com.oracle.truffle.tools.profiler

Class HeapMonitor

java.lang.Object

com.oracle.truffle.tools.profiler.HeapMonitor

All Implemented Interfaces:

Closeable, AutoCloseable

public final class HeapMonitor
extends Object
implements Closeable

Implementation of a heap allocation monitor for Truffle languages built on top of the Truffle instrumentation framework.

The HeapMonitor only tracks allocations while the heap monitor is collecting data. This means that allocations that were performed while the heap monitor was not collecting data are not tracked.

Usage example: HeapMonitorSnippets.example()

Since:

19.0

See Also:

HeapMonitor.takeSummary(), HeapMonitor.takeMetaObjectSummary()

Method Summary

Modifier and Type	Method and Description
void	clearData() Erases all the data gathered by the HeapMonitor.
void	close() Closes the HeapMonitor for further use, deleting all the gathered data.
static HeapMonitor	find(org.graalvm.polyglot.Engine engine) Returns the HeapMonitor associated with a given engine.
boolean	hasData() Returns true if the HeapMonitor has collected any data, else false.
boolean	isCollecting() Returns true if the heap monitor is collecting data, else false.
void	setCollecting(boolean collecting) Controls whether the HeapMonitor is collecting data or not.
Map<com.oracle.truffle.api.nodes.LanguageInfo,Map<String,HeapSummary>>	takeMetaObjectSummary() Returns a summary of the current state of the heap grouped by language and meta object name.
HeapSummary	takeSummary() Returns a summary of the current state of the heap.

Methods inherited from class java.lang.Object

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

Method Detail

find

public static HeapMonitor find(org.graalvm.polyglot.Engine engine)

Returns the HeapMonitor associated with a given engine.

Parameters:

engine - the engine to find debugger for

Returns:

an instance of associated HeapMonitor

Since:

19.0

setCollecting

public void setCollecting(boolean collecting)

Controls whether the HeapMonitor is collecting data or not.

Parameters:

collecting - the new state of the monitor.

Throws:

IllegalStateException - if the heap monitor was already closed

Since:

19.0

isCollecting

public boolean isCollecting()

Returns true if the heap monitor is collecting data, else false.

Since:

19.0

takeSummary

public HeapSummary takeSummary()

Returns a summary of the current state of the heap.

The HeapMonitor only tracks allocations while the heap monitor is collecting data. This means that allocations that were performed while the heap monitor was not collecting data are not tracked.

Throws:

IllegalStateException - if the heap monitor was already closed

Since:

19.0

takeMetaObjectSummary

public Map<com.oracle.truffle.api.nodes.LanguageInfo,Map<String,HeapSummary>> takeMetaObjectSummary()

Returns a summary of the current state of the heap grouped by language and meta object name.

The HeapMonitor only tracks allocations while the heap monitor is collecting data. This means that allocations that were performed while the heap monitor was not collecting are ignored. In other words the HeapMonitor reports snapshots as if the heap was completely empty when it was "enabled".

Throws:

IllegalStateException - if the heap monitor was already closed

Since:

19.0

clearData

public void clearData()

Erases all the data gathered by the HeapMonitor.

Since:

19.0

hasData

public boolean hasData()

Returns true if the HeapMonitor has collected any data, else false.

Since:

19.0

close

public void close()

Closes the HeapMonitor for further use, deleting all the gathered data.

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Since:

19.0