contur::OptimalReplacement Class Reference

Optimal page replacement (Belady's algorithm). More...

#include <optimal_replacement.h>

Inheritance diagram for contur::OptimalReplacement:

Public Member Functions
	OptimalReplacement (std::vector< FrameId > futureAccesses)
	Constructs with a known future access sequence.
	~OptimalReplacement () override
	Destroys optimal replacement policy.
	OptimalReplacement (const OptimalReplacement &)=delete
	Copy construction is disabled.
OptimalReplacement &	operator= (const OptimalReplacement &)=delete
	Copy assignment is disabled.
	OptimalReplacement (OptimalReplacement &&) noexcept
	Move-constructs policy state.
OptimalReplacement &	operator= (OptimalReplacement &&) noexcept
	Move-assigns policy state.
std::string_view	name () const noexcept override
	Returns the name of the algorithm (e.g., "FIFO", "LRU").
FrameId	selectVictim (const PageTable &pageTable) override
	Selects a victim frame to evict.
void	onAccess (FrameId frame) override
	Notifies the policy that a frame was accessed (read or write).
void	onLoad (FrameId frame) override
	Notifies the policy that a new page was loaded into a frame.
void	reset () override
	Resets the policy's internal state.
Public Member Functions inherited from contur::IPageReplacementPolicy
virtual	~IPageReplacementPolicy ()=default

Private Attributes
std::unique_ptr< Impl >	impl_

Detailed Description

Optimal page replacement (Belady's algorithm).

Evicts the page that will not be used for the longest time in the future. Requires the complete future access sequence to be known in advance. This is impractical for real systems but serves as a theoretical baseline for comparing other algorithms' performance.

Definition at line 19 of file optimal_replacement.h.

Constructor & Destructor Documentation

OptimalReplacement() [1/3]

contur::OptimalReplacement::OptimalReplacement ( std::vector< FrameId > futureAccesses )

explicit

Constructs with a known future access sequence.

Parameters

futureAccesses

Ordered list of FrameIds that will be accessed.

Referenced by operator=(), operator=(), OptimalReplacement(), and OptimalReplacement().

~OptimalReplacement()

contur::OptimalReplacement::~OptimalReplacement ( )

override

Destroys optimal replacement policy.

OptimalReplacement() [2/3]

contur::OptimalReplacement::OptimalReplacement ( const OptimalReplacement & )

delete

Copy construction is disabled.

References OptimalReplacement().

OptimalReplacement() [3/3]

contur::OptimalReplacement::OptimalReplacement ( OptimalReplacement && )

noexcept

Move-constructs policy state.

References OptimalReplacement().

Member Function Documentation

name()

std::string_view contur::OptimalReplacement::name ( ) const

nodiscardoverridevirtualnoexcept

Returns the name of the algorithm (e.g., "FIFO", "LRU").

Implements contur::IPageReplacementPolicy.

References name().

Referenced by name().

onAccess()

void contur::OptimalReplacement::onAccess ( FrameId frame )

overridevirtual

Notifies the policy that a frame was accessed (read or write).

Implements contur::IPageReplacementPolicy.

References onAccess().

Referenced by onAccess().

onLoad()

void contur::OptimalReplacement::onLoad ( FrameId frame )

overridevirtual

Notifies the policy that a new page was loaded into a frame.

Implements contur::IPageReplacementPolicy.

References onLoad().

Referenced by onLoad().

operator=() [1/2]

OptimalReplacement & contur::OptimalReplacement::operator= ( const OptimalReplacement & )

delete

Copy assignment is disabled.

References OptimalReplacement().

operator=() [2/2]

OptimalReplacement & contur::OptimalReplacement::operator= ( OptimalReplacement && )

noexcept

Move-assigns policy state.

References OptimalReplacement().

reset()

void contur::OptimalReplacement::reset ( )

overridevirtual

Resets the policy's internal state.

Implements contur::IPageReplacementPolicy.

References reset().

Referenced by reset().

selectVictim()

FrameId contur::OptimalReplacement::selectVictim ( const PageTable & pageTable )

nodiscardoverridevirtual

Selects a victim frame to evict.

Parameters

pageTable

The current page table state.

Returns

The FrameId of the frame to evict.

Implements contur::IPageReplacementPolicy.

References selectVictim().

Referenced by selectVictim().

Member Data Documentation

impl_

std::unique_ptr<Impl> contur::OptimalReplacement::impl_

private

Definition at line 57 of file optimal_replacement.h.

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The documentation for this class was generated from the following file:

• include/contur/memory/optimal_replacement.h