GCDetails (Zing MXBeans)

java.lang.Object
- com.azul.zing.management.GCDetails

```
public class GCDetails
extends java.lang.Object
```
A snapshot of the details of the JVM environment before and after a garbage collection. For each collection, the GCDetails contains the important information about the JVM state and the garbage collector’s behavior. The following are the categories and the information available.
Collection identifier and cause information
isValidData()
getId()
getGarbageCollectionMinorMajorTotalCount()
getGarbageCollectionType()
getGarbageCollectionCause()
Zing Java heap memory used by the process
getPeakJavaHeapUsedSinceEndOfPreviousCollection()
getMaximumMemoryAvailableForJVMsJavaHeap()
Generation metrics
getLiveInGeneration()
getGarbageFound()
getGarbageCollected()
getFragmentedSpaceInGeneration()
Collection’s time metrics
getPercentageOfTimeCollectorIsRunning()
getStartTime()
getEndTime()
getTimeFromEndOfPreviousToStart()
getCollectionDuration()
Process’s pause prevention memory use
getPeakPausePreventionMemoryUsedSinceEndOfPreviousCollection()
getUnreturnedPausePreventionMemory()
isAbleToUsePausePreventionMemory()
getHasPausePreventionMemoryBeenUsedSinceEndOfPreviousCollection()
getHasRequestForPausePreventionMemoryFailedSinceEndOfPreviousCollection()
Process’s contingency memory use
isAbleToUseContingencyMemory()
getHasContingencyMemoryBeenUsedSinceEndOfPreviousCollection()
Allocation rates
getAllocationRateDuringCollection()
getAllocationRateBetweenEndOfPreviousAndStart()
getPermAllocationRateDuringCollection()
getPermAllocationRateBetweenEndOfPreviousAndStart()
Garbage Collector threads
getGarbageCollectorThreadCount()
Application threads and whether any have been delayed while allocating
getTotalApplicationThreadCount()
getNumberOfApplicationThreadsDelayed()
getAverageApplicationThreadDelay()
getMaximumApplicationThreadDelay()
Page information
getSidebandMemoryUse()
getPromotedPages()
getRelocatedPages()
getNoRelocatePages()
getRelocSpikePages()
getSmallSpacePages()
getMidSpacePages()
getLargeSpacePages()
Compilers enabled
getCompilersEnabled()
Pause times for each of the pauses required during this collection
collectorRequiredPauseDetails returns a List<PauseDetails> object
Maximum pause times for each of the pauses required during the collection
collectorRequiredMaxPauseDetails returns a List<PauseDetails> object
Memory usage for each memoory pool at start of this garbage collection
memoryUsageAtStartOfGC returns a Map<String, MemoryUsage> object
Memory usage for each memoory pool at end of this garbage collection
memoryUsageAtEndOfGC returns a Map<String, MemoryUsage> object

Method Summary

Methods
Modifier and Type	Method and Description
`double`	`getAllocationRateBetweenEndOfPreviousAndStart()` Returns the object allocation rate in units of megabytes per second during the time interval between the end of the last previous collection and start of this garbage collection for the garbage collector of this type.
`double`	`getAllocationRateDuringCollection()` Returns the object allocation rate in units of megabytes per second during the time interval between the beginning and end of this garbage collection for this type of garbage collector.
`double`	`getAverageApplicationThreadDelay()` Returns the average pause time in seconds for all of the application threads that were required to pause waiting for object allocation in the interval between the end of the previous collection and the end of this collection for this garbage collector.
`double`	`getCollectionDuration()` Elapsed time in seconds (also called wall clock time) between the start of this garbage collection and the end of this garbage collection for which this `GCDetails` object was generated.
`java.util.List<PauseDetails>`	`getCollectorRequiredMaxPauseDetails()` Returns a `List` of the maximum `PauseDetails` for each of the pauses required during the garbage collection for this garbage collector type.
`java.util.List<PauseDetails>`	`getCollectorRequiredPauseDetails()` Returns a `List` of the `PauseDetails` for each of the pauses required during the garbage collection for this garbage collector type.
`boolean`	`getCompilersEnabled()` Return whether the JVM’s runtime compiler (JIT) is enabled to compile Java methods to native code.
`double`	`getEndTime()` Returns end time of the garbage collection for this type of collector in units of elapsed seconds since the start of the JVM.
`long`	`getFragmentedSpaceInGeneration()` Returns the approximate difference (in units of bytes) between the size of the generations collected by this garbage collector `getGarbageCollectionType()` and the bytes of live objects returned by `getLiveInGeneration()` for this garbage collector.
`long`	`getGarbageCollected()` Returns the aggregate size of all objects collected by this garbage collector during this garbage collection in units of bytes.
`java.lang.String`	`getGarbageCollectionCause()` Returns the reason that the garbage collector was started for this garbage collection.
`long`	`getGarbageCollectionMinorMajorTotalCount()` A numeric value assigned at the start of this garbage collection: incremented by one prior to assignment for a minor collection (New Generation only); incremented by one prior to assignment for a major collection and used as the count assigned to the New Generation collection before being incremented again and assigned to the Old Generation collection that completes the major (NTO/Old) collection.
`java.lang.String`	`getGarbageCollectionType()` Returns the type of garbage collection for this garbage collection.
`long`	`getGarbageCollectorThreadCount()` Returns the number of garbage collection threads in the pool of garbage collection threads for the garbage collector of this type.
`long`	`getGarbageFound()` Returns the aggregate size of all unreachable objects discovered by this garbage collector during this garbage collection in units of bytes.
`boolean`	`getHasContingencyMemoryBeenUsedSinceEndOfPreviousCollection()` Returns whether the JVM required and was able to use Contingency memory in the interval between the end of the previous collection and the end of this collection for the garbage collector of this type.
`boolean`	`getHasPausePreventionMemoryBeenUsedSinceEndOfPreviousCollection()` Returns whether the JVM required and was able to use Pause Prevention memory in the interval between the end of the previous collection and the end of this collection for the garbage collector of this type.
`boolean`	`getHasRequestForPausePreventionMemoryFailedSinceEndOfPreviousCollection()` Returns whether the JVM’s request for additional Pause Prevention memory failed in the interval between the end of the previous collection and the end of this collection for the garbage collector of this type.
`long`	`getId()` Returns a monotonically increasing number representing the sequence number of this garbage collection performed by this garbage collector.
`long`	`getLargeSpacePages()` Number of pages in the large space, one of three spaces.
`long`	`getLiveInGeneration()` Returns the approximate occupancy by live objects (in units of bytes) of the generations collected by this type of garbage collector (returned by `getGarbageCollectionType()` at the end of this garbage collection.
`double`	`getMaximumApplicationThreadDelay()` Returns the maximum pause time in seconds for all of the application threads that were required to pause waiting for object allocation in the interval between the end of the previous collection and the end of this collection for this garbage collector.
`long`	`getMaximumMemoryAvailableForJVMsJavaHeap()` The total memory available for the JVM process to use for its Java heap including the Initial Reserved memory and any additional memory available from the Java Heap’s parent pool that is available for use by the current process.
`java.util.Map<java.lang.String,MemoryUsage>`	`getMemoryUsageAtEndOfGC()` Returns a `Map` with the `MemoryUsage` for each of the memory pools at the end of the garbage collection for this garbage collector type.
`java.util.Map<java.lang.String,MemoryUsage>`	`getMemoryUsageAtStartOfGC()` Returns a `Map` with the `MemoryUsage` for each of the memory pools at the start of the garbage collection for this garbage collector type.
`long`	`getMidSpacePages()` Number of pages in the mid space, one of three spaces.
`long`	`getNoRelocatePages()` Number of pages not relocated during this garbage collection.
`long`	`getNumberOfApplicationThreadsDelayed()` Returns the number of times application threads were required to pause waiting for object allocation in the interval between the end of the previous collection and the end of this collection for this type of garbage collector.
`long`	`getPeakJavaHeapUsedSinceEndOfPreviousCollection()` For this type of collector, the peak Java heap use between the end of the previous collection and the end of this collection.
`long`	`getPeakPausePreventionMemoryUsedSinceEndOfPreviousCollection()` Returns the peak Pause Prevention memory use between the end of the previous collection and the end of this collection for the garbage collector of this type.
`double`	`getPercentageOfTimeCollectorIsRunning()` For the garbage collector with the type returned by `getGarbageCollectionType()`, the percentage of time in seconds that this garbage collector has been running over the time interval between the end of the last previous collection of this type and the end of this collection.
`double`	`getPermAllocationRateBetweenEndOfPreviousAndStart()` Returns the object allocation rate into the Permanent Generation in units of megabytes per second during the time interval between the end of the last previous collection and start of this collection for this collector type.
`double`	`getPermAllocationRateDuringCollection()` Returns the object allocation rate into the Permanent Generation in units of megabytes per second during the time interval between the beginning and end of this garbage collection for this type of garbage collector.
`long`	`getPromotedPages()` Number of pages promoted from the New Generation to the Old Generation during this garbage collection.
`long`	`getRelocatedPages()` Number of pages relocated during this garbage collection.
`long`	`getRelocSpikePages()` Number of pages relocated that required use of a normally reserved memory area during this garbage collection.
`long`	`getSidebandMemoryUse()` Amount of additional memory used in bytes by the garbage collector during its marking phase.
`long`	`getSmallSpacePages()` Number of pages in the small space, one of three spaces.
`double`	`getStartTime()` Returns start time of this garbage collection in units of elapsed seconds since the start of the JVM.
`double`	`getTimeFromEndOfPreviousToStart()` For the garbage collector with the type returned by `getGarbageCollectionType()`, the amount of time in seconds from the end of the last previous garbage collection for this type of collector to the start of this garbage collection in units of elapsed seconds since the start of the JVM.
`long`	`getTotalApplicationThreadCount()` Returns the number of application threads in the running process.
`long`	`getUnreturnedPausePreventionMemory()` Answers the question whether the JVM’s memory needs are sufficiently high to require continued use of some of the Pause Prevention memory used in the interval between the end of the previous collection and the end of this collection for this collector.
`boolean`	`isAbleToUseContingencyMemory()` Indication of the state of the JVM related to the use of additional memory available from the Java Heap’s parent pool, referred to as Contingency memory.
`boolean`	`isAbleToUsePausePreventionMemory()` Indicates the state of the JVM related to the use of Pause Prevention memory available from the Java Heap’s parent pool.
`boolean`	`isValidData()` Returns whether the data returned `GCDetails` has passed all validity tests.
`java.lang.String`	`toString()` Convert this `GCDetails` object to a `String` representation.

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

- Method Detail
  - getAllocationRateBetweenEndOfPreviousAndStart
```
public double getAllocationRateBetweenEndOfPreviousAndStart()
```
    Returns the object allocation rate in units of megabytes per second during the time interval between the end of the last previous collection and start of this garbage collection for the garbage collector of this type.
    
    Returns:
    the object allocation rate in units of megabytes per second during the time interval between the end of the last previous collection and start of this collection for the garbage collectors of this type.
  - getAllocationRateDuringCollection
```
public double getAllocationRateDuringCollection()
```
    Returns the object allocation rate in units of megabytes per second during the time interval between the beginning and end of this garbage collection for this type of garbage collector.
    
    Returns:
    the object allocation rate in units of megabytes per second during the time interval between the beginning and end of this garbage collection.
  - getAverageApplicationThreadDelay
```
public double getAverageApplicationThreadDelay()
```
    Returns the average pause time in seconds for all of the application threads that were required to pause waiting for object allocation in the interval between the end of the previous collection and the end of this collection for this garbage collector. The application threads should never pause waiting for object allocation and the average returned is expected to always be zero for an application configured and running correctly.
    
    Returns:
    average pause time for all of the application threads that were required to pause waiting for object allocation in the interval between the end of the previous collection and the end of this collection for this collector.
  - getCollectionDuration
```
public double getCollectionDuration()
```
    Elapsed time in seconds (also called wall clock time) between the start of this garbage collection and the end of this garbage collection for which this GCDetails object was generated.
    
    Returns:
    double value representing the elapsed time in seconds between the start and the end of this garbage collection.
  - getCollectorRequiredMaxPauseDetails
```
public java.util.List<PauseDetails> getCollectorRequiredMaxPauseDetails()
```
    Returns a List of the maximum PauseDetails for each of the pauses required during the garbage collection for this garbage collector type.
    
    Returns:
    a List of the maximum PauseDetails for each of the pauses required during the garbage collection for this garbage collector type.
  - getCollectorRequiredPauseDetails
```
public java.util.List<PauseDetails> getCollectorRequiredPauseDetails()
```
    Returns a List of the PauseDetails for each of the pauses required during the garbage collection for this garbage collector type.
    
    Returns:
    a List of the PauseDetails for each of the pauses required during the garbage collection for this garbage collector type.
  - getCompilersEnabled
```
public boolean getCompilersEnabled()
```
    Return whether the JVM’s runtime compiler (JIT) is enabled to compile Java methods to native code. Conditions inside the JVM can limit the ability of the runtime compiler to continue running. Most frequently, the issue is related to the lack of resource availability. For example, a code cache sized too small for the application’s demands will cause the compilers to be disabled.
    
    Returns:
    whether the JVM’s runtime compiler (JIT) is enabled to compile Java methods to native code.
  - getEndTime
```
public double getEndTime()
```
    Returns end time of the garbage collection for this type of collector in units of elapsed seconds since the start of the JVM.
    
    Returns:
    double value representing the end time of this garbage collection in units of elapsed seconds since the start of the JVM.
  - getFragmentedSpaceInGeneration
```
public long getFragmentedSpaceInGeneration()
```
    Returns the approximate difference (in units of bytes) between the size of the generations collected by this garbage collector getGarbageCollectionType() and the bytes of live objects returned by getLiveInGeneration() for this garbage collector. The returned value represents the memory that has been allocated for objects (the size of the pool) but is not available for use to allocate objects. Frequently, the fragmented space is reclaimed by garbage collectors that are able to compact the objects in the collected generations during a garbage collection.
    
    Returns:
    approximate difference (in units of bytes) between the size of the generations collected by this garbage collector and the bytes of live objects in the same generations.
  - getGarbageCollected
```
public long getGarbageCollected()
```
    Returns the aggregate size of all objects collected by this garbage collector during this garbage collection in units of bytes.
    
    Returns:
    the aggregate size of all objects collected by this garbage collector during this garbage collection in units of bytes.
  - getGarbageCollectionCause
```
public java.lang.String getGarbageCollectionCause()
```
    Returns the reason that the garbage collector was started for this garbage collection. The most common reason for starting a garbage collection is when the JVM detects that all of the available Java heap space has been occupied or the JVM estimates that all of the space will be occupied soon. Some JVMs may use the "Max" string as the string to identify this cause for starting a garbage collection. Another reason might be allocation failure, using the "Alo" string.
    
    Returns:
    String reason for starting the garbage collector.
  - getGarbageCollectionMinorMajorTotalCount
```
public long getGarbageCollectionMinorMajorTotalCount()
```
    A numeric value assigned at the start of this garbage collection: incremented by one prior to assignment for a minor collection (New Generation only); incremented by one prior to assignment for a major collection and used as the count assigned to the New Generation collection before being incremented again and assigned to the Old Generation collection that completes the major (NTO/Old) collection.
    
    The numeric value is based on a process-global counter that is incremented differently depending on the type of collection (minor or major):
    
    Minor, New Generation collection only: the collector increments the value of the process-global counter by one and uses that value as the count for the newly started collection.
    
    Major, NTO/Old (full) type collection: the New Generation collector increments the value of the process-global counter by one and uses that value as the count for the NTO (New Generation) collection. The counter is immediately incremented again and used as the count for the paired Old Generation collection.
    
    When doing a major Java heap collection, the MinorMajorTotalCount provides a label to associate the New Generation collection with the subsequent Old Generation collection.
    
    The following examples show how to use the MinorMajorTotalCount values to associate a major collection's NTO New Generation collection with its paired Old Generation collection.
    Example of a major garbage collection that completes and the MinorMajorTotalCount values (see getId() for an explanation of Id): Type Cause Id MinorMajorTotalCount New Max 782 817 incremented by one to 817 before use -- start of major collection NTO Max 783 818 incremented by one to 818 before use value incremented to 819 for use with the paired Old Old Max 36 819 Old uses the value incremented after its paired NTO -- end of major collection New Max 784 820 incremented by one from 819 to 820 Example of out of order increasing MinorMajorTotalCount values that can occur during a major collection when a second, minor (New Generation) collection completes before the completion of the major collection’s Old Generation collection. Type Cause Id MinorMajorTotalCount NTO Max 785 821 incremented by one to 821 before use value incremented to 822 for use with the paired Old New Max 786 823 New collection with Id=786 and MinorMajorTotalCount=823 starts and completes before Old completes Old Max 37 822 ** Old uses the value incremented after its paired NTO New Max 787 824 incremented by one to 824 (from 823) In the second example, the end time for the Old Generation collection (822), when its GCInfo object is available, is after the end time of a New Generation collection (823) that started and completed before the Old Generation collection completed.
    Returns:
    numeric value that identifies the start of this garbage collection relative to the start of other garbage collections in the sequence of garbage collections started in this process.
  - getGarbageCollectionType
```
public java.lang.String getGarbageCollectionType()
```
    Returns the type of garbage collection for this garbage collection. This will usually be New Generation (New), New and Old Generations (NTO), or Old Generation (Old). The Old type represents the Old Generation collection tied to the New Generation Collection for an NTO collection.
    
    Returns:
    String representing the type of garbage collection.
  - getGarbageCollectorThreadCount
```
public long getGarbageCollectorThreadCount()
```
    Returns the number of garbage collection threads in the pool of garbage collection threads for the garbage collector of this type.
    
    Returns:
    the number of garbage collection threads in the pool of garbage collection threads for the collector of this type.
  - getGarbageFound
```
public long getGarbageFound()
```
    Returns the aggregate size of all unreachable objects discovered by this garbage collector during this garbage collection in units of bytes.
    
    Returns:
    the aggregate size of all unreachable objects discovered by this garbage collector during this garbage collection in units of bytes.
  - getHasContingencyMemoryBeenUsedSinceEndOfPreviousCollection
```
public boolean getHasContingencyMemoryBeenUsedSinceEndOfPreviousCollection()
```
    Returns whether the JVM required and was able to use Contingency memory in the interval between the end of the previous collection and the end of this collection for the garbage collector of this type.
    
    Returns:
    whether Contingency memory has been in use in the interval between the end of the previous collection and the end of this collection for the collector of this type.
  - getHasPausePreventionMemoryBeenUsedSinceEndOfPreviousCollection
```
public boolean getHasPausePreventionMemoryBeenUsedSinceEndOfPreviousCollection()
```
    Returns whether the JVM required and was able to use Pause Prevention memory in the interval between the end of the previous collection and the end of this collection for the garbage collector of this type.
    
    Returns:
    whether Pause Prevention memory was in use in the interval between the end of the previous collection and the end of this collection for the collector of this type.
  - getHasRequestForPausePreventionMemoryFailedSinceEndOfPreviousCollection
```
public boolean getHasRequestForPausePreventionMemoryFailedSinceEndOfPreviousCollection()
```
    Returns whether the JVM’s request for additional Pause Prevention memory failed in the interval between the end of the previous collection and the end of this collection for the garbage collector of this type.
    
    Returns:
    whether there was insufficient Pause Prevention memory available to satisfy the request by the JVM.
  - getId
```
public long getId()
```
    Returns a monotonically increasing number representing the sequence number of this garbage collection performed by this garbage collector.
    
    Returns:
    a number identifying this garbage collection.
  - getLargeSpacePages
```
public long getLargeSpacePages()
```
    Number of pages in the large space, one of three spaces.
    
    Returns:
    number of pages in the large space.
  - getLiveInGeneration
```
public long getLiveInGeneration()
```
    Returns the approximate occupancy by live objects (in units of bytes) of the generations collected by this type of garbage collector (returned by getGarbageCollectionType() at the end of this garbage collection.
    
    Returns:
    approximate occupancy by live objects in units of bytes of the generations collected by this type of garbage collector.
  - getMaximumApplicationThreadDelay
```
public double getMaximumApplicationThreadDelay()
```
    Returns the maximum pause time in seconds for all of the application threads that were required to pause waiting for object allocation in the interval between the end of the previous collection and the end of this collection for this garbage collector. The application threads should never pause waiting for object allocation and the maximum returned is expected to always be zero for an application running correctly.
    
    Returns:
    the maximum pause time in seconds for all of the application threads that were required to pause waiting for object allocation in the interval between the end of the previous collection and the end of this collection for this collector.
  - getMaximumMemoryAvailableForJVMsJavaHeap
```
public long getMaximumMemoryAvailableForJVMsJavaHeap()
```
    The total memory available for the JVM process to use for its Java heap including the Initial Reserved memory and any additional memory available from the Java Heap’s parent pool that is available for use by the current process.
    
    Returns:
    the total amount of memory in bytes available for the JVM process to use for its Java Heap.
  - getMemoryUsageAtEndOfGC
```
public java.util.Map<java.lang.String,MemoryUsage> getMemoryUsageAtEndOfGC()
```
    Returns a Map with the MemoryUsage for each of the memory pools at the end of the garbage collection for this garbage collector type.
    
    Returns:
    a Map with the MemoryUsage for each of the memory pools at the end of the garbage collection for this garbage collector type.
  - getMemoryUsageAtStartOfGC
```
public java.util.Map<java.lang.String,MemoryUsage> getMemoryUsageAtStartOfGC()
```
    Returns a Map with the MemoryUsage for each of the memory pools at the start of the garbage collection for this garbage collector type.
    
    Returns:
    a Map with the MemoryUsage for each of the memory pools at the start of the garbage collection for this garbage collector type.
  - getMidSpacePages
```
public long getMidSpacePages()
```
    Number of pages in the mid space, one of three spaces.
    
    Returns:
    number of pages in the mid space.
  - getNoRelocatePages
```
public long getNoRelocatePages()
```
    Number of pages not relocated during this garbage collection.
    
    Returns:
    number of pages not relocated during this garbage collection.
  - getNumberOfApplicationThreadsDelayed
```
public long getNumberOfApplicationThreadsDelayed()
```
    Returns the number of times application threads were required to pause waiting for object allocation in the interval between the end of the previous collection and the end of this collection for this type of garbage collector. The application threads should never pause waiting for object allocation.
    
    Returns:
    number of application threads that were required to pause waiting for object allocation in the interval between the end of the previous collection and the end of this collection for this collector.
  - getPeakJavaHeapUsedSinceEndOfPreviousCollection
```
public long getPeakJavaHeapUsedSinceEndOfPreviousCollection()
```
    For this type of collector, the peak Java heap use between the end of the previous collection and the end of this collection.
    
    Returns:
    the peak usage of the Java heap in bytes for this collector over the interval between the end of the previous collection and the end of this collection.
  - getPeakPausePreventionMemoryUsedSinceEndOfPreviousCollection
```
public long getPeakPausePreventionMemoryUsedSinceEndOfPreviousCollection()
```
    Returns the peak Pause Prevention memory use between the end of the previous collection and the end of this collection for the garbage collector of this type.
    
    Returns:
    the peak usage of Pause Prevention memory in bytes over the interval between the end of the previous collection and the end of this collection for this type of collector.
  - getPercentageOfTimeCollectorIsRunning
```
public double getPercentageOfTimeCollectorIsRunning()
```
    For the garbage collector with the type returned by getGarbageCollectionType(), the percentage of time in seconds that this garbage collector has been running over the time interval between the end of the last previous collection of this type and the end of this collection. The percentage of time is calculated by the formula:
    ( getCollectionDuration() / ( getTimeFromEndOfPreviousToStart() + getCollectionDuration() ) ) * 100
    
    Returns:
    double value representing percentage of time the collector of this type has been running between the end of the last previous collection of this type and the end this garbage collection.
  - getPermAllocationRateBetweenEndOfPreviousAndStart
```
public double getPermAllocationRateBetweenEndOfPreviousAndStart()
```
    Returns the object allocation rate into the Permanent Generation in units of megabytes per second during the time interval between the end of the last previous collection and start of this collection for this collector type.
    
    Returns:
    the object allocation rate into the Permanent Generation in units of megabytes per second during the time interval between the end of the last previous collection and start of this collection for this collector type.
  - getPermAllocationRateDuringCollection
```
public double getPermAllocationRateDuringCollection()
```
    Returns the object allocation rate into the Permanent Generation in units of megabytes per second during the time interval between the beginning and end of this garbage collection for this type of garbage collector.
    
    Returns:
    the object allocation rate into the Permanent Generation in units of megabytes per second during the time interval between the beginning and end of this collection.
  - getPromotedPages
```
public long getPromotedPages()
```
    Number of pages promoted from the New Generation to the Old Generation during this garbage collection.
    
    Returns:
    number of pages promoted from the New Generation to the Old Generation.
  - getRelocatedPages
```
public long getRelocatedPages()
```
    Number of pages relocated during this garbage collection.
    
    Returns:
    number of pages relocated during this garbage collection.
  - getRelocSpikePages
```
public long getRelocSpikePages()
```
    Number of pages relocated that required use of a normally reserved memory area during this garbage collection.
    
    Returns:
    number of pages relocated that required use of a normally reserved memory area during this garbage collection.
  - getSidebandMemoryUse
```
public long getSidebandMemoryUse()
```
    Amount of additional memory used in bytes by the garbage collector during its marking phase. Usually, use of this memory only occurs when the allocation rate is high.
    
    Returns:
    amount of additional memory used in bytes by the garbage collector during marking.
  - getSmallSpacePages
```
public long getSmallSpacePages()
```
    Number of pages in the small space, one of three spaces.
    
    Returns:
    number of pages in the small space.
  - getStartTime
```
public double getStartTime()
```
    Returns start time of this garbage collection in units of elapsed seconds since the start of the JVM.
    
    Returns:
    double value representing the start time of this garbage collection in units of elapsed seconds since the start of the JVM.
  - getTimeFromEndOfPreviousToStart
```
public double getTimeFromEndOfPreviousToStart()
```
    For the garbage collector with the type returned by getGarbageCollectionType(), the amount of time in seconds from the end of the last previous garbage collection for this type of collector to the start of this garbage collection in units of elapsed seconds since the start of the JVM. The time interval represents the amount of time that this collector is not running.
    
    Returns:
    double value representing the amount of time in seconds from the end of the last previous garbage collection for this type of collector to the start of this garbage collection in units of elapsed seconds since the start of the JVM.
  - getTotalApplicationThreadCount
```
public long getTotalApplicationThreadCount()
```
    Returns the number of application threads in the running process. The number of application threads is determined at the end of the garbage collection.
    
    Returns:
    the number of application threads in the running process.
  - getUnreturnedPausePreventionMemory
```
public long getUnreturnedPausePreventionMemory()
```
    Answers the question whether the JVM’s memory needs are sufficiently high to require continued use of some of the Pause Prevention memory used in the interval between the end of the previous collection and the end of this collection for this collector. If the returned value is above zero then Pause Prevention memory is in use after the completion of the current collection for this collector.
    
    Returns:
    the amount of Pause Prevention memory use in bytes that is still in use after the end of this collection.
  - isAbleToUseContingencyMemory
```
public boolean isAbleToUseContingencyMemory()
```
    Indication of the state of the JVM related to the use of additional memory available from the Java Heap’s parent pool, referred to as Contingency memory. The returned value summarizes the conditions of two states:
    1. Whether there is Contingency memory available for the JVM to use.
    
    2. Whether the JVM is configured or in a state to use the additional memory.
    
    Returns:
    whether the JVM is currently able to use Contingency memory to expand the size of the Java Heap.
  - isAbleToUsePausePreventionMemory
```
public boolean isAbleToUsePausePreventionMemory()
```
    Indicates the state of the JVM related to the use of Pause Prevention memory available from the Java Heap’s parent pool. The returned value summarizes the conditions of two states:
    1. Whether there is Pause Prevention memory available for the JVM to use.
    
    2. Whether the JVM is configured or in a state to use the additional memory.
    
    Returns:
    whether the JVM is currently able to use Pause Prevention memory to expand the size of the Java Heap.
  - isValidData
```
public boolean isValidData()
```
    Returns whether the data returned GCDetails has passed all validity tests.
    
    Returns:
    true if the data in this GCDetails is valid; otherwise, return false.
  - toString
```
public java.lang.String toString()
```
    Convert this GCDetails object to a String representation.
    
    Overrides:
    
    toString in class java.lang.Object
    
    Returns:
    String representation of this GCDetails object.

Class GCDetails

Collection identifier and cause information

Zing Java heap memory used by the process

Generation metrics

Collection’s time metrics

Process’s pause prevention memory use

Process’s contingency memory use

Allocation rates

Garbage Collector threads

Application threads and whether any have been delayed while allocating

Page information

Compilers enabled

Pause times for each of the pauses required during this collection

Maximum pause times for each of the pauses required during the collection

Memory usage for each memoory pool at start of this garbage collection

Memory usage for each memoory pool at end of this garbage collection

Method Summary

Methods inherited from class java.lang.Object

Method Detail

getAllocationRateBetweenEndOfPreviousAndStart

getAllocationRateDuringCollection

getAverageApplicationThreadDelay

getCollectionDuration

getCollectorRequiredMaxPauseDetails

getCollectorRequiredPauseDetails

getCompilersEnabled

getEndTime

getFragmentedSpaceInGeneration

getGarbageCollected

getGarbageCollectionCause

getGarbageCollectionMinorMajorTotalCount

getGarbageCollectionType

getGarbageCollectorThreadCount

getGarbageFound

getHasContingencyMemoryBeenUsedSinceEndOfPreviousCollection

getHasPausePreventionMemoryBeenUsedSinceEndOfPreviousCollection

getHasRequestForPausePreventionMemoryFailedSinceEndOfPreviousCollection

getId

getLargeSpacePages

getLiveInGeneration

getMaximumApplicationThreadDelay

getMaximumMemoryAvailableForJVMsJavaHeap

getMemoryUsageAtEndOfGC

getMemoryUsageAtStartOfGC

getMidSpacePages

getNoRelocatePages

getNumberOfApplicationThreadsDelayed

getPeakJavaHeapUsedSinceEndOfPreviousCollection

getPeakPausePreventionMemoryUsedSinceEndOfPreviousCollection

getPercentageOfTimeCollectorIsRunning

getPermAllocationRateBetweenEndOfPreviousAndStart

getPermAllocationRateDuringCollection

getPromotedPages

getRelocatedPages

getRelocSpikePages

getSidebandMemoryUse

getSmallSpacePages

getStartTime

getTimeFromEndOfPreviousToStart

getTotalApplicationThreadCount

getUnreturnedPausePreventionMemory

isAbleToUseContingencyMemory

isAbleToUsePausePreventionMemory

isValidData

toString