org.mmtk.plan.refcount

Class RCBaseCollector

java.lang.Object

org.mmtk.plan.CollectorContext

org.mmtk.plan.ParallelCollector

org.mmtk.plan.SimpleCollector

org.mmtk.plan.StopTheWorldCollector

org.mmtk.plan.refcount.RCBaseCollector

Direct Known Subclasses:

GenRCCollector, RCCollector

public abstract class RCBaseCollector
extends StopTheWorldCollector

This class implements the collector context for a reference counting collector. See Shahriyar et al for details of and rationale for the optimizations used here (http://dx.doi.org/10.1145/2258996.2259008). See Chapter 4 of Daniel Frampton's PhD thesis for details of and rationale for the cycle collection strategy used by this collector.

Field Summary

Fields

Modifier and Type	Field and Description
private BTTraceLocal	backupTrace
private RCDecBuffer	decBuffer
private ObjectReferenceDeque	modBuffer
protected ObjectReferenceDeque	newRootBuffer
private ObjectReferenceDeque	oldRootBuffer
private RCZero	zero

Fields inherited from class org.mmtk.plan.SimpleCollector

sanityLocal

Fields inherited from class org.mmtk.plan.ParallelCollector

group

Fields inherited from class org.mmtk.plan.CollectorContext

log

Constructor Summary

Constructors

Constructor and Description
RCBaseCollector() Constructor.

Method Summary

Modifier and Type	Method and Description
void	collect() Perform garbage collection
void	collectionPhase(short phaseId, boolean primary) Perform a (local, i.e.per-collector) collection phase.
TraceLocal	getCurrentTrace()
ObjectReferenceDeque	getModBuffer()
protected abstract TransitiveClosure	getModifiedProcessor()
protected abstract TraceLocal	getRootTrace()
protected static RCBase	global()

Methods inherited from class org.mmtk.plan.StopTheWorldCollector

concurrentCollect, concurrentCollectionPhase

Methods inherited from class org.mmtk.plan.ParallelCollector

parallelWorkerCount, parallelWorkerOrdinal, park, rendezvous, run

Methods inherited from class org.mmtk.plan.CollectorContext

allocCopy, copyCheckAllocator, getId, getLog, initCollector, postCopy

Methods inherited from class java.lang.Object

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

Field Detail

newRootBuffer

protected final ObjectReferenceDeque newRootBuffer

backupTrace

private final BTTraceLocal backupTrace

modBuffer

private final ObjectReferenceDeque modBuffer

oldRootBuffer

private final ObjectReferenceDeque oldRootBuffer

decBuffer

private final RCDecBuffer decBuffer

zero

private final RCZero zero

Constructor Detail

RCBaseCollector

public RCBaseCollector()

Constructor.

Method Detail

getModifiedProcessor

protected abstract TransitiveClosure getModifiedProcessor()

Returns:

the modified processor to use.

getRootTrace

protected abstract TraceLocal getRootTrace()

Returns:

the root trace to use.

collect

public void collect()

Perform garbage collection

Overrides:

collect in class StopTheWorldCollector

collectionPhase

public void collectionPhase(short phaseId,
                            boolean primary)

Description copied from class: SimpleCollector

Perform a (local, i.e.per-collector) collection phase.

Overrides:

collectionPhase in class SimpleCollector

Parameters:

phaseId - The unique phase identifier

primary - Should this thread be used to execute any single-threaded local operations?

global

protected static RCBase global()

Returns:

The active global plan as an RC instance.

getCurrentTrace

public final TraceLocal getCurrentTrace()

Overrides:

getCurrentTrace in class ParallelCollector

Returns:

The current trace instance.

getModBuffer

public final ObjectReferenceDeque getModBuffer()

Returns:

The current modBuffer instance.