1 / 20

Tray allocation for a sortation system Concurrent version Iteration II

Tray allocation for a sortation system Concurrent version Iteration II. TI-VDM2 Project by José Antonio Esparza and Kim Bjerge. Contents of presentation. Simulation scenario in time (ms) The concurrent version of the system (Class) Object diagram concurrent version (Object)

tim
Télécharger la présentation

Tray allocation for a sortation system Concurrent version Iteration II

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Tray allocation for a sortation systemConcurrent versionIteration II TI-VDM2 Project by José Antonio Esparza and Kim Bjerge Sortation System, TrayAllocation

  2. Contents of presentation • Simulation scenario in time (ms) • The concurrent version of the system (Class) • Object diagram concurrent version (Object) • Behavior of sequential model (Sequence) • Behavior of concurrent model (Sequence) • VDM - Concurrent model (Vs. sequential) • 10 slides • Introduction to RT model (Deployment) Sortation System, TrayAllocation

  3. Simulation in time (ms) instead of TraySteps Concurrent simulation scenario (time in ms) mk_(7200,[mk_(40,1,100), mk_(70,2,200), mk_(100,3,300), mk_(200,1,400), mk_(210,2,500), mk_(220,3,100) Sequential simulation scenario (TraySteps) mk_(21,[mk_(0,1,100), mk_(0,2,200), mk_(0,3,300), mk_(1,1,400), mk_(1,2,500), mk_(1,3,100), Sortation System, Tray Allocation

  4. 1.- The concurrent version of the system Sortation System, Tray Allocation

  5. 2.- Object diagram concurrent version Sortation System, Tray Allocation

  6. 4. Behavior of sequential model (Sequence) Sortation System, Tray Allocation

  7. 5.- Behavior of concurrent model (Sequence) Sortation System, Tray Allocation

  8. VDM - World -- Concurrent model public static timerRef : TimeStamp := new TimeStamp(); start(env); -- Start thread in enviroment -- Sequential model for all t in set {0,...,loader.GetNumTimeSteps()} do env.TimeStep(t); Sortation System, Tray Allocation

  9. VDM - SorterEnviromentstartingthreads busy : bool := true; public static trayStep : TrayStep := new TrayStep(Speed); ….. public isFinished : () ==> () isFinished() == skip; sync per isFinished => not busy; thread ( -- Start all threads in the system start (trayStep); start (sc.allocator); for all i in set {1,...,TrayAllocator`NumOfInductions} do start (inductionGroup(i)); Sortation System, TrayAllocation

  10. VDM - SorterEnviromentfeedinductions whilebusy do ( for all i in set {1,...,TrayAllocator`NumOfInductions} do ( let size = itemLoader.GetItemAtTimeStep(World`timerRef.GetTime(), i) in if(size > 0) then ( itemId:= itemId + 1; inductionGroup(i).FeedItem(new Item(size, itemId)); ); ); Sortation System, Tray Allocation

  11. VDM - SorterEnviromentadvance time World`timerRef.WaitRelative(0); World`timerRef.NotifyAndIncTime(); World`timerRef.Awake(); -- Check if simulation is finish if(World`timerRef.GetTime() >= itemLoader.GetNumTimeSteps()) then busy:= false; ); Sortation System, Tray Allocation

  12. VDM –TrayStepsync and thread public WaitSteps : nat ==> () WaitSteps(steps) == ( AddToMap(threadid, counts + steps); Wait(); ); Wait: () ==> () Wait() == skip; sync per Wait => threadid not in set domwaitTrayStepMap; thread whiletrue do ( IncCounts(); NotifyWatingThreads(); World`timerRef.WaitRelative(stepTime); World`timerRef.NotifyAll(); World`timerRef.Awake(); ) Sortation System, Tray Allocation

  13. VDM - InductionControllerthread and sync -- Enviroment and TrayAllocatorthreads mutex (FeedItem, InductFirstItem); -- TrayAllocator and InductionControllerthreads mutex (InductFirstItem); mutex (IncrementPriority); mutex (GetFirstItem, IncrementPriority, InductFirstItem); -- Block thread if no items to induct per InductNextItem => len items > 0; per ItemsToInduct => len items > 0; thread ( while (ItemsToInduct()) do ( allocator.RequestTray(threadid, selfIC, GetFirstItem()); allocator.Wait(); SorterEnviroment`trayStep.WaitSteps(InductionRate); -- World`timerRef.WaitRelative(InductionRateInMs); -- World`timerRef.Awake(); ); ); Sortation System, Tray Allocation

  14. VDM - InductionController new operations GetFirstItem: () ==> Item GetFirstItem() == returnhd items pre len items <> 0; public InductFirstItem: () ==> () InductFirstItem() == atomic -- Due to invariant ( items := tl items; priority := 0 ) prelen items <> 0; public IncrementPriority: () ==> () IncrementPriority() == priority := priority + 1; -- Increment priority wait counter ItemsToInduct: () ==> bool ItemsToInduct () == return len items <> 0; Sortation System, Tray Allocation

  15. TrayAllocatorthread and sync -- Map of waiting inductions with an item to be inducted itemsToInduct : map nat to (InductionController * Item) := {|->}; ….. mutex(RequestTray); -- Only allows one induction at a time to induct items -- Mutex to ensure syncronization between InductionController and TrayAllocator mutex(RequestTray, CheckItemsToInduct); -- Permission predicate on Wait operation per Wait => threadid not in set domitemsToInduct; thread while (true) do ( -- Wait time equal to one tray step SorterEnviroment`trayStep.WaitSteps(1); CardReader(TrayStep`GetCounts() mod TrayAllocator`NumOfTrays + 1, <Empty>); -- Induct items for all waiting inductions CheckItemsToInduct(); ); Sortation System, Tray Allocation

  16. VDM - TrayAllocatorCheckItemsToInduct CheckItemsToInduct: () ==> () CheckItemsToInduct () == ( -- Induct items for all waiting inductions for all t in set domitemsToInduct do let mk_(ic, item) = itemsToInduct(t) in ifInductItem(ic, item) then ( ic.InductFirstItem(); RemoveItem(t); ) else ic.IncrementPriority(); ); Sortation System, Tray Allocation

  17. VDM - TrayAllocator new operations -- Called by InductionController thread requesting to induct item public RequestTray: nat * InductionController * Item ==> () RequestTray (t, ic, item) == AddItem(t, ic, item) pre t not in set domitemsToInduct; -- Thread blocked until removed from Map itemsToInduct public Wait: () ==> () Wait() == skip; -- Add induction waiting with item to induct AddItem: nat * InductionController * Item ==> () AddItem (t, ic, item) == itemsToInduct := itemsToInductmunion {t |-> mk_(ic, item)} pre t not in set domitemsToInduct; -- Remove induction waiting with item to induct RemoveItem: nat ==> () RemoveItem (t) == itemsToInduct := {t} <-: itemsToInduct pre t in set domitemsToInduct; Sortation System, Tray Allocation

  18. VDM – SC prepared for RT model class SC instancevariables public static ic1 : InductionController := new InductionController(1); public static ic2 : InductionController := new InductionController(2); public static ic3 : InductionController := new InductionController(3); public static inductionGroup : seq of InductionController := [ic1, ic2, ic3]; public static allocator : TrayAllocator := new TrayAllocator(inductionGroup); operations public SC: () ==> SC SC() == ( ); -- Create assignments releations between objects public CreateAssignments: SorterEnviroment ==> () CreateAssignments (env) == ( ic1.AssignAllocator(allocator); ic2.AssignAllocator(allocator); ic3.AssignAllocator(allocator); env.AssignInductionGroup(inductionGroup); ); Sortation System, Tray Allocation

  19. Next step for RT model • Deploythreads to CPU’s • CPU for eachinduction • TrayAllocatoron a central CPU controller • Firstdeployed RT version ready Outstanding for RT model – nexttodo • RemoveTimeStamp and TrayStep • Makeperiodicthread for eg. TrayAllocator • Still need time somehow? • Look at how to useasyn operations? Sortation System, Tray Allocation

  20. First RT version made for SC – system instance variables cpuIC1 : CPU := new CPU (<FCFS>,1E6); cpuIC2 : CPU := new CPU (<FCFS>,1E6); cpuIC3 : CPU := new CPU (<FP>,1E9); cpuTA4 : CPU := new CPU (<FCFS>,1E6); bus1 : BUS := new BUS (<FCFS>,1E3,{cpuIC1,cpuTA4}); bus2 : BUS := new BUS (<FCFS>,1E3,{cpuIC2,cpuTA4}); bus3 : BUS := new BUS (<FCFS>,1E3,{cpuIC3,cpuTA4}); …. operations public SC: () ==> SC SC() == ( cpuIC1.deploy(ic1); cpuIC2.deploy(ic2); cpuIC3.deploy(ic3); cpuTA4.deploy(allocator); ); Sortation System, Tray Allocation

More Related