Copyright	Copyright (c) 2009-2015, David Sorokin <david.sorokin@gmail.com>
License	BSD3
Maintainer	David Sorokin <david.sorokin@gmail.com>
Stability	experimental
Safe Haskell	None
Language	Haskell2010

Simulation.Aivika.Resource

Contents

Resource Types
Creating Resource
Resource Properties
Requesting for and Releasing Resource

Description

Tested with: GHC 7.8.3

This module defines the resource which can be acquired and then released by the discontinuous process Process. The resource can be either limited by the upper bound (run-time check), or it can have no upper bound. The latter is useful for modeling the infinite queue, for example.

Synopsis

Resource Types

type FCFSResource = Resource FCFS Source

The ordinary FCFS (First Come - First Serviced) resource.

type LCFSResource = Resource LCFS Source

The ordinary LCFS (Last Come - First Serviced) resource.

type SIROResource = Resource SIRO Source

The SIRO (Serviced in Random Order) resource.

type PriorityResource = Resource StaticPriorities Source

The resource with static priorities.

data Resource s Source

Represents the resource with strategy s applied for queuing the requests.

Instances

Eq (Resource s)

Creating Resource

newFCFSResource Source

Arguments

:: Int	the initial count (and maximal count too) of the resource
-> Simulation FCFSResource

Create a new FCFS resource with the specified initial count which value becomes the upper bound as well.

newFCFSResourceWithMaxCount Source

Arguments

:: Int	the initial count of the resource
-> Maybe Int	the maximum count of the resource, which can be indefinite
-> Simulation FCFSResource

Create a new FCFS resource with the specified initial and maximum counts, where Nothing means that the resource has no upper bound.

newLCFSResource Source

Arguments

:: Int	the initial count (and maximal count too) of the resource
-> Simulation LCFSResource

Create a new LCFS resource with the specified initial count which value becomes the upper bound as well.

newLCFSResourceWithMaxCount Source

Arguments

:: Int	the initial count of the resource
-> Maybe Int	the maximum count of the resource, which can be indefinite
-> Simulation LCFSResource

Create a new LCFS resource with the specified initial and maximum counts, where Nothing means that the resource has no upper bound.

newSIROResource Source

Arguments

:: Int	the initial count (and maximal count too) of the resource
-> Simulation SIROResource

Create a new SIRO resource with the specified initial count which value becomes the upper bound as well.

newSIROResourceWithMaxCount Source

Arguments

:: Int	the initial count of the resource
-> Maybe Int	the maximum count of the resource, which can be indefinite
-> Simulation SIROResource

Create a new SIRO resource with the specified initial and maximum counts, where Nothing means that the resource has no upper bound.

newPriorityResource Source

Arguments

:: Int	the initial count (and maximal count too) of the resource
-> Simulation PriorityResource

Create a new priority resource with the specified initial count which value becomes the upper bound as well.

newPriorityResourceWithMaxCount Source

Arguments

:: Int	the initial count of the resource
-> Maybe Int	the maximum count of the resource, which can be indefinite
-> Simulation PriorityResource

Create a new priority resource with the specified initial and maximum counts, where Nothing means that the resource has no upper bound.

newResource Source

Arguments

:: QueueStrategy s
=> s	the strategy for managing the queuing requests
-> Int	the initial count (and maximal count too) of the resource
-> Simulation (Resource s)

Create a new resource with the specified queue strategy and initial count. The last value becomes the upper bound as well.

newResourceWithMaxCount Source

Arguments

:: QueueStrategy s
=> s	the strategy for managing the queuing requests
-> Int	the initial count of the resource
-> Maybe Int	the maximum count of the resource, which can be indefinite
-> Simulation (Resource s)

Create a new resource with the specified queue strategy, initial and maximum counts, where Nothing means that the resource has no upper bound.

Resource Properties

resourceStrategy :: Resource s -> s Source

Return the strategy applied for queuing the requests.

resourceMaxCount :: Resource s -> Maybe Int Source

Return the maximum count of the resource, where Nothing means that the resource has no upper bound.

resourceCount :: Resource s -> Event Int Source

Return the current count of the resource.

Requesting for and Releasing Resource

requestResource Source

Arguments

:: EnqueueStrategy s
=> Resource s	the requested resource
-> Process ()

Request for the resource decreasing its count in case of success, otherwise suspending the discontinuous process until some other process releases the resource.

requestResourceWithPriority Source

Arguments

:: PriorityQueueStrategy s p
=> Resource s	the requested resource
-> p	the priority
-> Process ()

Request with the priority for the resource decreasing its count in case of success, otherwise suspending the discontinuous process until some other process releases the resource.

tryRequestResourceWithinEvent Source

Arguments

:: Resource s	the resource which we try to request for
-> Event Bool

Try to request for the resource decreasing its count in case of success and returning True in the Event monad; otherwise, returning False.

releaseResource Source

Arguments

:: DequeueStrategy s
=> Resource s	the resource to release
-> Process ()

Release the resource increasing its count and resuming one of the previously suspended processes as possible.

releaseResourceWithinEvent Source

Arguments

:: DequeueStrategy s
=> Resource s	the resource to release
-> Event ()

Release the resource increasing its count and resuming one of the previously suspended processes as possible.

usingResource Source

Arguments

:: EnqueueStrategy s
=> Resource s	the resource we are going to request for and then release in the end
-> Process a	the action we are going to apply having the resource
-> Process a	the result of the action

Acquire the resource, perform some action and safely release the resource in the end, even if the IOException was raised within the action.

usingResourceWithPriority Source

Arguments

:: PriorityQueueStrategy s p
=> Resource s	the resource we are going to request for and then release in the end
-> p	the priority
-> Process a	the action we are going to apply having the resource
-> Process a	the result of the action

Acquire the resource with the specified priority, perform some action and safely release the resource in the end, even if the IOException was raised within the action.