org.mmtk.plan.generational.copying

Class GenCopyCollector

java.lang.Object

org.mmtk.plan.CollectorContext

org.mmtk.plan.ParallelCollector

org.mmtk.plan.SimpleCollector

org.mmtk.plan.StopTheWorldCollector

org.mmtk.plan.generational.GenCollector

org.mmtk.plan.generational.copying.GenCopyCollector

public class GenCopyCollector
extends GenCollector

This class implements per-collector thread behavior and state for the GenCopy two-generational copying collector.

Specifically, this class defines semantics specific to the collection of the mature generation (GenCollector defines nursery semantics). In particular the mature space allocator is defined (for collection-time allocation into the mature space), and the mature space per-collector thread collection time semantics are defined.

See Also:

for a description of the GenCopy algorithm., GenCopy, GenCopyMutator, GenCollector, StopTheWorldCollector, CollectorContext

Field Summary

Fields

Modifier and Type	Field and Description
private CopyLocal	mature The allocator for the mature space
private GenCopyMatureTraceLocal	matureTrace The trace object for full-heap collections

Fields inherited from class org.mmtk.plan.generational.GenCollector

arrayRemset, los, modbuf, nurseryTrace, remset

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
GenCopyCollector() Constructor

Method Summary

Modifier and Type	Method and Description
Address	allocCopy(ObjectReference original, int bytes, int align, int offset, int allocator) Allocate space for copying an object (this method does not copy the object, it only allocates space)
void	collectionPhase(short phaseId, boolean primary) Perform a (local, i.e.per-collector) collection phase.
TraceLocal	getFullHeapTrace()
private static GenCopy	global()
void	postCopy(ObjectReference object, ObjectReference typeRef, int bytes, int allocator) Perform any post-copy actions.
protected void	showMature() Show the status of the mature allocator.

Methods inherited from class org.mmtk.plan.generational.GenCollector

getCurrentTrace

Methods inherited from class org.mmtk.plan.StopTheWorldCollector

collect, concurrentCollect, concurrentCollectionPhase

Methods inherited from class org.mmtk.plan.ParallelCollector

parallelWorkerCount, parallelWorkerOrdinal, park, rendezvous, run

Methods inherited from class org.mmtk.plan.CollectorContext

copyCheckAllocator, getId, getLog, initCollector

Methods inherited from class java.lang.Object

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

Field Detail

mature

private final CopyLocal mature

The allocator for the mature space

matureTrace

private final GenCopyMatureTraceLocal matureTrace

The trace object for full-heap collections

Constructor Detail

GenCopyCollector

public GenCopyCollector()

Constructor

Method Detail

allocCopy

public Address allocCopy(ObjectReference original,
                         int bytes,
                         int align,
                         int offset,
                         int allocator)

Allocate space for copying an object (this method does not copy the object, it only allocates space)

Overrides:

allocCopy in class CollectorContext

Parameters:

original - The object that is being copied.

bytes - The size of the space to be allocated (in bytes)

align - Required alignment for the copy

offset - Offset associated with the alignment.

allocator - The allocator associated with this request

Returns:

The address of the first byte of the allocated region

postCopy

public final void postCopy(ObjectReference object,
                           ObjectReference typeRef,
                           int bytes,
                           int allocator)

Perform any post-copy actions.

In this case we clear any bits used for this object's GC metadata.

Overrides:

postCopy in class CollectorContext

Parameters:

object - The newly allocated object.

typeRef - the type reference for the instance being created.

bytes - The size of the space to be allocated (in bytes).

allocator - The allocator statically assigned to this allocation.

collectionPhase

public void collectionPhase(short phaseId,
                            boolean primary)

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

Overrides:

collectionPhase in class GenCollector

Parameters:

phaseId - The unique phase identifier

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

global

private static GenCopy global()

Returns:

The active global plan as a GenCopy instance.

showMature

protected final void showMature()

Show the status of the mature allocator.

getFullHeapTrace

public final TraceLocal getFullHeapTrace()

Specified by:

getFullHeapTrace in class GenCollector

Returns:

The trace to use when collecting the mature space