com.aicas.jamaica.lang
Class Scheduler

java.lang.Object
  com.aicas.jamaica.lang.Scheduler

public class Scheduler
extends Object

Scheduler provides access to the Jamaica Scheduler.

Field Summary

static int	ALL_EVENTS_MASK
static int	ALLOCATED_MEMORY The current amount of allocated memory is (hi * 256 + lo) * 65K.
static int	ATOMIC_END End atomic region Arguments
static int	ATOMIC_START Start atomic region Arguments
static int	BLOCKED State for thread that is BLOCKED
static int	CONTINUED Ignore this entry, it is an entry that was combined with the previous one.
static int	CPU_SPEED Indicate measured CPU speed.
static int	DEFAULT_MASK
static int	DETACHABLE State for thread that is RUNNING
static int	DETACHED State for thread that is DETACHED
static int	ENTRY_ALLOCATED_MEMORY_HI optional args for ALLOCATED_MEMORY
static int	ENTRY_ALLOCATED_MEMORY_LO
static int	ENTRY_ARG1
static int	ENTRY_ARG2
static int	ENTRY_CPUSPEED_US_HIGH
static int	ENTRY_CPUSPEED_US_LOW optional args for CPU_SPEED:
static int	ENTRY_GC_PHASE optional args for GC_PHASE
static int	ENTRY_KIND Common entries in each recording:
static int	ENTRY_MONITOR_ID
static int	ENTRY_MONITOR_OWNER optional args for MONITOR_ENTER and MONITOR_EXIT:
static int	ENTRY_PRICHG_BASE_PRI
static int	ENTRY_PRICHG_DYN_PRI optional args for PRIORITY_CHANGE:
static int	ENTRY_RESREQ_RUNNING_THREAD optional args for RESCHEDULE_REQUEST:
static int	ENTRY_RUNNING_ON_CPU_CPU optional args for RUNNING_ON_CPU
static int	ENTRY_SIZE Size of one recording entry, in number of bytes
static int	ENTRY_SLEEPING_THREAD optional args for WAKEUP
static int	ENTRY_STATE_CHANGE_CAUSING_THREAD
static int	ENTRY_STATE_CHANGE_NEW_STATE optional args for STATE_CHANGE:
static int	ENTRY_THREAD
static int	ENTRY_TIME
static int	ENTRY_TIME_LOW
static int	ENTRY_USER_KIND0 optional args for USER
static int	ENTRY_USER_KIND1
static int	GC_PHASE The GC phase change Arguments - GC phase: INIT 1 STOPPED 2 MARK 3 FINALIZE 4 MARK2 5 SWEEP 6
static int	JAMAICA_BLOCK_DUE_TO_COST_OVERRUN Predefined values for reason argument to block() and unblock(): block due to cost overrunt.
static int	JAMAICA_BLOCK_DUE_TO_JVMTI_SUSPEND Predefined values for reason argument to block() and unblock(): block due to suspend request from JVMTI.
static int	JAMAICA_BLOCK_DUE_TO_JVMTI_WAIT_CONNECT Predefined values for reason argument to block() and unblock(): block due to suspend request from JVMTI.
static int	JAMAICA_BLOCK_DUE_TO_MONITOR_ENTER Predefined values for reason argument to block() and unblock(): block due to contention on monitor enter
static int	JAMAICA_BLOCK_DUE_TO_MONITOR_TIMED_WAIT Predefined values for reason argument to block() and unblock(): block due to wait() called on a monitor.
static int	JAMAICA_BLOCK_DUE_TO_MONITOR_WAIT Predefined values for reason argument to block() and unblock(): block due to wait() called on a monitor.
static int	JAMAICA_BLOCK_DUE_TO_STACK_INSPECTION Predefined values for reason argument to block() and unblock(): block due to stack inspection from java.lang.Thread.nativegetStackTraceFor().
static int	JAMAICA_BLOCK_DUE_TO_SUSPEND Predefined values for reason argument to block() and unblock(): block due to Thread.suspend.
static int	JAMAICA_BLOCK_DUE_TO_UNSAFE_PARK Predefined values for reason argument to block() and unblock(): block due to wait() called on a monitor.
static int	JAMAICA_BLOCK_DUE_TO_UNSAFE_TIMED_PARK Predefined values for reason argument to block() and unblock(): block due to wait() called on a monitor.
static int	JAMAICA_BLOCK_DUE_TO_UNUSED Predefined values for reason argument to block() and unblock(): block due to Thread.suspend.
static int	JAMAICA_BLOCK_DUE_TO_VM_INSPECTOR_WAIT_CONNECT Predefined values for reason argument to block() and unblock(): block due to suspend request from VM monitor.
static int	JAMAICA_BLOCK_DUE_TO_VMCI_SUSPEND Predefined values for reason argument to block() and unblock(): block due to suspend request from Virtual Machine Control Interface (VMCI).
static int	JAMAICA_BLOCK_DUE_TO_WAIT_FOR_FINALIZABLE Predefined values for reason argument to block() and unblock(): block due to suspend request from JVMTI.
static int	JAMAICA_BLOCK_DUE_TO_WAIT_FOR_RESERVED_MEMORY Predefined values for reason argument to block() and unblock(): block due to waiting for memory to be allocated by GC such that reserved memory is less than the maximum reserved memory.
static int	JAMAICA_BLOCK_REASONS_UNDEFINED Set of blocking reason flags that are not predefined.
static int	MAX_EVENT_KIND Maximum value of the event kind indicator.
static int	MAX_THREAD_STATE The highest value for a thread state:
static int	MONITOR_CONTENDED Tried to enter a contended monitor Arguments - id of thread that is owning the monitor - id of contended monitor
static int	MONITOR_DETAILED This is an artificial kind, it is never written out.
static int	MONITOR_ENTER Enter a monitor Arguments - id of monitor that is entered
static int	MONITOR_EXIT Exit a monitor Arguments - id of monitor that is exited
static int	NORMAL_STATE_MASK Mask for 'normal' thread states, i.e., all states except RESCHEDULING
static int	OVERFLOW Indicate that the events buffer has overflown Arguments
static int	PRIORITY_CHANGE Priority change of a thread Arguments - the new dynamic priority - the base priority of the thread
static int	READY State for thread that is READY
static int	READY_YIELD A ready thread performs yields the processor.
static int	REQUIRED_EVENTS_MASK
static int	RESCHEDULE A thread performed a reschedule Arguments:
static int	RESCHEDULE_REQUEST A thread requests the running thread to reschedule Arguments: - thread id of running thread
static int	RESCHEDULING State for thread that is RUNNING but needs to be RESCHEDULED
static int	RUNNING State for thread that is RUNNING or DETACHABLE
static int	RUNNING_ON_CPU The given thread is known to run on the given CPU Arguments - number of the CPU it is running on
static int	SET_NAME Set name of a thread Arguments - the name ASCII characters
static int	SET_TIME Set the time of the current entry Arguments - the high 32 bits of the time.
static int	SLEEPING State for thread that is SLEEPING.
static int	START Set the starting point of the recorded data.
static int	START_EXECUTION Indicate that the running thread has obtained the CPU and now starts executing code.
static int	START_GC Start GC work Arguments
static int	STATE_CHANGE The state of a thread has changed.
static int	STOP_GC Finish GC work Arguments
static int	SYNC State value for thread state SYNC.
static int	TERMINATED State for thread that is TERMINATED
static int	UNNORMAL_STATES_SHIFT Bit position at which "unnormal" thread states start, i.e., RESCHEDULING which corresponds to the normal state RUNNING.
static int	USER User event Arguments - the name ASCII characters
static int	WAKEUP Wake up a sleeping blocked thread Arguments - id of thread that is woken up

Constructor Summary

Scheduler()

Method Summary

static void	allocateEventsBuffer(int size) Start recording of scheduling events.
static void	main(String[] args) main the main routine.
static int	microAdjustPriority(int microAdjustment) microAdjustPriority enables to slightly change the priority of the current thread such that it will have precedence over other threads with the same Java priority (+1) or other threads will have priority over this thread (-1), or it will be treated equally (0).
static int	microAdjustPriority(Thread t, int microAdjustment) microAdjustPriority enables to slightly change the priority of a running thread such that it will have precedence over other threads with the same Java priority (+1) or other threads will have priority over this thread (-1), or it will be treated equally (0).
static void	recordUserEvent(int kind, String message) Record a user-defined event with the given message
static void	recordUserEvent(String message) Record a user-defined event with the given message in color white
static int	setMaxIgnorePriority(int pri) setMaxIgnorePriority sets the maximum priority that is to be ignored by the scheduler.
static int	setMaxNonStrictPriority(int pri) setMaxNonStrictPriority sets the maximum non-strict priority.
static void	startRecording(int eventMask) Start recording of scheduling events.
static int	stopRecording() Stop recording of scheduling events.
static void	useStrictPriority(boolean enabled) useStrictPriority forces the scheduler to strictly enforce the current thread's priority, i.e., if a higher priority thread is ready this thread may starve completely even if its priority is less or equal the maximum non-strict priority (@see setMaxNonStrictPriority).
static void	waitOnSocket(int portNum, boolean blocking) Start the events recorder such that it waits for an events recorder connect at the given port.
static void	writeResults(String filename) Write recorded results to a file.
static void	writeResultsQuiet(String filename) Write recorded results to a file.

Methods inherited from class java.lang.Object

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

Field Detail

CONTINUED

public static final int CONTINUED

Ignore this entry, it is an entry that was combined with the previous one.

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Constant Field Values

STATE_CHANGE

public static final int STATE_CHANGE

The state of a thread has changed. Arguments: - new state - blocking mask - thread id of thread causing the change

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RESCHEDULE_REQUEST

public static final int RESCHEDULE_REQUEST

A thread requests the running thread to reschedule Arguments: - thread id of running thread

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RESCHEDULE

public static final int RESCHEDULE

A thread performed a reschedule Arguments:

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READY_YIELD

public static final int READY_YIELD

A ready thread performs yields the processor. Arguments:

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PRIORITY_CHANGE

public static final int PRIORITY_CHANGE

Priority change of a thread Arguments - the new dynamic priority - the base priority of the thread

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CPU_SPEED

public static final int CPU_SPEED

Indicate measured CPU speed. Arguments - low word of ms passed during measurement - high word of ms passed during measurement

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SET_NAME

public static final int SET_NAME

Set name of a thread Arguments - the name ASCII characters

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MONITOR_ENTER

public static final int MONITOR_ENTER

Enter a monitor Arguments - id of monitor that is entered

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MONITOR_EXIT

public static final int MONITOR_EXIT

Exit a monitor Arguments - id of monitor that is exited

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WAKEUP

public static final int WAKEUP

Wake up a sleeping blocked thread Arguments - id of thread that is woken up

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SET_TIME

public static final int SET_TIME

Set the time of the current entry Arguments - the high 32 bits of the time.

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START

public static final int START

Set the starting point of the recorded data. Events before this point are only to set the correct state Arguments

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START_GC

public static final int START_GC

Start GC work Arguments

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STOP_GC

public static final int STOP_GC

Finish GC work Arguments

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START_EXECUTION

public static final int START_EXECUTION

Indicate that the running thread has obtained the CPU and now starts executing code. Arguments

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OVERFLOW

public static final int OVERFLOW

Indicate that the events buffer has overflown Arguments

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USER

public static final int USER

User event Arguments - the name ASCII characters

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MONITOR_CONTENDED

public static final int MONITOR_CONTENDED

Tried to enter a contended monitor Arguments - id of thread that is owning the monitor - id of contended monitor

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RUNNING_ON_CPU

public static final int RUNNING_ON_CPU

The given thread is known to run on the given CPU Arguments - number of the CPU it is running on

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ALLOCATED_MEMORY

public static final int ALLOCATED_MEMORY

The current amount of allocated memory is (hi * 256 + lo) * 65K. Arguments - allocated memory hi - allocated memory lo

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GC_PHASE

public static final int GC_PHASE

The GC phase change Arguments - GC phase: INIT 1 STOPPED 2 MARK 3 FINALIZE 4 MARK2 5 SWEEP 6

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ATOMIC_START

public static final int ATOMIC_START

Start atomic region Arguments

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ATOMIC_END

public static final int ATOMIC_END

End atomic region Arguments

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MAX_EVENT_KIND

public static final int MAX_EVENT_KIND

Maximum value of the event kind indicator.

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MONITOR_DETAILED

public static final int MONITOR_DETAILED

This is an artificial kind, it is never written out. If this is requested, then all MONITOR_ENTER and MONITOR_EXIT will be recorded (except in compiled code), otherwise only those monitor operations that affect several threads will be recorded and the MONITOR_ENTER records may be late. Arguments - id of thread that is woken up

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REQUIRED_EVENTS_MASK

public static final int REQUIRED_EVENTS_MASK

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DEFAULT_MASK

public static final int DEFAULT_MASK

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ALL_EVENTS_MASK

public static final int ALL_EVENTS_MASK

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ENTRY_KIND

public static final int ENTRY_KIND

Common entries in each recording:

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ENTRY_TIME

public static final int ENTRY_TIME

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ENTRY_THREAD

public static final int ENTRY_THREAD

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ENTRY_ARG1

public static final int ENTRY_ARG1

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ENTRY_ARG2

public static final int ENTRY_ARG2

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ENTRY_TIME_LOW

public static final int ENTRY_TIME_LOW

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ENTRY_STATE_CHANGE_NEW_STATE

public static final int ENTRY_STATE_CHANGE_NEW_STATE

optional args for STATE_CHANGE:

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ENTRY_STATE_CHANGE_CAUSING_THREAD

public static final int ENTRY_STATE_CHANGE_CAUSING_THREAD

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ENTRY_RESREQ_RUNNING_THREAD

public static final int ENTRY_RESREQ_RUNNING_THREAD

optional args for RESCHEDULE_REQUEST:

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ENTRY_PRICHG_DYN_PRI

public static final int ENTRY_PRICHG_DYN_PRI

optional args for PRIORITY_CHANGE:

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ENTRY_PRICHG_BASE_PRI

public static final int ENTRY_PRICHG_BASE_PRI

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ENTRY_CPUSPEED_US_LOW

public static final int ENTRY_CPUSPEED_US_LOW

optional args for CPU_SPEED:

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ENTRY_CPUSPEED_US_HIGH

public static final int ENTRY_CPUSPEED_US_HIGH

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ENTRY_MONITOR_OWNER

public static final int ENTRY_MONITOR_OWNER

optional args for MONITOR_ENTER and MONITOR_EXIT:

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ENTRY_MONITOR_ID

public static final int ENTRY_MONITOR_ID

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ENTRY_SLEEPING_THREAD

public static final int ENTRY_SLEEPING_THREAD

optional args for WAKEUP

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ENTRY_USER_KIND0

public static final int ENTRY_USER_KIND0

optional args for USER

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ENTRY_USER_KIND1

public static final int ENTRY_USER_KIND1

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ENTRY_RUNNING_ON_CPU_CPU

public static final int ENTRY_RUNNING_ON_CPU_CPU

optional args for RUNNING_ON_CPU

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ENTRY_ALLOCATED_MEMORY_HI

public static final int ENTRY_ALLOCATED_MEMORY_HI

optional args for ALLOCATED_MEMORY

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ENTRY_ALLOCATED_MEMORY_LO

public static final int ENTRY_ALLOCATED_MEMORY_LO

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ENTRY_GC_PHASE

public static final int ENTRY_GC_PHASE

optional args for GC_PHASE

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ENTRY_SIZE

public static final int ENTRY_SIZE

Size of one recording entry, in number of bytes

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UNNORMAL_STATES_SHIFT

public static final int UNNORMAL_STATES_SHIFT

Bit position at which "unnormal" thread states start, i.e., RESCHEDULING which corresponds to the normal state RUNNING.

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NORMAL_STATE_MASK

public static final int NORMAL_STATE_MASK

Mask for 'normal' thread states, i.e., all states except RESCHEDULING

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RUNNING

public static final int RUNNING

State for thread that is RUNNING or DETACHABLE

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DETACHABLE

public static final int DETACHABLE

State for thread that is RUNNING

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READY

public static final int READY

State for thread that is READY

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BLOCKED

public static final int BLOCKED

State for thread that is BLOCKED

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DETACHED

public static final int DETACHED

State for thread that is DETACHED

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TERMINATED

public static final int TERMINATED

State for thread that is TERMINATED

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SLEEPING

public static final int SLEEPING

State for thread that is SLEEPING. This state is used only for thread state displays in thread monitor to distinguish it from BLOCKED, which does not sleep immediately, and RUNNING, which may be SLEEPING while waiting for another CPU to sync.

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RESCHEDULING

public static final int RESCHEDULING

State for thread that is RUNNING but needs to be RESCHEDULED

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SYNC

public static final int SYNC

State value for thread state SYNC. A thread in state simple sync is RUNNING, but it has to execute a sync point as soon as possible.

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MAX_THREAD_STATE

public static final int MAX_THREAD_STATE

The highest value for a thread state:

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JAMAICA_BLOCK_DUE_TO_UNUSED

public static final int JAMAICA_BLOCK_DUE_TO_UNUSED

Predefined values for reason argument to block() and unblock(): block due to Thread.suspend.

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JAMAICA_BLOCK_DUE_TO_SUSPEND

public static final int JAMAICA_BLOCK_DUE_TO_SUSPEND

Predefined values for reason argument to block() and unblock(): block due to Thread.suspend.

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JAMAICA_BLOCK_DUE_TO_COST_OVERRUN

public static final int JAMAICA_BLOCK_DUE_TO_COST_OVERRUN

Predefined values for reason argument to block() and unblock(): block due to cost overrunt.

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JAMAICA_BLOCK_DUE_TO_MONITOR_ENTER

public static final int JAMAICA_BLOCK_DUE_TO_MONITOR_ENTER

Predefined values for reason argument to block() and unblock(): block due to contention on monitor enter

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JAMAICA_BLOCK_DUE_TO_MONITOR_WAIT

public static final int JAMAICA_BLOCK_DUE_TO_MONITOR_WAIT

Predefined values for reason argument to block() and unblock(): block due to wait() called on a monitor.

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JAMAICA_BLOCK_DUE_TO_WAIT_FOR_FINALIZABLE

public static final int JAMAICA_BLOCK_DUE_TO_WAIT_FOR_FINALIZABLE

Predefined values for reason argument to block() and unblock(): block due to suspend request from JVMTI.

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JAMAICA_BLOCK_DUE_TO_JVMTI_SUSPEND

public static final int JAMAICA_BLOCK_DUE_TO_JVMTI_SUSPEND

Predefined values for reason argument to block() and unblock(): block due to suspend request from JVMTI.

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JAMAICA_BLOCK_DUE_TO_JVMTI_WAIT_CONNECT

public static final int JAMAICA_BLOCK_DUE_TO_JVMTI_WAIT_CONNECT

Predefined values for reason argument to block() and unblock(): block due to suspend request from JVMTI.

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JAMAICA_BLOCK_DUE_TO_VM_INSPECTOR_WAIT_CONNECT

public static final int JAMAICA_BLOCK_DUE_TO_VM_INSPECTOR_WAIT_CONNECT

Predefined values for reason argument to block() and unblock(): block due to suspend request from VM monitor.

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JAMAICA_BLOCK_DUE_TO_VMCI_SUSPEND

public static final int JAMAICA_BLOCK_DUE_TO_VMCI_SUSPEND

Predefined values for reason argument to block() and unblock(): block due to suspend request from Virtual Machine Control Interface (VMCI).

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JAMAICA_BLOCK_DUE_TO_WAIT_FOR_RESERVED_MEMORY

public static final int JAMAICA_BLOCK_DUE_TO_WAIT_FOR_RESERVED_MEMORY

Predefined values for reason argument to block() and unblock(): block due to waiting for memory to be allocated by GC such that reserved memory is less than the maximum reserved memory.

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JAMAICA_BLOCK_DUE_TO_MONITOR_TIMED_WAIT

public static final int JAMAICA_BLOCK_DUE_TO_MONITOR_TIMED_WAIT

Predefined values for reason argument to block() and unblock(): block due to wait() called on a monitor.

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JAMAICA_BLOCK_DUE_TO_UNSAFE_PARK

public static final int JAMAICA_BLOCK_DUE_TO_UNSAFE_PARK

Predefined values for reason argument to block() and unblock(): block due to wait() called on a monitor.

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JAMAICA_BLOCK_DUE_TO_STACK_INSPECTION

public static final int JAMAICA_BLOCK_DUE_TO_STACK_INSPECTION

Predefined values for reason argument to block() and unblock(): block due to stack inspection from java.lang.Thread.nativegetStackTraceFor().

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JAMAICA_BLOCK_DUE_TO_UNSAFE_TIMED_PARK

public static final int JAMAICA_BLOCK_DUE_TO_UNSAFE_TIMED_PARK

Predefined values for reason argument to block() and unblock(): block due to wait() called on a monitor.

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JAMAICA_BLOCK_REASONS_UNDEFINED

public static final int JAMAICA_BLOCK_REASONS_UNDEFINED

Set of blocking reason flags that are not predefined.

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Constructor Detail

Scheduler

public Scheduler()

Method Detail

allocateEventsBuffer

public static void allocateEventsBuffer(int size)

Start recording of scheduling events. If there is a recording in progress, reset the recording.

startRecording

public static void startRecording(int eventMask)

Start recording of scheduling events.

stopRecording

public static int stopRecording()

Stop recording of scheduling events.

Returns:

the number of integers recorded

writeResultsQuiet

public static void writeResultsQuiet(String filename)
                              throws IOException

Write recorded results to a file.

Parameters:

filename - the file to write

Throws:

IOException - if writing failed.

writeResults

public static void writeResults(String filename)

Write recorded results to a file. In case of an IOException, printStackTrace it to stderr.

Parameters:

filename - the file to write

recordUserEvent

public static void recordUserEvent(String message)

Record a user-defined event with the given message in color white

Parameters:

message - the event message, must be a 7-bit ASCII string.

recordUserEvent

public static void recordUserEvent(int kind,
                                   String message)

Record a user-defined event with the given message

Parameters:

kind - an id for this event's kind. This will be used to distinguish different event kinds. Currently, only the lower 16 bits are stored and display tools may use this value modulo some value (e.g. to select a color from a limited set of colors for the display of the event kind).

message - the event message, must be a 7-bit ASCII string.

useStrictPriority

public static void useStrictPriority(boolean enabled)

useStrictPriority forces the scheduler to strictly enforce the current thread's priority, i.e., if a higher priority thread is ready this thread may starve completely even if its priority is less or equal the maximum non-strict priority (@see setMaxNonStrictPriority). Enabling strict priority will enforce higher priority threads to always have priority over this thread. However, if the current thread's priority is less or equal to the maximum non-strict priority, it does not prevent lower priority threads from stealing the current thread's CPU. A typical application of the strict priority would be a low-priority service thread that should run without ever disturbing the execution of any other higher-priority thread (e.g., a low-priority garbage collection thread).

Parameters:

enabled - true to enable strict priorities for the current thread, false to disable strict priorities.

setMaxNonStrictPriority

public static int setMaxNonStrictPriority(int pri)

setMaxNonStrictPriority sets the maximum non-strict priority. Threads that have a Java priority that is less or equal to this priority will not use strict precedence, i.e., none of these threads will starve, even if a higher priority thread is always ready. Only if a thread with a priority higher than the maximum non-strict priority is ready to run, all threads with lower priority may starve.

Parameters:

pri - the new maximum non-strict priority. -1 to keep the maximum non-strict priority unchanged, 0 to disable non-strict priorities, 10 to enable non-strict priorities for normal Java threads only, javax.realtime.PriorityScheduler.getMaxPriority() to enable non-strict priorities for all RTSJ threads (not recommended since this will break the priority scheduling required for realtime code).

Returns:

the previous value for the maximum non strict priority.

setMaxIgnorePriority

public static int setMaxIgnorePriority(int pri)

setMaxIgnorePriority sets the maximum priority that is to be ignored by the scheduler. All Java threads with a priority less or equal to this priority will be treated equally.

Parameters:

pri - the new maximum priority to be ignored. -1 to keep the maximum ignored priority unchanged, 0 to disable ignoring priorities, 10 to treat all normal Java threads equal, javax.realtime.PriorityScheduler.getMaxPriority() to also treat RTSJ threads equally (not recommended since this will break the priority scheduling required for realtime code).

Returns:

the previous value for the maximum ignored priority.

microAdjustPriority

public static int microAdjustPriority(int microAdjustment)

microAdjustPriority enables to slightly change the priority of the current thread such that it will have precedence over other threads with the same Java priority (+1) or other threads will have priority over this thread (-1), or it will be treated equally (0).

Parameters:

microAdjustment - the priority micro adjustment. +1 to slightly increase the priority, -1 to decrease it and 0 to treat this thread equal to other threads with the same Java priority.

Returns:

the previous value for the priority micro adjustement.

microAdjustPriority

public static int microAdjustPriority(Thread t,
                                      int microAdjustment)

microAdjustPriority enables to slightly change the priority of a running thread such that it will have precedence over other threads with the same Java priority (+1) or other threads will have priority over this thread (-1), or it will be treated equally (0). This call will have no effect if the given thread t has not been started yet or has died already.

Parameters:

t - the thread whose priority micro-adjustment is to be changed.

microAdjustment - the priority micro adjustment. +1 to slightly increase the priority, -1 to decrease it and 0 to treat this thread equal to other threads with the same Java priority.

Returns:

the previous value for the priority micro adjustement. Result is Integer.MIN_VALUE in case t is not alive.

waitOnSocket

public static void waitOnSocket(int portNum,
                                boolean blocking)

Start the events recorder such that it waits for an events recorder connect at the given port.

main

public static void main(String[] args)

main the main routine.

Parameters:

args - the arguments array, must be at least of length 1. args[0] is the main class name, args[1..args.length-1] are the arguments to the main class' main() routine.