org.terracotta.offheapstore
Class ReadWriteLockedOffHeapClockCache<K,V>

java.lang.Object
  java.util.AbstractMap<K,V>
      org.terracotta.offheapstore.OffHeapHashMap<K,V>
          org.terracotta.offheapstore.AbstractLockedOffHeapHashMap<K,V>
              org.terracotta.offheapstore.AbstractOffHeapClockCache<K,V>
                  org.terracotta.offheapstore.ReadWriteLockedOffHeapClockCache<K,V>

Type Parameters:

K - the type of keys maintained by this map

V - the type of mapped values

All Implemented Interfaces:

ConcurrentMap<K,V>, ReadWriteLock, Map<K,V>, HashingMap<K,V>, MapInternals, PinnableCache<K,V>, PinnableSegment<K,V>, Segment<K,V>, StorageEngine.Owner

Direct Known Subclasses:

EvictionListeningReadWriteLockedOffHeapClockCache

public class ReadWriteLockedOffHeapClockCache<K,V>
extends AbstractOffHeapClockCache<K,V>

A concurrent-read, exclusive-write off-heap clock cache.

This cache uses one of the unused bits in the off-heap entry's status value to store the clock data. This clock data is racily to updated during read operations. Since clock eviction data resides in the hash-map's table, it is correctly copied across during table resize operations.

The cache uses a regular ReentrantReadWriteLock to provide read/write exclusion/sharing properties.

Author:

Chris Dennis

Nested Class Summary

Nested classes/interfaces inherited from class java.util.AbstractMap

AbstractMap.SimpleEntry<K,V>, AbstractMap.SimpleImmutableEntry<K,V>

Nested classes/interfaces inherited from interface java.util.Map

Map.Entry<K,V>

Field Summary

Fields inherited from class org.terracotta.offheapstore.OffHeapHashMap

ENCODING, ENTRY_BIT_SHIFT, ENTRY_SIZE, hashtable, hashTablePage, KEY_HASHCODE, modCount, removedSlots, reprobeLimit, RESERVED_STATUS_BITS, size, STATUS, STATUS_REMOVED, STATUS_USED, storageEngine, tableSource

Constructor Summary

ReadWriteLockedOffHeapClockCache(PageSource source, boolean tableAllocationsSteal, StorageEngine<? super K,? super V> storageEngine)

ReadWriteLockedOffHeapClockCache(PageSource source, boolean tableAllocationsSteal, StorageEngine<? super K,? super V> storageEngine, int tableSize)

ReadWriteLockedOffHeapClockCache(PageSource source, StorageEngine<? super K,? super V> storageEngine)

ReadWriteLockedOffHeapClockCache(PageSource source, StorageEngine<? super K,? super V> storageEngine, int tableSize)

Method Summary

ReentrantReadWriteLock	getLock() Return the ReentrantReadWriteLock used by this segment.
Lock	readLock()
Lock	writeLock()

Methods inherited from class org.terracotta.offheapstore.AbstractOffHeapClockCache

evict, evictable, getAndPin, getEvictionIndex, hit, isPinned, putPinned, setPinning, storageEngineFailure, tableExpansionFailure

Methods inherited from class org.terracotta.offheapstore.AbstractLockedOffHeapHashMap

clear, computeIfAbsentWithMetadata, computeIfPresentWithMetadata, computeWithMetadata, containsKey, destroy, entrySet, fill, fill, get, getAndSetMetadata, getEncodingForHashAndBinary, getMetadata, getValueAndSetMetadata, installMappingForHashAndEncoding, keySet, put, put, putIfAbsent, remove, remove, removeAllWithHash, removeMapping, removeNoReturn, replace, replace, shrink, size, values

Methods inherited from class org.terracotta.offheapstore.OffHeapHashMap

added, encodingSet, fill, freePendingTables, getAllocatedMemory, getAtTableOffset, getDataAllocatedMemory, getDataOccupiedMemory, getDataSize, getDataVitalMemory, getEntryAtTableOffset, getOccupiedMemory, getRemovedSlotCount, getReprobeLength, getSize, getSlotForHashAndEncoding, getStorageEngine, getTableCapacity, getUsedSlotCount, getVitalMemory, indexFor, indexFor, isAvailable, isPresent, isRemoved, isRemoved, isTerminating, isTerminating, isThiefForTableAllocations, readLong, readLong, removeAtTableOffset, removed, shrinkTable, spread, tryIncreaseReprobe, updated, updateEncoding

Methods inherited from class java.util.AbstractMap

clone, containsValue, equals, hashCode, isEmpty, putAll, toString

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.terracotta.offheapstore.Segment

computeIfAbsentWithMetadata, computeIfPresentWithMetadata, computeWithMetadata, destroy, fill, fill, getAndSetMetadata, getMetadata, getValueAndSetMetadata, put, removeNoReturn, shrink

Methods inherited from interface org.terracotta.offheapstore.MapInternals

getAllocatedMemory, getDataAllocatedMemory, getDataOccupiedMemory, getDataSize, getDataVitalMemory, getOccupiedMemory, getRemovedSlotCount, getReprobeLength, getSize, getTableCapacity, getUsedSlotCount, getVitalMemory

Methods inherited from interface org.terracotta.offheapstore.HashingMap

removeAllWithHash

Methods inherited from interface java.util.concurrent.ConcurrentMap

putIfAbsent, remove, replace, replace

Methods inherited from interface java.util.Map

clear, containsKey, containsValue, entrySet, equals, get, hashCode, isEmpty, keySet, put, putAll, remove, size, values

Constructor Detail

ReadWriteLockedOffHeapClockCache

public ReadWriteLockedOffHeapClockCache(PageSource source,
                                        StorageEngine<? super K,? super V> storageEngine)

ReadWriteLockedOffHeapClockCache

public ReadWriteLockedOffHeapClockCache(PageSource source,
                                        boolean tableAllocationsSteal,
                                        StorageEngine<? super K,? super V> storageEngine)

ReadWriteLockedOffHeapClockCache

public ReadWriteLockedOffHeapClockCache(PageSource source,
                                        StorageEngine<? super K,? super V> storageEngine,
                                        int tableSize)

ReadWriteLockedOffHeapClockCache

public ReadWriteLockedOffHeapClockCache(PageSource source,
                                        boolean tableAllocationsSteal,
                                        StorageEngine<? super K,? super V> storageEngine,
                                        int tableSize)

Method Detail

readLock

public Lock readLock()

Specified by:

readLock in interface ReadWriteLock

Specified by:

readLock in class AbstractLockedOffHeapHashMap<K,V>

writeLock

public Lock writeLock()

Specified by:

writeLock in interface ReadWriteLock

Specified by:

writeLock in class AbstractLockedOffHeapHashMap<K,V>

getLock

public ReentrantReadWriteLock getLock()

Description copied from interface: Segment

Return the ReentrantReadWriteLock used by this segment.

Returns:

RRWL for this segment