org.graalvm.collections

Class LockFreePrefixTree.ObjectPoolingAllocator

java.lang.Object

org.graalvm.collections.LockFreePrefixTree.Allocator

org.graalvm.collections.LockFreePrefixTree.ObjectPoolingAllocator

Enclosing class:

LockFreePrefixTree

public static class LockFreePrefixTree.ObjectPoolingAllocator
extends LockFreePrefixTree.Allocator

Allocator that internally maintains several pools of preallocated objects, and allocates objects from those pools. This allocator is guaranteed not to allocate any objects inside the invocations to its methods. To ensure that the internal pools have sufficiently many preallocated objects, this allocator has a housekeeping thread that periodically wakes up, allocates objects and inserts them into the pools. This allocator tracks the requests that failed since the last housekeeping session, and the housekeeping thread will strive to accomodate requests that have not been fulfilled since the last housekeeping session (i.e. it will preallocate those types of additional objects whose allocation request previously failed, and it will allocate at least as many objects as there were previous failed allocation requests). This implementation only allows allocating Node.LinearChildren and Node.HashChildren arrays whose length is a power of 2 (because LockFreePrefixTree only ever allocates arrays that are a power of 2). If the requested array length is not a power of 2, an exception is thrown.

Since:

23.0

Constructor Summary

Constructors

Constructor and Description
ObjectPoolingAllocator()
ObjectPoolingAllocator(int housekeepingPeriodMillis)

Method Summary

Modifier and Type	Method and Description
org.graalvm.collections.LockFreePrefixTree.Node.HashChildren	newHashChildren(int length) Allocates a new reference array of child nodes stored as a hash table.
org.graalvm.collections.LockFreePrefixTree.Node.LinearChildren	newLinearChildren(int length) Allocates a new reference array of child nodes stored linearly.
LockFreePrefixTree.Node	newNode(long key) Allocates a new Node object.
void	shutdown() Releases the allocator's resources.
String	status()

Methods inherited from class java.lang.Object

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

Constructor Detail

ObjectPoolingAllocator

public ObjectPoolingAllocator()

ObjectPoolingAllocator

public ObjectPoolingAllocator(int housekeepingPeriodMillis)

Method Detail

newNode

public LockFreePrefixTree.Node newNode(long key)

Description copied from class: LockFreePrefixTree.Allocator

Allocates a new Node object.

Specified by:

newNode in class LockFreePrefixTree.Allocator

Parameters:

key - The key to use for the Node object.

Returns:

A fresh Node object, possibly preallocated.

newLinearChildren

public org.graalvm.collections.LockFreePrefixTree.Node.LinearChildren newLinearChildren(int length)

Description copied from class: LockFreePrefixTree.Allocator

Allocates a new reference array of child nodes stored linearly.

Specified by:

newLinearChildren in class LockFreePrefixTree.Allocator

Parameters:

length - The length of the allocated array.

Returns:

A fresh array, possibly preallocated.

newHashChildren

public org.graalvm.collections.LockFreePrefixTree.Node.HashChildren newHashChildren(int length)

Description copied from class: LockFreePrefixTree.Allocator

Allocates a new reference array of child nodes stored as a hash table.

Specified by:

newHashChildren in class LockFreePrefixTree.Allocator

Parameters:

length - The length of the allocated array.

Returns:

A fresh array, possibly preallocated.

shutdown

public void shutdown()

Description copied from class: LockFreePrefixTree.Allocator

Releases the allocator's resources. Allocator should not be used after calling this method.

Specified by:

shutdown in class LockFreePrefixTree.Allocator

status

public String status()