Package org.opendaylight.controller.cluster.raft.spi

Class EnabledRaftStorage

java.lang.Object

org.opendaylight.controller.cluster.raft.spi.RaftStorage

org.opendaylight.controller.cluster.raft.spi.EnabledRaftStorage

All Implemented Interfaces:

EntryStore, SnapshotStore

public final class EnabledRaftStorage
extends RaftStorage

A RaftStorage backing persistent mode of RaftActor operation.

Nested Class Summary

Nested classes/interfaces inherited from class org.opendaylight.controller.cluster.raft.spi.RaftStorage

RaftStorage.CancellableTask<T>

Field Summary

Fields inherited from class org.opendaylight.controller.cluster.raft.spi.RaftStorage

completer, compression, directory

Constructor Summary

Constructors

Constructor	Description
EnabledRaftStorage(RaftStorageCompleter completer, Path directory, CompressionType compression, FileBackedOutputStream.Configuration streamConfig, boolean mapped)

Method Summary

Modifier and Type	Method	Description
void	checkpointLastApplied(long commitJournalIndex)	Record a known value of lastApplied as a recovery optimization.
void	discardHead(long firstRetainedIndex)	Deletes journal entries up to, but not including, the given journalIndex.
void	discardTail(long firstRemovedIndex)	Delete entries starting from, and including, specified index.
EntryJournal	journal()	Returns the underlying EntryJournal.
protected void	postStart()
protected void	preStop()
void	startPersistEntry(ReplicatedLogEntry entry, RaftCallback<Long> callback)	Persists an entry to the applicable journal asynchronously.

Methods inherited from class org.opendaylight.controller.cluster.raft.spi.RaftStorage

addToStringAtrributes, completer, lastSnapshot, memberId, saveSnapshot, saveSnapshot, start, stop, streamToInstall, submitTask, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.opendaylight.controller.cluster.raft.spi.EntryStore

persistEntry

Constructor Details

EnabledRaftStorage

@NonNullByDefault
public EnabledRaftStorage(RaftStorageCompleter completer,
 Path directory,
 CompressionType compression,
 FileBackedOutputStream.Configuration streamConfig,
 boolean mapped)

Method Details

journal

@NonNullByDefault
public EntryJournal journal()

Returns the underlying EntryJournal.

Returns:

the underlying EntryJournal

startPersistEntry

@NonNullByDefault
public void startPersistEntry(ReplicatedLogEntry entry,
 RaftCallback<Long> callback)

Description copied from interface: EntryStore

Persists an entry to the applicable journal asynchronously.

Parameters:

entry - the journal entry to persist

callback - the callback when persistence is complete

discardHead

public void discardHead(long firstRetainedIndex)

Description copied from interface: EntryStore

Deletes journal entries up to, but not including, the given journalIndex.

Parameters:

firstRetainedIndex - the journalIndex of the first retained entry

discardTail

public void discardTail(long firstRemovedIndex)

Description copied from interface: EntryStore

Delete entries starting from, and including, specified index. The contract is that the callback will be invoked before RaftActor sees any other message.

Parameters:

firstRemovedIndex - the journalIndex of first entry to delete

checkpointLastApplied

public void checkpointLastApplied(long commitJournalIndex)

Description copied from interface: EntryStore

Record a known value of lastApplied as a recovery optimization. If we can recover this information, recovery can re-apply these entries before we attempt to talk to other members. It is okay to lose this marker, as in that case we will just apply those entries as part of being a follower or becoming a leader.

This amounts to persisting a lower bound on commitIndex, which is explicitly volatile state. We could remember that instead (or perhaps as well) -- but now we just derive it.

If we later discover that this index lies beyond current leader's commitIndex, we will ask for a complete snapshot -- which is not particularly nice, but should happen seldom enough for it not to matter much.

Parameters:

commitJournalIndex - the journalIndex of the entry which is covered by commitIndex and has been observed as lastApplied.

postStart

protected void postStart()
                  throws IOException

Specified by:

postStart in class RaftStorage

Throws:

IOException

preStop

protected void preStop()

Specified by:

preStop in class RaftStorage