org.terracotta.offheapstore.storage.allocator
Class PowerOfTwoAllocator

java.lang.Object
  java.util.AbstractCollection<E>
      java.util.AbstractSet<T>
          org.terracotta.offheapstore.util.AATreeSet<org.terracotta.offheapstore.storage.allocator.Region>
              org.terracotta.offheapstore.storage.allocator.PowerOfTwoAllocator

All Implemented Interfaces:

Iterable<org.terracotta.offheapstore.storage.allocator.Region>, Collection<org.terracotta.offheapstore.storage.allocator.Region>, Set<org.terracotta.offheapstore.storage.allocator.Region>, SortedSet<org.terracotta.offheapstore.storage.allocator.Region>

public class PowerOfTwoAllocator
extends AATreeSet<org.terracotta.offheapstore.storage.allocator.Region>

An augmented AA tree allocator with unusual alignment/allocation properties.

This allocator allocates only power-of-two size chunks. In addition these chunks are then only allocated on alignment with their own size. Hence a chunk of 2ⁿ size can only be allocated to an address satisfying a=2ⁿx where x is an integer.

Author:

Chris Dennis

Nested Class Summary

static class

PowerOfTwoAllocator.Packing

Nested classes/interfaces inherited from class org.terracotta.offheapstore.util.AATreeSet

AATreeSet.AbstractTreeNode<E extends Comparable<? super E>>, AATreeSet.Node<E extends Comparable<? super E>>

Constructor Summary

PowerOfTwoAllocator(int size)
Create a power-of-two allocator with the given initial 'free' size area.

Method Summary

int	allocate(int size, PowerOfTwoAllocator.Packing packing)
void	claim(int address, int size)
int	find(int size, PowerOfTwoAllocator.Packing packing)
org.terracotta.offheapstore.storage.allocator.Region	find(Object o)
void	free(int address, int length)
int	occupied()
org.terracotta.offheapstore.storage.allocator.Region	removeAndReturn(Object o)
String	toString()
void	tryFree(int address, int length)

Methods inherited from class org.terracotta.offheapstore.util.AATreeSet

add, clear, comparator, first, getRoot, headSet, isEmpty, iterator, last, remove, size, subSet, tailSet

Methods inherited from class java.util.AbstractSet

equals, hashCode, removeAll

Methods inherited from class java.util.AbstractCollection

addAll, contains, containsAll, retainAll, toArray, toArray

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Set

addAll, contains, containsAll, equals, hashCode, removeAll, retainAll, toArray, toArray

Constructor Detail

PowerOfTwoAllocator

public PowerOfTwoAllocator(int size)

Create a power-of-two allocator with the given initial 'free' size area.

Parameters:

size - initial free size

Method Detail

allocate

public int allocate(int size,
                    PowerOfTwoAllocator.Packing packing)

free

public void free(int address,
                 int length)

tryFree

public void tryFree(int address,
                    int length)

find

public int find(int size,
                PowerOfTwoAllocator.Packing packing)

claim

public void claim(int address,
                  int size)

occupied

public int occupied()

removeAndReturn

public org.terracotta.offheapstore.storage.allocator.Region removeAndReturn(Object o)

Overrides:

removeAndReturn in class AATreeSet<org.terracotta.offheapstore.storage.allocator.Region>

find

public org.terracotta.offheapstore.storage.allocator.Region find(Object o)

Overrides:

find in class AATreeSet<org.terracotta.offheapstore.storage.allocator.Region>

toString

public String toString()

Overrides:

toString in class AbstractCollection<org.terracotta.offheapstore.storage.allocator.Region>