org.mmtk.plan

Class ParallelCollectorGroup

java.lang.Object

org.mmtk.plan.ParallelCollectorGroup

public class ParallelCollectorGroup
extends Object

This class represents a pool of collector contexts that can be triggered to perform collection activity.

Field Summary

Fields

Modifier and Type	Field and Description
private boolean	aborted Is there an abort request outstanding?
private ParallelCollector[]	contexts The collector context instances operating within this group
private int	contextsParked The number of threads that are currently parked
private int	currentRendezvousCounter Which rendezvous counter is currently in use
private Monitor	lock Lock used to manage group state.
private String	name The name of this collector context group.
private int[]	rendezvousCounter Used to count threads during calls to rendezvous()
private int	triggerCount The number of cycles triggered

Constructor Summary

Constructors

Constructor and Description
ParallelCollectorGroup(String name)

Method Summary

Modifier and Type	Method and Description
void	abortCycle() Signal that you would like the threads to park abruptly.
int	activeWorkerCount()
void	initGroup(int size, Class<? extends ParallelCollector> klass) Initialize the collector context group.
boolean	isAborted()
boolean	isMember(CollectorContext context) Is the given context and member of this group.
void	park(ParallelCollector context) Park the given collector in the group.
int	rendezvous() Rendezvous with other active threads in this group.
void	triggerCycle() Wake up the parked threads in this group.
void	waitForCycle() Wait until the group is idle.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

name

private final String name

The name of this collector context group.

contexts

private ParallelCollector[] contexts

The collector context instances operating within this group

lock

private Monitor lock

Lock used to manage group state.

triggerCount

private volatile int triggerCount

The number of cycles triggered

contextsParked

private volatile int contextsParked

The number of threads that are currently parked

aborted

private volatile boolean aborted

Is there an abort request outstanding?

rendezvousCounter

private final int[] rendezvousCounter

Used to count threads during calls to rendezvous()

currentRendezvousCounter

private volatile int currentRendezvousCounter

Which rendezvous counter is currently in use

Constructor Detail

ParallelCollectorGroup

public ParallelCollectorGroup(String name)

Parameters:

name - human-readable name of the collector group

Method Detail

activeWorkerCount

public int activeWorkerCount()

Returns:

The number of active collector contexts.

initGroup

public void initGroup(int size,
                      Class<? extends ParallelCollector> klass)

Initialize the collector context group.

Parameters:

size - The number of collector contexts within the group.

klass - The type of collector context to create.

triggerCycle

public void triggerCycle()

Wake up the parked threads in this group.

abortCycle

public void abortCycle()

Signal that you would like the threads to park abruptly. Has no effect if no cycle is active.

isAborted

public boolean isAborted()

Returns:

whether the cycle has been aborted

waitForCycle

public void waitForCycle()

Wait until the group is idle.

park

public void park(ParallelCollector context)

Park the given collector in the group. The given context must be a member of this group.

Parameters:

context - The context to park.

isMember

public boolean isMember(CollectorContext context)

Is the given context and member of this group.

Parameters:

context - The context to pass.

Returns:

true if the context is a member.

rendezvous

public int rendezvous()

Rendezvous with other active threads in this group.

Returns:

The order in which you entered the rendezvous.