Package org.apache.jackrabbit.oak.segment

Class ParallelCompactor

java.lang.Object

org.apache.jackrabbit.oak.segment.Compactor

org.apache.jackrabbit.oak.segment.CheckpointCompactor

org.apache.jackrabbit.oak.segment.ParallelCompactor

public class ParallelCompactor
extends CheckpointCompactor

This compactor implementation leverages the tree structure of the repository for concurrent compaction. It explores the tree breadth-first until the target node count (10000) is reached. Every node at this depth will be an entry point for asynchronous compaction. After the exploration phase, the main thread will collect these compaction results and write their parents' node state to disk.

Field Summary

Fields inherited from class org.apache.jackrabbit.oak.segment.CheckpointCompactor

compactor, gcListener

Constructor Summary

Constructors

Constructor	Description
ParallelCompactor(@NotNull GCMonitor gcListener, @NotNull CompactionWriter writer, @NotNull GCNodeWriteMonitor compactionMonitor, int nThreads)	Create a new instance based on the passed arguments.

Method Summary

Modifier and Type	Method	Description
protected @Nullable CompactedNodeState	compactDownWithDelegate(@NotNull NodeState before, @NotNull NodeState after, @NotNull Canceller hardCanceller, @NotNull Canceller softCanceller)	Delegate compaction to another, usually simpler, implementation.
protected @Nullable CompactedNodeState	compactWithDelegate(@NotNull NodeState before, @NotNull NodeState after, @NotNull NodeState onto, @NotNull Canceller canceller)

Methods inherited from class org.apache.jackrabbit.oak.segment.CheckpointCompactor

compact, compactDown

Methods inherited from class org.apache.jackrabbit.oak.segment.Compactor

compactDown, compactUp, compactUp

Methods inherited from class java.lang.Object

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

Constructor Detail

ParallelCompactor

public ParallelCompactor(@NotNull
                         @NotNull GCMonitor gcListener,
                         @NotNull
                         @NotNull CompactionWriter writer,
                         @NotNull
                         @NotNull GCNodeWriteMonitor compactionMonitor,
                         int nThreads)

Create a new instance based on the passed arguments.

Parameters:

gcListener - listener receiving notifications about the garbage collection process

writer - segment writer used to serialise to segments

compactionMonitor - notification call back for each compacted nodes, properties, and binaries

nThreads - number of threads to use for parallel compaction, negative numbers are interpreted relative to the number of available processors

Method Detail

compactDownWithDelegate

@Nullable
protected @Nullable CompactedNodeState compactDownWithDelegate(@NotNull
                                                               @NotNull NodeState before,
                                                               @NotNull
                                                               @NotNull NodeState after,
                                                               @NotNull
                                                               @NotNull Canceller hardCanceller,
                                                               @NotNull
                                                               @NotNull Canceller softCanceller)
                                                        throws java.io.IOException

Description copied from class: CheckpointCompactor

Delegate compaction to another, usually simpler, implementation.

Overrides:

compactDownWithDelegate in class CheckpointCompactor

Throws:

java.io.IOException

compactWithDelegate

@Nullable
protected @Nullable CompactedNodeState compactWithDelegate(@NotNull
                                                           @NotNull NodeState before,
                                                           @NotNull
                                                           @NotNull NodeState after,
                                                           @NotNull
                                                           @NotNull NodeState onto,
                                                           @NotNull
                                                           @NotNull Canceller canceller)
                                                    throws java.io.IOException

Overrides:

compactWithDelegate in class CheckpointCompactor

Throws:

java.io.IOException