VMemory subclass: #Clock
	instanceVariableNames: 'hand'
	classVariableNames: ''
	poolDictionaries: ''
	category: nil !

Clock comment: 'I am a Clock memory manager' !

!Clock methodsFor: 'instance initialization'!

init
	hand := 1.
	^super init.
! !

!Clock methodsFor: 'memory access'!

removePid: aPid
	super removePid: aPid.
	(hand > pages size) ifTrue: [ hand := 1 ].
!

insert: page
	pages add: page.
!

replace: page
	[ dirty includes: (pages at: hand)] whileTrue: [ dirty remove: (pages at: hand). hand := hand + 1. (hand > pages size) ifTrue: [ hand := 1 ] ].
	pages removeAtIndex: hand.
	self insert: page
! !