Package io.netty.util.concurrent

Class FastThreadLocalThread

java.lang.Object

java.lang.Thread

io.netty.util.concurrent.FastThreadLocalThread

All Implemented Interfaces:

java.lang.Runnable

public class FastThreadLocalThread
extends java.lang.Thread

A special Thread that provides fast access to FastThreadLocal variables.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
private static class	FastThreadLocalThread.FallbackThreadSet	Immutable, thread-safe helper class that wraps LongLongHashMap

Nested classes/interfaces inherited from class java.lang.Thread

java.lang.Thread.State, java.lang.Thread.UncaughtExceptionHandler

Field Summary

Fields

Modifier and Type	Field	Description
private boolean	cleanupFastThreadLocals
private static java.util.concurrent.atomic.AtomicReference<FastThreadLocalThread.FallbackThreadSet>	fallbackThreads	Set of thread IDs that are treated like FastThreadLocalThread.
private static InternalLogger	logger
private InternalThreadLocalMap	threadLocalMap

Fields inherited from class java.lang.Thread

MAX_PRIORITY, MIN_PRIORITY, NORM_PRIORITY

Constructor Summary

Constructors

Constructor	Description
FastThreadLocalThread()
FastThreadLocalThread(java.lang.Runnable target)
FastThreadLocalThread(java.lang.Runnable target, java.lang.String name)
FastThreadLocalThread(java.lang.String name)
FastThreadLocalThread(java.lang.ThreadGroup group, java.lang.Runnable target)
FastThreadLocalThread(java.lang.ThreadGroup group, java.lang.Runnable target, java.lang.String name)
FastThreadLocalThread(java.lang.ThreadGroup group, java.lang.Runnable target, java.lang.String name, long stackSize)
FastThreadLocalThread(java.lang.ThreadGroup group, java.lang.String name)

Method Summary

Modifier and Type	Method	Description
static boolean	currentThreadHasFastThreadLocal()	Returns true if this thread supports FastThreadLocal.
static boolean	currentThreadWillCleanupFastThreadLocals()	Returns true if FastThreadLocal.removeAll() will be called once Thread.run() completes.
private static boolean	isFastThreadLocalVirtualThread()
boolean	permitBlockingCalls()	Query whether this thread is allowed to perform blocking calls or not.
static void	runWithFastThreadLocal(java.lang.Runnable runnable)	Run the given task with FastThreadLocal support.
void	setThreadLocalMap(InternalThreadLocalMap threadLocalMap)	Sets the internal data structure that keeps the thread-local variables bound to this thread.
InternalThreadLocalMap	threadLocalMap()	Returns the internal data structure that keeps the thread-local variables bound to this thread.
boolean	willCleanupFastThreadLocals()	Deprecated. Use currentThreadWillCleanupFastThreadLocals() instead
static boolean	willCleanupFastThreadLocals(java.lang.Thread thread)	Deprecated. Use currentThreadWillCleanupFastThreadLocals() instead

Methods inherited from class java.lang.Thread

activeCount, checkAccess, clone, countStackFrames, currentThread, destroy, dumpStack, enumerate, getAllStackTraces, getContextClassLoader, getDefaultUncaughtExceptionHandler, getId, getName, getPriority, getStackTrace, getState, getThreadGroup, getUncaughtExceptionHandler, holdsLock, interrupt, interrupted, isAlive, isDaemon, isInterrupted, join, join, join, resume, run, setContextClassLoader, setDaemon, setDefaultUncaughtExceptionHandler, setName, setPriority, setUncaughtExceptionHandler, sleep, sleep, start, stop, stop, suspend, toString, yield

Methods inherited from class java.lang.Object

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

Field Detail

logger

private static final InternalLogger logger

fallbackThreads

private static final java.util.concurrent.atomic.AtomicReference<FastThreadLocalThread.FallbackThreadSet> fallbackThreads

Set of thread IDs that are treated like FastThreadLocalThread.

cleanupFastThreadLocals

private final boolean cleanupFastThreadLocals

threadLocalMap

private InternalThreadLocalMap threadLocalMap

Constructor Detail

FastThreadLocalThread

public FastThreadLocalThread()

FastThreadLocalThread

public FastThreadLocalThread(java.lang.Runnable target)

FastThreadLocalThread

public FastThreadLocalThread(java.lang.ThreadGroup group,
                             java.lang.Runnable target)

FastThreadLocalThread

public FastThreadLocalThread(java.lang.String name)

FastThreadLocalThread

public FastThreadLocalThread(java.lang.ThreadGroup group,
                             java.lang.String name)

FastThreadLocalThread

public FastThreadLocalThread(java.lang.Runnable target,
                             java.lang.String name)

FastThreadLocalThread

public FastThreadLocalThread(java.lang.ThreadGroup group,
                             java.lang.Runnable target,
                             java.lang.String name)

FastThreadLocalThread

public FastThreadLocalThread(java.lang.ThreadGroup group,
                             java.lang.Runnable target,
                             java.lang.String name,
                             long stackSize)

Method Detail

threadLocalMap

public final InternalThreadLocalMap threadLocalMap()

Returns the internal data structure that keeps the thread-local variables bound to this thread. Note that this method is for internal use only, and thus is subject to change at any time.

setThreadLocalMap

public final void setThreadLocalMap(InternalThreadLocalMap threadLocalMap)

Sets the internal data structure that keeps the thread-local variables bound to this thread. Note that this method is for internal use only, and thus is subject to change at any time.

willCleanupFastThreadLocals

@Deprecated
public boolean willCleanupFastThreadLocals()

Deprecated.

Use currentThreadWillCleanupFastThreadLocals() instead

Returns true if FastThreadLocal.removeAll() will be called once Thread.run() completes.

willCleanupFastThreadLocals

@Deprecated
public static boolean willCleanupFastThreadLocals(java.lang.Thread thread)

Deprecated.

Use currentThreadWillCleanupFastThreadLocals() instead

Returns true if FastThreadLocal.removeAll() will be called once Thread.run() completes.

currentThreadWillCleanupFastThreadLocals

public static boolean currentThreadWillCleanupFastThreadLocals()

Returns true if FastThreadLocal.removeAll() will be called once Thread.run() completes.

currentThreadHasFastThreadLocal

public static boolean currentThreadHasFastThreadLocal()

Returns true if this thread supports FastThreadLocal.

isFastThreadLocalVirtualThread

private static boolean isFastThreadLocalVirtualThread()

runWithFastThreadLocal

public static void runWithFastThreadLocal(java.lang.Runnable runnable)

Run the given task with FastThreadLocal support. This call should wrap the runnable for any thread that is long-running enough to make treating it as a FastThreadLocalThread reasonable, but that can't actually extend this class (e.g. because it's a virtual thread). Netty will use optimizations for recyclers and allocators as if this was a FastThreadLocalThread.

This method will clean up any FastThreadLocals at the end, and currentThreadWillCleanupFastThreadLocals() will return true.

At the moment, FastThreadLocal uses normal ThreadLocal as the backing storage here, but in the future this may be replaced with scoped values, if semantics can be preserved and performance is good.

Parameters:

runnable - The task to run

permitBlockingCalls

public boolean permitBlockingCalls()

Query whether this thread is allowed to perform blocking calls or not. FastThreadLocalThreads are often used in event-loops, where blocking calls are forbidden in order to prevent event-loop stalls, so this method returns false by default.

Subclasses of FastThreadLocalThread can override this method if they are not meant to be used for running event-loops.

Returns:

false, unless overridden by a subclass.