org.apache.hadoop.hbase.io.hfile.bucket

Class BucketCache.BucketEntry

java.lang.Object

org.apache.hadoop.hbase.io.hfile.bucket.BucketCache.BucketEntry

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

BucketCache.SharedMemoryBucketEntry, UnsafeSharedMemoryBucketEntry

Enclosing class:

BucketCache

static class BucketCache.BucketEntry
extends Object
implements Serializable

Item in cache. We expect this to be where most memory goes. Java uses 8 bytes just for object headers; after this, we want to use as little as possible - so we only use 8 bytes, but in order to do so we end up messing around with all this Java casting stuff. Offset stored as 5 bytes that make up the long. Doubt we'll see devices this big for ages. Offsets are divided by 256. So 5 bytes gives us 256TB or so.

Field Summary

Fields

Modifier and Type	Field and Description
private long	accessCounter
private long	cachedTime Time this block was cached.
(package private) static Comparator<BucketCache.BucketEntry>	COMPARATOR
(package private) byte	deserialiserIndex
private int	length
private byte	offset1
private int	offsetBase
private BlockPriority	priority
private static long	serialVersionUID

Constructor Summary

Constructors

Constructor and Description
BucketEntry(long offset, int length, long accessCounter, boolean inMemory)

Method Summary

Modifier and Type	Method and Description
void	access(long accessCounter) Block has been accessed.
protected int	decrementRefCountAndGet()
protected CacheableDeserializer<Cacheable>	deserializerReference(UniqueIndexMap<Integer> deserialiserMap)
long	getCachedTime()
int	getLength()
BlockPriority	getPriority()
protected int	getRefCount()
protected int	incrementRefCountAndGet()
protected boolean	isMarkedForEvict()
protected void	markForEvict()
(package private) long	offset()
protected void	setDeserialiserReference(CacheableDeserializer<Cacheable> deserializer, UniqueIndexMap<Integer> deserialiserMap)
private void	setOffset(long value)

Methods inherited from class java.lang.Object

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

Field Detail

serialVersionUID

private static final long serialVersionUID

See Also:

Constant Field Values

COMPARATOR

static final Comparator<BucketCache.BucketEntry> COMPARATOR

offsetBase

private int offsetBase

length

private int length

offset1

private byte offset1

deserialiserIndex

byte deserialiserIndex

accessCounter

private volatile long accessCounter

priority

private BlockPriority priority

cachedTime

private final long cachedTime

Time this block was cached. Presumes we are created just before we are added to the cache.

Constructor Detail

BucketEntry

BucketEntry(long offset,
            int length,
            long accessCounter,
            boolean inMemory)

Method Detail

offset

long offset()

setOffset

private void setOffset(long value)

getLength

public int getLength()

deserializerReference

protected CacheableDeserializer<Cacheable> deserializerReference(UniqueIndexMap<Integer> deserialiserMap)

setDeserialiserReference

protected void setDeserialiserReference(CacheableDeserializer<Cacheable> deserializer,
                                        UniqueIndexMap<Integer> deserialiserMap)

access

public void access(long accessCounter)

Block has been accessed. Update its local access counter.

getPriority

public BlockPriority getPriority()

getCachedTime

public long getCachedTime()

getRefCount

protected int getRefCount()

incrementRefCountAndGet

protected int incrementRefCountAndGet()

decrementRefCountAndGet

protected int decrementRefCountAndGet()

isMarkedForEvict

protected boolean isMarkedForEvict()

markForEvict

protected void markForEvict()