org.jupiter.common.concurrent.collection

类 ConcurrentAutoTable

java.lang.Object

org.jupiter.common.concurrent.collection.ConcurrentAutoTable

所有已实现的接口:

Serializable

public class ConcurrentAutoTable
extends Object
implements Serializable

An auto-resizing table of longs, supporting low-contention CAS operations. Updates are done with CAS's to no particular table element. The intent is to support highly scalable counters, r/w locks, and other structures where the updates are associative, loss-free (no-brainer), and otherwise happen at such a high volume that the cache contention for CAS'ing a single word is unacceptable.

从以下版本开始:

1.5 Forked from JCTools.

作者:

Cliff Click

另请参阅:

序列化表格

构造器概要

构造器

构造器和说明
ConcurrentAutoTable()

方法概要

方法

限定符和类型	方法和说明
void	add(long x) Add the given value to current counter value.
void	decrement() add(long) with -1
long	estimate_get() A cheaper get().
long	get() Current value of the counter.
void	increment() add(long) with +1
int	internal_size() Return the internal counter striping factor.
int	intValue() Same as get(), included for completeness.
long	longValue() Same as get(), included for completeness.
void	print() A more verbose print than toString(), showing internal structure.
void	set(long x) Atomically set the sum of the striped counters to specified value.
String	toString() Return the counter's long value converted to a string.

从类继承的方法 java.lang.Object

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

构造器详细资料

ConcurrentAutoTable

public ConcurrentAutoTable()

方法详细资料

add

public void add(long x)

Add the given value to current counter value. Concurrent updates will not be lost, but addAndGet or getAndAdd are not implemented because the total counter value (i.e., get()) is not atomically updated. Updates are striped across an array of counters to avoid cache contention and has been tested with performance scaling linearly up to 768 CPUs.

decrement

public void decrement()

add(long) with -1

increment

public void increment()

add(long) with +1

set

public void set(long x)

Atomically set the sum of the striped counters to specified value. Rather more expensive than a simple store, in order to remain atomic.

get

public long get()

Current value of the counter. Since other threads are updating furiously the value is only approximate, but it includes all counts made by the current thread. Requires a pass over the internally striped counters.

intValue

public int intValue()

Same as get(), included for completeness.

longValue

public long longValue()

Same as get(), included for completeness.

estimate_get

public long estimate_get()

A cheaper get(). Updated only once/millisecond, but as fast as a simple load instruction when not updating.

toString

public String toString()

Return the counter's long value converted to a string.

覆盖:

toString 在类中 Object

print

public void print()

A more verbose print than toString(), showing internal structure. Useful for debugging.

internal_size

public int internal_size()

Return the internal counter striping factor. Useful for diagnosing performance problems.