org.apache.cassandra.db.commitlog

Class AbstractCommitLogSegmentManager

java.lang.Object

org.apache.cassandra.db.commitlog.AbstractCommitLogSegmentManager

Direct Known Subclasses:

CommitLogSegmentManagerCDC, CommitLogSegmentManagerStandard

public abstract class AbstractCommitLogSegmentManager
extends java.lang.Object

Performs eager-creation of commit log segments in a background thread. All the public methods are thread safe.

Field Summary

Fields

Modifier and Type	Field and Description
protected CommitLogSegment	allocatingFrom The segment we are currently allocating commit log records to
protected CommitLog	commitLog
protected boolean	run

Method Summary

Modifier and Type	Method and Description
protected void	advanceAllocatingFrom(CommitLogSegment old) Fetches a new segment from the queue, signaling the management thread to create a new one if necessary, and "activates" it.
abstract CommitLogSegment.Allocation	allocate(Mutation mutation, int size) Allocate a segment within this CLSM.
void	awaitTermination() Returns when the management thread terminates.
java.util.Collection<CommitLogSegment>	getActiveSegments()
boolean	manages(java.lang.String name)
long	onDiskSize()
abstract void	shutdown() Shut down the CLSM.
void	stopUnsafe(boolean deleteSegments) Stops CL, for testing purposes.
void	sync(boolean syncAllSegments) Forces a disk flush on the commit log files that need it.
protected void	wakeManager()

Methods inherited from class java.lang.Object

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

Field Detail

allocatingFrom

protected volatile CommitLogSegment allocatingFrom

The segment we are currently allocating commit log records to

run

protected volatile boolean run

commitLog

protected final CommitLog commitLog

Method Detail

shutdown

public abstract void shutdown()

Shut down the CLSM. Used both during testing and during regular shutdown, so needs to stop everything.

allocate

public abstract CommitLogSegment.Allocation allocate(Mutation mutation,
                                                     int size)

Allocate a segment within this CLSM. Should either succeed or throw.

advanceAllocatingFrom

protected void advanceAllocatingFrom(CommitLogSegment old)

Fetches a new segment from the queue, signaling the management thread to create a new one if necessary, and "activates" it. Blocks until a new segment is allocated and the thread requesting an advanceAllocatingFrom is signalled. WARNING: Assumes segment management thread always succeeds in allocating a new segment or kills the JVM.

wakeManager

protected void wakeManager()

onDiskSize

public long onDiskSize()

Returns:

the space (in bytes) used by all segment files.

manages

public boolean manages(java.lang.String name)

Parameters:

name - the filename to check

Returns:

true if file is managed by this manager.

stopUnsafe

public void stopUnsafe(boolean deleteSegments)

Stops CL, for testing purposes. DO NOT USE THIS OUTSIDE OF TESTS. Only call this after the AbstractCommitLogService is shut down.

awaitTermination

public void awaitTermination()
                      throws java.lang.InterruptedException

Returns when the management thread terminates.

Throws:

java.lang.InterruptedException

getActiveSegments

public java.util.Collection<CommitLogSegment> getActiveSegments()

Returns:

a read-only collection of the active commit log segments

sync

public void sync(boolean syncAllSegments)
          throws java.io.IOException

Forces a disk flush on the commit log files that need it. Blocking.

Throws:

java.io.IOException