Package org.apache.bookkeeper.bookie

Class EntryMemTable

java.lang.Object

org.apache.bookkeeper.bookie.EntryMemTable

All Implemented Interfaces:

AutoCloseable

Direct Known Subclasses:

EntryMemTableWithParallelFlusher

public class EntryMemTable
extends Object
implements AutoCloseable

The EntryMemTable holds in-memory representation to the entries not-yet flushed. When asked to flush, current EntrySkipList is moved to snapshot and is cleared. We continue to serve edits out of new EntrySkipList and backing snapshot until flusher reports in that the flush succeeded. At that point we let the snapshot go.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
(package private) static class	EntryMemTable.EntrySkipList	Entry skip list.

Field Summary

Fields

Modifier and Type	Field	Description
(package private) SkipListArena	allocator
(package private) final CheckpointSource	checkpointSource
(package private) final ServerConfiguration	conf
(package private) EntryMemTable.EntrySkipList	kvmap
(package private) final ReentrantReadWriteLock	lock
protected final EntryMemTableStats	memTableStats
(package private) final AtomicLong	size
(package private) final Semaphore	skipListSemaphore
(package private) final long	skipListSizeLimit
(package private) EntryMemTable.EntrySkipList	snapshot

Constructor Summary

Constructors

Constructor	Description
EntryMemTable(ServerConfiguration conf, CheckpointSource source, StatsLogger statsLogger)	Constructor.

Method Summary

Modifier and Type	Method	Description
long	addEntry(long ledgerId, long entryId, ByteBuffer entry, CacheCallback cb)	Write an update.
(package private) void	clearSnapshot(EntryMemTable.EntrySkipList keyValues)	The passed snapshot was successfully persisted; it can be let go.
void	close()
(package private) void	dump()
(package private) long	flush(SkipListFlusher flusher)	Flush snapshot and clear it.
long	flush(SkipListFlusher flusher, CheckpointSource.Checkpoint checkpoint)	Flush memtable until checkpoint.
(package private) long	flushSnapshot(SkipListFlusher flusher, CheckpointSource.Checkpoint checkpoint)	Flush snapshot and clear it iff its data is before checkpoint.
EntryKeyValue	getEntry(long ledgerId, long entryId)	Find the entry with given key.
EntryKeyValue	getLastEntry(long ledgerId)	Find the last entry with the given ledger key.
(package private) PrimitiveIterator.OfLong	getListOfEntriesOfLedger(long ledgerId)
(package private) boolean	isEmpty()	Check if there is data in the mem-table.
(package private) boolean	isSizeLimitReached()	Check if the entire heap usage for this EntryMemTable exceeds limit.
(package private) CheckpointSource.Checkpoint	snapshot()
(package private) CheckpointSource.Checkpoint	snapshot(CheckpointSource.Checkpoint oldCp)	Snapshot current EntryMemTable.

Methods inherited from class java.lang.Object

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

Field Details

kvmap

volatile EntryMemTable.EntrySkipList kvmap

snapshot

volatile EntryMemTable.EntrySkipList snapshot

conf

final ServerConfiguration conf

checkpointSource

final CheckpointSource checkpointSource

lock

final ReentrantReadWriteLock lock

size

final AtomicLong size

skipListSizeLimit

final long skipListSizeLimit

skipListSemaphore

final Semaphore skipListSemaphore

allocator

SkipListArena allocator

memTableStats

protected final EntryMemTableStats memTableStats

Constructor Details

EntryMemTable

public EntryMemTable(ServerConfiguration conf,
 CheckpointSource source,
 StatsLogger statsLogger)

Constructor.

Parameters:

conf - Server configuration

Method Details

dump

void dump()

snapshot

CheckpointSource.Checkpoint snapshot()
                              throws IOException

Throws:

IOException

snapshot

CheckpointSource.Checkpoint snapshot(CheckpointSource.Checkpoint oldCp)
                              throws IOException

Snapshot current EntryMemTable. if given oldCp is older than current checkpoint, we don't do any snapshot. If snapshot happened, we return the checkpoint of the snapshot.

Parameters:

oldCp - checkpoint

Returns:

checkpoint of the snapshot, null means no snapshot

Throws:

IOException

flush

long flush(SkipListFlusher flusher)
    throws IOException

Flush snapshot and clear it.

Throws:

IOException

flush

public long flush(SkipListFlusher flusher,
 CheckpointSource.Checkpoint checkpoint)
           throws IOException

Flush memtable until checkpoint.

Parameters:

checkpoint - all data before this checkpoint need to be flushed.

Throws:

IOException

flushSnapshot

long flushSnapshot(SkipListFlusher flusher,
 CheckpointSource.Checkpoint checkpoint)
            throws IOException

Flush snapshot and clear it iff its data is before checkpoint. Only this function change non-empty this.snapshot.

EntryMemTableWithParallelFlusher overrides this flushSnapshot method. So any change in functionality/behavior/characteristic of this method should also reflect in EntryMemTableWithParallelFlusher's flushSnapshot method.

Throws:

IOException

clearSnapshot

void clearSnapshot(EntryMemTable.EntrySkipList keyValues)

The passed snapshot was successfully persisted; it can be let go.

Parameters:

keyValues - The snapshot to clean out.

addEntry

public long addEntry(long ledgerId,
 long entryId,
 ByteBuffer entry,
 CacheCallback cb)
              throws IOException

Write an update.

Parameters:

entry -

Returns:

approximate size of the passed key and value.

Throws:

IOException

getEntry

public EntryKeyValue getEntry(long ledgerId,
 long entryId)
                       throws IOException

Find the entry with given key.

Parameters:

ledgerId -

entryId -

Returns:

the entry kv or null if none found.

Throws:

IOException

getLastEntry

public EntryKeyValue getLastEntry(long ledgerId)
                           throws IOException

Find the last entry with the given ledger key.

Parameters:

ledgerId -

Returns:

the entry kv or null if none found.

Throws:

IOException

isSizeLimitReached

boolean isSizeLimitReached()

Check if the entire heap usage for this EntryMemTable exceeds limit.

isEmpty

boolean isEmpty()

Check if there is data in the mem-table.

Returns:

close

public void close()
           throws Exception

Specified by:

close in interface AutoCloseable

Throws:

Exception

getListOfEntriesOfLedger

PrimitiveIterator.OfLong getListOfEntriesOfLedger(long ledgerId)