com.neeve.util

Class UtlThread

java.lang.Object

com.neeve.util.UtlThread

public final class UtlThread
extends Object

Utility class containing methods to worh with threads.

This class IS supported for use by end users..

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	UtlThread.ThreadStats Used by a thread to track stats related to its execution.

Constructor Summary

Constructors

Constructor and Description
UtlThread()

Method Summary

Methods

Modifier and Type	Method and Description
static com.lmax.disruptor.SequenceBarrier	asIntrumentedSequenceBarrier(com.lmax.disruptor.SequenceBarrier barrier) Returns a sequence barrier that records disruptor wait times.
static boolean	cpuAffinityMasksEnabled() Returns whether CPU affinitization is enabled or not
static String	decodeAffinityMask(long mask) Returns a mask string for the given mask.
static String	decodeAffinityMask(long mask, boolean physicalFormat) Decodes an affinity mask into a string format.
static void	deregister(Thread thread) Can be called to stop tracking the specified thread.
static void	dumpAffinitizationState(Appendable to, String prefix) Dumps thread affinitization information.
static void	dumpProcessorLayout(Appendable to) Dumps the processor layout to the provided Appendable
static Thread[]	getAllThreads() Gets all running threads in the JVM.
static UtlThread.ThreadStats	getThreadStats(Thread thread) Gets the thread stats for the given thread.
static void	main(String[] args)
static long	parseAffinityMask(String affinity) Parses a mask string into a mask value.
static UtlThread.ThreadStats	registerOrGetThreadStats(Thread thread) Can be called to register a thread for tracking.
static void	setCPUAffinityMask(long mask) Sets the CPU affinity mask of the current thread.
static void	setCPUAffinityMask(String affinity) Sets the CPU affinity mask of the current thread.
static void	setDefaultCPUAffinityMask() Set the CPU affinity mask of the current thread to the default mask
static boolean	threadWaitStatsEnabled() Returns whether thread wait stats are enabled.
static void	triggerThreadDump(Appendable output) Creates a stack dump.

Methods inherited from class java.lang.Object

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

Constructor Detail

UtlThread

public UtlThread()

Method Detail

registerOrGetThreadStats

public static final UtlThread.ThreadStats registerOrGetThreadStats(Thread thread)

Can be called to register a thread for tracking.

The caller should call deregister(Thread) when the thread is longer in use.

Parameters:

thread - The thread to register or null if thread stats are not enabled.

deregister

public static void deregister(Thread thread)

Can be called to stop tracking the specified thread.

Parameters:

thread - The thread to deregister.

cpuAffinityMasksEnabled

public static final boolean cpuAffinityMasksEnabled()

Returns whether CPU affinitization is enabled or not

threadWaitStatsEnabled

public static final boolean threadWaitStatsEnabled()

Returns whether thread wait stats are enabled.

setCPUAffinityMask

public static final void setCPUAffinityMask(long mask)

Sets the CPU affinity mask of the current thread.

Parameters:

mask - The affinity mask to set.

Threading:

This method is safe for concurrent access by multiple threads

setCPUAffinityMask

public static void setCPUAffinityMask(String affinity)

Sets the CPU affinity mask of the current thread.

Parameters:

affinity - The affinity mask to set in the form described by parseAffinityMask(String).

See Also:

parseAffinityMask(String)

Threading:

This method is safe for concurrent access by multiple threads

setDefaultCPUAffinityMask

public static void setDefaultCPUAffinityMask()

Set the CPU affinity mask of the current thread to the default mask

Threading:

This method is safe for concurrent access by multiple threads

parseAffinityMask

public static long parseAffinityMask(String affinity)

Parses a mask string into a mask value. The affinity string can either be a long that represents a mask of logical cpu or a square bracket enclosed comma separated list enumerating the logical cpu

Examples:

• "0" no affinity specified
• "[]" no affinity specified
• "1" specifies logical cpu 0
• "[0]" specifies logical cpu 0
• "4" specifies logical cpu 2
• "[2]" list specifying logical cpu 2
• "6" mask specifying logical cpu 1 and 2
• "4294967296" specifies logical cpu 32
• "[32]" specifies logical cpu 32
• "[1,2]" list specifying logical cpu 1 and 2

Parameters:

affinity - The string describing the affinity mask

Returns:

The affinity mask.

decodeAffinityMask

public static final String decodeAffinityMask(long mask)

Returns a mask string for the given mask.

Parameters:

mask - The mask to decode

Returns:

The mask String in a format that is parsable by parseAffinityMask(String).

decodeAffinityMask

public static final String decodeAffinityMask(long mask,
                        boolean physicalFormat)

Decodes an affinity mask into a string format.

Parameters:

mask - The mask The mask to decode.

physicalFormat - Attempts to resolve the cores to physical format for the given machine,

Returns:

The mask String.

dumpProcessorLayout

public static final void dumpProcessorLayout(Appendable to)

Dumps the processor layout to the provided Appendable

Parameters:

to - The target to which to dump the processor layout.

dumpAffinitizationState

public static final void dumpAffinitizationState(Appendable to,
                           String prefix)

Dumps thread affinitization information.

Parameters:

to - The target to which to dump the affinization state.

getThreadStats

public static final UtlThread.ThreadStats getThreadStats(Thread thread)

Gets the thread stats for the given thread.

Parameters:

thread - The thread for which to retrieve stats.

Returns:

The thread stats (or null if no stats are being tracked for the thread).

See Also:

parseAffinityMask(String)

getAllThreads

public static final Thread[] getAllThreads()

Gets all running threads in the JVM.

This method may be used by end users, but is not supported and is subject to change

Returns:

All running threads, the caller should not modify the returned array.

triggerThreadDump

public static void triggerThreadDump(Appendable output)

Creates a stack dump.

This method may be used by end users, but is not supported and is subject to change

Parameters:

output - the appendable to which to append the dump.

asIntrumentedSequenceBarrier

public static final com.lmax.disruptor.SequenceBarrier asIntrumentedSequenceBarrier(com.lmax.disruptor.SequenceBarrier barrier)

Returns a sequence barrier that records disruptor wait times.

When threadWaitStatsEnabled(), an instrumented SequenceBarrier is returned that records wait times.

This method is intended for internal use only.

Parameters:

barrier - The barrier to instrument.

Returns:

The instrumented barrier.

main

public static final void main(String[] args)