io.atomix.copycat.server.storage.compaction

Class Compactor

java.lang.Object

io.atomix.copycat.server.storage.compaction.Compactor

All Implemented Interfaces:

AutoCloseable

public class Compactor
extends Object
implements AutoCloseable

Manages compaction of log Segments in a pool of background threads.

The compactor is responsible for managing log compaction processes. Log Compaction processes are run in a pool of background threads of the configured number of Storage.compactionThreads(). Compaction.MINOR and Compaction.MAJOR executions are scheduled according to the configured Storage.minorCompactionInterval() and Storage.majorCompactionInterval() respectively. Compaction can also be run synchronously via compact() or compact(Compaction).

When a Compaction is executed either synchronously or asynchronously, the compaction's associated CompactionManager is called to build a list of CompactionTasks to run. Compaction tasks are run in parallel in the compaction thread pool. However, the compactor will not allow multiple compaction executions to run in parallel. If a compaction is attempted while another compaction is already running, it will be ignored.

Author:

Constructor Summary

Constructors

Constructor and Description
Compactor(Storage storage, SegmentManager segments, ScheduledExecutorService executor)

Method Summary

Modifier and Type	Method and Description
void	close() Closes the log compactor.
CompletableFuture<Void>	compact() Compacts the log using the default Compaction.MINOR compaction strategy.
CompletableFuture<Void>	compact(Compaction compaction) Compacts the log using the given Compaction.
long	compactIndex() Returns a the index up to which the log can be compacted.
Compaction.Mode	getDefaultCompactionMode() Returns the default compaction mode.
long	majorIndex() Returns the maximum compaction index for major compaction.
Compactor	majorIndex(long index) Sets the maximum compaction index for major compaction.
long	minorIndex() Returns the maximum compaction index for minor compaction.
Compactor	minorIndex(long index) Sets the maximum compaction index for minor compaction.
long	snapshotIndex() Returns the maximum index up to which snapshotted commands can be removed during compaction.
Compactor	snapshotIndex(long index) Sets the snapshot index to indicate commands entries that can be removed during compaction.
Compactor	withDefaultCompactionMode(Compaction.Mode mode) Sets the default compaction mode.

Methods inherited from class java.lang.Object

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

Constructor Detail

Compactor

public Compactor(Storage storage,
                 SegmentManager segments,
                 ScheduledExecutorService executor)

Method Detail

withDefaultCompactionMode

public Compactor withDefaultCompactionMode(Compaction.Mode mode)

Sets the default compaction mode.

Parameters:

mode - The default compaction mode.

Returns:

The compactor.

Throws:

NullPointerException - if the compaction mode is null

IllegalArgumentException - if the compaction mode is Compaction.Mode.DEFAULT

getDefaultCompactionMode

public Compaction.Mode getDefaultCompactionMode()

Returns the default compaction mode.

Returns:

The default compaction mode.

minorIndex

public Compactor minorIndex(long index)

Sets the maximum compaction index for minor compaction.

Parameters:

index - The maximum compaction index for minor compaction.

Returns:

The log compactor.

minorIndex

public long minorIndex()

Returns the maximum compaction index for minor compaction.

Returns:

The maximum compaction index for minor compaction.

majorIndex

public Compactor majorIndex(long index)

Sets the maximum compaction index for major compaction.

Parameters:

index - The maximum compaction index for major compaction.

Returns:

The log compactor.

majorIndex

public long majorIndex()

Returns the maximum compaction index for major compaction.

Returns:

The maximum compaction index for major compaction.

snapshotIndex

public Compactor snapshotIndex(long index)

Sets the snapshot index to indicate commands entries that can be removed during compaction.

Parameters:

index - The maximum index up to which snapshotted commands can be removed.

Returns:

The log compactor.

snapshotIndex

public long snapshotIndex()

Returns the maximum index up to which snapshotted commands can be removed during compaction.

Returns:

The maximum index up to which snapshotted commands can be removed during compaction.

compactIndex

public long compactIndex()

Returns a the index up to which the log can be compacted.

Returns:

The index up to which the log can be compacted.

compact

public CompletableFuture<Void> compact()

Compacts the log using the default Compaction.MINOR compaction strategy.

Returns:

A completable future to be completed once the log has been compacted.

compact

public CompletableFuture<Void> compact(Compaction compaction)

Compacts the log using the given Compaction.

The provided CompactionManager will be queried for a list of CompactionTasks to run. Tasks will be run in parallel in a pool of background threads, and the returned CompletableFuture will be completed once those tasks have completed.

Parameters:

compaction - The compaction strategy.

Returns:

A completable future to be completed once the log has been compacted.

close

public void close()

Closes the log compactor.

When the compactor is closed, existing compaction tasks will be allowed to complete, future scheduled compactions will be cancelled, and the underlying ScheduledExecutorService will be shut down.

Specified by:

close in interface AutoCloseable