RuntimeMeasurements (Jikes RVM API)

java.lang.Object
- org.jikesrvm.adaptive.measurements.RuntimeMeasurements

```
public abstract class RuntimeMeasurements
extends Object
```
RuntimeMeasurements manages listeners, decayable objects, and reportable objects.
A listener is installed by an organizer, and activated at thread switch time by Thread. Depending on the update method that the listener supports, it can be either a method, context, or a null listener. Currently we have different registries for different listeners. An alternative design is to have one register with where entries are tagged.
A decayable object implements the Decayable interface. Anyone can register a decayable object, The DecayOrganizer periodically decays all objects that have been registers.
A reportable object implements the Reportable interface, and is typically registered and used by the instrumentation subsystem. A Reporable can be reset and reported.

Field Summary

Fields
Modifier and Type	Field and Description
`private static ContextListener[]`	`cbsContextListeners` context listeners that trigger on CBS call yieldpoints
`private static MethodListener[]`	`cbsMethodListeners` method listeners that trigger on CBS Method yieldpoints
`(package private) static int`	`decayEventCounter` Counts the number of decay events
`(package private) static Vector<Decayable>`	`decayObjects` The currently registered decayable objects
`(package private) static Vector<Reportable>`	`reportObjects` The currently registered reportable objects
`private static ContextListener[]`	`timerContextListeners` listeners on timer ticks for contexts
`private static MethodListener[]`	`timerMethodListeners` listeners on timer ticks for methods
`private static NullListener[]`	`timerNullListeners` listeners on timer ticks for nulls

Constructor Summary

Constructors
Constructor and Description

RuntimeMeasurements()

Constructors
Constructor and Description
`RuntimeMeasurements()`

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method and Description
`static void`	`boot()` Called when the VM is booting
`static void`	`decayDecayableObjects()` Decays all registered decayable objects.
`static void`	`installCBSContextListener(ContextListener s)` Install a context listener on CBS ticks
`static void`	`installCBSMethodListener(MethodListener s)` Install a method listener on CBS ticks
`static void`	`installTimerContextListener(ContextListener s)` Install a context listener on timer ticks
`static void`	`installTimerMethodListener(MethodListener s)` Install a method listener on timer ticks
`static void`	`installTimerNullListener(NullListener s)` Install a null listener on timer ticks
`static void`	`registerDecayableObject(Decayable obj)` Registers an object that should be decayed.
`static void`	`registerReportableObject(Reportable obj)` Registers an object that wants to have its report method called whenever RuntimeMeasurements.report is called.
`static void`	`report()` Reports the current state of runtime measurements.
`private static void`	`reportReportableObjects()` Calls `Reportable.report()` on all registered reportable objects.
`static void`	`resetReportableObjects()` Calls `Reportable.reset()` on all registered reportable objects.
`static void`	`stop()` Stop the runtime measurement subsystem
`static void`	`takeCBSCallSample(int whereFrom, Address yieldpointServiceMethodFP)` Called from Thread.yieldpoint when it is time to take a CBS call sample.
`static void`	`takeCBSMethodSample(int whereFrom, Address yieldpointServiceMethodFP)` Called from Thread.yieldpoint when it is time to take a CBS method sample.
`static void`	`takeTimerSample(int whereFrom, Address yieldpointServiceMethodFP)` Called from Thread.yieldpoint every time it is invoked due to a timer interrupt.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - timerMethodListeners
```
private static MethodListener[] timerMethodListeners
```
    listeners on timer ticks for methods
  - timerContextListeners
```
private static ContextListener[] timerContextListeners
```
    listeners on timer ticks for contexts
  - timerNullListeners
```
private static NullListener[] timerNullListeners
```
    listeners on timer ticks for nulls
  - cbsMethodListeners
```
private static MethodListener[] cbsMethodListeners
```
    method listeners that trigger on CBS Method yieldpoints
  - cbsContextListeners
```
private static ContextListener[] cbsContextListeners
```
    context listeners that trigger on CBS call yieldpoints
  - decayObjects
```
static final Vector<Decayable> decayObjects
```
    The currently registered decayable objects
  - decayEventCounter
```
static int decayEventCounter
```
    Counts the number of decay events
  - reportObjects
```
static Vector<Reportable> reportObjects
```
    The currently registered reportable objects
- Constructor Detail
  - RuntimeMeasurements
```
public RuntimeMeasurements()
```
- Method Detail
  - installTimerMethodListener
```
public static void installTimerMethodListener(MethodListener s)
```
    Install a method listener on timer ticks
    
    Parameters:
    
    s - method listener to be installed
  - installTimerContextListener
```
public static void installTimerContextListener(ContextListener s)
```
    Install a context listener on timer ticks
    
    Parameters:
    
    s - context listener to be installed
  - installTimerNullListener
```
public static void installTimerNullListener(NullListener s)
```
    Install a null listener on timer ticks
    
    Parameters:
    
    s - null listener to be installed
  - takeTimerSample
```
public static void takeTimerSample(int whereFrom,
                                   Address yieldpointServiceMethodFP)
```
    Called from Thread.yieldpoint every time it is invoked due to a timer interrupt.
    
    Parameters:
    
    whereFrom - source of the yieldpoint (e.g. backedge)
    
    yieldpointServiceMethodFP - the frame pointer of the service method that is responsible for handling the yieldpoint
  - installCBSMethodListener
```
public static void installCBSMethodListener(MethodListener s)
```
    Install a method listener on CBS ticks
    
    Parameters:
    
    s - method listener to be installed
  - installCBSContextListener
```
public static void installCBSContextListener(ContextListener s)
```
    Install a context listener on CBS ticks
    
    Parameters:
    
    s - context listener to be installed
  - takeCBSMethodSample
```
public static void takeCBSMethodSample(int whereFrom,
                                       Address yieldpointServiceMethodFP)
```
    Called from Thread.yieldpoint when it is time to take a CBS method sample.
    
    Parameters:
    
    whereFrom - source of the yieldpoint (e.g. backedge)
    
    yieldpointServiceMethodFP - the frame pointer of the service method that is responsible for handling the yieldpoint
  - takeCBSCallSample
```
public static void takeCBSCallSample(int whereFrom,
                                     Address yieldpointServiceMethodFP)
```
    Called from Thread.yieldpoint when it is time to take a CBS call sample.
    
    Parameters:
    
    whereFrom - source of the yieldpoint (e.g. backedge)
    
    yieldpointServiceMethodFP - the frame pointer of the service method that is responsible for handling the yieldpoint
  - registerDecayableObject
```
public static void registerDecayableObject(Decayable obj)
```
    Registers an object that should be decayed. The passed object will have its decay method called when the decaying thread decides it is time for the system to decay.
    
    Parameters:
    
    obj - the object to decay
  - decayDecayableObjects
```
public static void decayDecayableObjects()
```
    Decays all registered decayable objects.
  - registerReportableObject
```
public static void registerReportableObject(Reportable obj)
```
    Registers an object that wants to have its report method called whenever RuntimeMeasurements.report is called.
    
    Parameters:
    
    obj - the object to report about
  - resetReportableObjects
```
public static void resetReportableObjects()
```
    Calls Reportable.reset() on all registered reportable objects.
  - reportReportableObjects
```
private static void reportReportableObjects()
```
    Calls Reportable.report() on all registered reportable objects.
  - report
```
public static void report()
```
    Reports the current state of runtime measurements.
  - stop
```
public static void stop()
```
    Stop the runtime measurement subsystem
  - boot
```
public static void boot()
```
    Called when the VM is booting

Class RuntimeMeasurements

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

timerMethodListeners

timerContextListeners

timerNullListeners

cbsMethodListeners

cbsContextListeners

decayObjects

decayEventCounter

reportObjects

Constructor Detail

RuntimeMeasurements

Method Detail

installTimerMethodListener

installTimerContextListener

installTimerNullListener

takeTimerSample

installCBSMethodListener

installCBSContextListener

takeCBSMethodSample

takeCBSCallSample

registerDecayableObject

decayDecayableObjects

registerReportableObject

resetReportableObjects

reportReportableObjects

report

stop

boot