com.ibm.java.diagnostics.healthcenter.api.vmcontrol

Interface VMControl



  • public interface VMControl
    This class provides methods to trigger events on the virtual machine that is running the monitored application.
    • Method Detail

      • setObjectAllocationsEnabled

        void setObjectAllocationsEnabled(long lowThreshold,
                                         long highThreshold)
        Enables the collection of object allocation data for objects within a specified size range.
        Parameters:
        lowThreshold - the minimum size (in bytes) of the objects to collect data on.
        highThreshold - the maximum size (in bytes) of the objects to collect data on.
      • setObjectAllocationsEnabled

        void setObjectAllocationsEnabled(long lowValue)
        Enables the collection of object allocation data for objects above a specified size.
        Parameters:
        lowValue - the minimum size (in bytes) of the objects to collect data on.
      • setVerboseGCCollectionEnabled

        void setVerboseGCCollectionEnabled(boolean value)
        Turns the writing of verbose garbage collection data to a file on or off. The name of the file that is created is verbosegc_process_id_n.log, where process_id is the process ID of the monitored JVM, and n is a sequence number. The file is saved in a directory that is local to the monitored JVM specified by the com.ibm.java.diagnostics.healthcenter.output.folder property. If this property is not set, the file is saved in the directory that is specified by the user.dir system property.
        Parameters:
        value - whether collection is on or off. *
      • triggerHeapDump

        boolean triggerHeapDump()
        Triggers a heap dump in the running virtual machine. A heap dump provides a view of memory objects on the Java heap, and is used for memory analysis.
        Returns:
        true if the trigger command was successfully sent to the virtual machine, false if the command failed.
      • triggerSystemDump

        boolean triggerSystemDump()
        Triggers a system dump in the running virtual machine. A system dump is also known as a core dump. System dump creation involves dumping the entire address space, and can therefore produce very large dumps, and take some time to complete.
        Returns:
        true if the trigger command was successfully sent to the virtual machine, false if the command failed.
      • triggerJavaDump

        boolean triggerJavaDump()
        Triggers a Java dump in the running virtual machine. A Java dump is also known as a thread dump of the Java core. The Java dump is used for viewing the thread activity inside the JVM at a given time.
        Returns:
        true if the trigger command was successfully sent to the virtual machine, false if the command failed.
      • setCallStackCollectionEnabled

        void setCallStackCollectionEnabled(boolean value)
        Enables the collection of call stacks for sampled object allocation events.
        Parameters:
        value - whether the collection is on or off.
      • setMaxStackDepth

        void setMaxStackDepth(int depth)
        Sets the maximum number of stack entries to collect for each event.
        Parameters:
        depth - the maximum number of stack entries.
      • setGCDataCollectionEnabled

        void setGCDataCollectionEnabled(boolean value)
        Turns GC data collection on or off. By default, GC data collection is on. Turning this data off can reduce the amount of data generated by the virtual machine that is running the monitored application, and as a result, can reduce the overhead of monitoring an application with the Health Center.
        Parameters:
        value - whether the collection is on or off.
      • setIODataCollectionEnabled

        void setIODataCollectionEnabled(boolean value)
        Turns IO data collection on or off. By default, IO data collection is on. Turning this data off can reduce the amount of data generated by the virtual machine that is running the monitored application, and as a result, can reduce the overhead of monitoring an application with the Health Center.
        Parameters:
        value - whether the collection is on or off.
      • setClassesDataCollectionEnabled

        void setClassesDataCollectionEnabled(boolean value)
        Turns classes data collection on or off. By default, classes data collection is on. Turning this data off can reduce the amount of data generated by the virtual machine that is running the monitored application, and as a result, can reduce the overhead of monitoring an application with the Health Center.
        Parameters:
        value - whether the collection is on or off.
      • setLockingDataCollectionEnabled

        void setLockingDataCollectionEnabled(boolean value)
        Turns locking data collection on or off. By default, locking data collection is on. Turning this data off can reduce the amount of data generated by the virtual machine that is running the monitored application, and as a result, can reduce the overhead of monitoring an application with the Health Center.
        Parameters:
        value - whether the collection is on or off.
      • setNativeMemoryDataCollectionEnabled

        void setNativeMemoryDataCollectionEnabled(boolean value)
        Turns native memory data collection on or off. By default, native memory data collection is on. Turning this data off can reduce the amount of data generated by the virtual machine that is running the monitored application, and as a result, can reduce the overhead of monitoring an application with the Health Center.
        Parameters:
        value - whether the collection is on or off.
      • setProfilingDataCollectionEnabled

        void setProfilingDataCollectionEnabled(boolean value)
        Turns profiling data collection on or off. By default, profiling data collection is on. Turning this data off can reduce the amount of data generated by the virtual machine that is running the monitored application, and as a result, can reduce the overhead of monitoring an application with the Health Center.
        Parameters:
        value - whether the collection is on or off.
      • setThreadDataCollectionEnabled

        void setThreadDataCollectionEnabled(boolean value)
        Turns thread data collection on or off. By default, thread data collection is on. Turning this data off can reduce the amount of data generated by the virtual machine that is running the monitored application, and as a result, can reduce the overhead of monitoring an application with the Health Center.
        Parameters:
        value - whether the collection is on or off.
      • setThreadStackDepth

        void setThreadStackDepth(int depth)
        Sets the maximum number of stack entries to collect for each thread. Setting this to zero will turn off thread stack collection.
        Parameters:
        depth - the maximum number of stack entries required.
      • setTracePointEnabled

        void setTracePointEnabled(java.lang.String tracePointID,
                                  boolean value)
                           throws HealthCenterException
        Turns individual trace points on or off.
        Parameters:
        tracePointID - the ID of the trace point to enable or disable.
        value - whether the trace point is on or off.
        Throws:
        HealthCenterException - if the call is unsuccessful.
      • isGCDataCollectionEnabled

        boolean isGCDataCollectionEnabled()
        Returns whether GC data collection is enabled.
        Returns:
        boolean.
      • isIODataCollectionEnabled

        boolean isIODataCollectionEnabled()
        Returns whether IO data collection is enabled.
        Returns:
        boolean.
      • isProfilingDataCollectionEnabled

        boolean isProfilingDataCollectionEnabled()
        Returns whether profiling data collection is enabled.
        Returns:
        boolean.
      • isClassesDataCollectionEnabled

        boolean isClassesDataCollectionEnabled()
        Returns whether classes data collection is enabled.
        Returns:
        boolean.
      • isThreadsDataCollectionEnabled

        boolean isThreadsDataCollectionEnabled()
        Returns whether threads data collection is enabled.
        Returns:
        boolean.
      • isNativeMemoryDataCollectionEnabled

        boolean isNativeMemoryDataCollectionEnabled()
        Returns whether native memory data collection is enabled.
        Returns:
        boolean.
      • isLockingDataCollectionEnabled

        boolean isLockingDataCollectionEnabled()
        Returns whether locking data collection is enabled.
        Returns:
        boolean.
      • collectClassHistogramData

        void collectClassHistogramData()
                                throws HealthCenterNotSupportedException
        Triggers the collection of the class histogram data. For every class loaded, this process collects the number of instances of that class, and the total amount of memory that is used by those instances.
        Throws:
        HealthCenterNotSupportedException.
        HealthCenterNotSupportedException
© Copyright 2012, 2016 IBM Corporation.