (enqueueStoreCountRef q) (+ 1) invokeEvent p $ releaseResourceWithinEvent (dequeueRes q) invokeEvent p $ triggerSignal (enqueueStoredSource q) (itemValue i) -- | Store with the priority the item. enqueueStoreWithPriority :: (PriorityQueueStrategy sm qm pm, DequeueStrategy so qo) => Queue sm qm so qo a -- ^ the queue -> pm -- ^ the priority for storing -> a -- ^ the item to be enqueued -> Event () enqueueStoreWithPriority q pm a = Event $ \p -> do let i = QueueItem { itemValue = a, itemStoringTime = pointTime p } invokeEvent p $ strategyEnqueueWithPriority (enqueueStoringStrategy q) (queueStore q) pm i c <- readIORef (queueCountRef q) let c' = c + 1 t = pointTime p c' `seq` writeIORef (queueCountRef q) c' modifyIORef' (queueCountStatsRef q) (addTimingStats t c') modifyIORef' (enqueueStoreCountRef q) (+ 1) invokeEvent p $ releaseResourceWithinEvent (dequeueRes q) invokeEvent p $ triggerSignal (enqueueStoredSource q) (itemValue i) -- | Accept the dequeuing request and return the current simulation time. dequeueRequest :: Queue sm qm so qo a -- ^ the queue -> Event Double -- ^ the current time dequeueRequest q = Event $ \p -> do modifyIORef' (dequeueCountRef q) (+ 1) invokeEvent p $ triggerSignal (dequeueRequestedSource q) () return $ pointTime p -- | Extract an item for the dequeuing request. dequeueExtract :: DequeueStrategy sm qm => Queue sm qm so qo a -- ^ the queue -> Double -- ^ the time of the dequeuing request -> Event a -- ^ the dequeued value dequeueExtract q t' = Event $ \p -> do i <- invokeEvent p $ strategyDequeue (enqueueStoringStrategy q) (queueStore q) c <- readIORef (queueCountRef q) let c' = c - 1 t = pointTime p c' `seq` writeIORef (queueCountRef q) c' modifyIORef' (queueCountStatsRef q) (addTimingStats t c') modifyIORef' (dequeueExtractCountRef q) (+ 1) invokeEvent p $ dequeueStat q t' i invokeEvent p $ triggerSignal (dequeueExtractedSource q) (itemValue i) return $ itemValue i -- | Update the statistics for the output wait time of the dequeuing operation -- and the wait time of storing in the queue. dequeueStat :: Queue sm qm so qo a -- ^ the queue -> Double -- ^ the time of the dequeuing request -> QueueItem a -- ^ the item and its input time -> Event () -- ^ the action of updating the statistics dequeueStat q t' i = Event $ \p -> do let t1 = itemStoringTime i t = pointTime p modifyIORef' (dequeueWaitTimeRef q) $ addSamplingStats (t - t') modifyIORef' (queueWaitTimeRef q) $ addSamplingStats (t - t1) -- | Signal whenever any property of the queue changes. -- -- The property must have the corresponded signal. There are also characteristics -- similar to the properties but that have no signals. As a rule, such characteristics -- already depend on the simulation time and therefore they may change at any -- time point. queueChanged_ :: Queue sm qm so qo a -> Signal () queueChanged_ q = mapSignal (const ()) (enqueueStored q) <> dequeueRequested q <> mapSignal (const ()) (dequeueExtracted q) -- | Return the summary for the queue with desciption of its -- properties and activities using the specified indent. queueSummary :: (Show sm, Show so) => Queue sm qm so qo a -> Int -> Event ShowS queueSummary q indent = do let sm = enqueueStoringStrategy q so = dequeueStrategy q null <- queueNull q count <- queueCount q countStats <- queueCountStats q enqueueStoreCount <- enqueueStoreCount q dequeueCount <- dequeueCount q dequeueExtractCount <- dequeueExtractCount q enqueueStoreRate <- enqueueStoreRate q dequeueRate <- dequeueRate q dequeueExtractRate <- dequeueExtractRate q waitTime <- queueWaitTime q dequeueWaitTime <- dequeueWaitTime q let tab = replicate indent ' ' return $ showString tab . showString "the storing (memory) strategy = " . shows sm . showString "\n" . showString tab . showString "the dequeueing (output) strategy = " . shows so . showString "\n" . showString tab . showString "empty? = " . shows null . showString "\n" . showString tab . showString "the current size = " . shows count . showString "\n" . showString tab . showString "the size statistics = \n\n" . timingStatsSummary countStats (2 + indent) . showString "\n\n" . showString tab . showString "the enqueue store count (number of the input items that were stored) = " . shows enqueueStoreCount . showString "\n" . showString tab . showString "the dequeue count (number of requests for dequeueing an item) = " . shows dequeueCount . showString "\n" . showString tab . showString "the dequeue extract count (number of the output items that were dequeued) = " . shows dequeueExtractCount . showString "\n" . showString tab . showString "the enqueue store rate (how many input items were stored per time) = " . shows enqueueStoreRate . showString "\n" . showString tab . showString "the dequeue rate (how many requests for dequeueing per time) = " . shows dequeueRate . showString "\n" . showString tab . showString "the dequeue extract rate (how many output items were dequeued per time) = " . shows dequeueExtractRate . showString "\n" . showString tab . showString "the wait time (when was stored -> when was dequeued) = \n\n" . samplingStatsSummary waitTime (2 + indent) . showString "\n\n" . showString tab . showString "the dequeue wait time (when was requested for dequeueing -> when was dequeued) = \n\n" . samplingStatsSummary dequeueWaitTime (2 + indent)