"-XX:+PrintFlagsFinal" - Print JVM Options

This section describes the '-XX:+PrintFlagsFinal' JVM option, which prints all options and their values used by the JVM.

If want to know what are default options used by the JVM, you can use the "-XX:+PrintFlagsFinal" option to print them out:

C:\>\progra~1\java\jdk1.8.0\bin\java 
   -XX:+PrintFlagsFinal GarbageCollection

[Global flags]
    uintx AdaptiveSizeDecrementScaleFactor          = 4  
    uintx AdaptiveSizeMajorGCDecayTimeScale         = 10 
    uintx AdaptiveSizePausePolicy                   = 0  
    uintx AdaptiveSizePolicyCollectionCostMargin    = 50 
    uintx AdaptiveSizePolicyInitializingSteps       = 20 
      ...
     bool AlwaysTenure                              = false      
    uintx AutoGCSelectPauseMillis                   = 5000       
     bool CMSAbortSemantics                         = false      
    uintx CMSAbortablePrecleanMinWorkPerIteration   = 100        
     intx CMSAbortablePrecleanWaitMillis            = 100        
    uintx CMSBitMapYieldQuantum                     = 10485760   
   double G1ConcMarkStepDurationMillis              = 10.000000  
    uintx G1ConcRSHotCardLimit                      = 4          
    uintx G1ConcRSLogCacheSize                      = 10         
    uintx GCHeapFreeLimit                           = 2          
    uintx GCLockerEdenExpansionPercent              = 5          
     bool GCLockerInvokesConcurrent                 = false      
    uintx GCLogFileSize                             = 8192       
    uintx GCPauseIntervalMillis                     = 0          
    uintx GCTaskTimeStampEntries                    = 200        
    uintx GCTimeLimit                               = 98         
    uintx GCTimeRatio                               = 99         
    uintx InitialHeapSize                          := 16777216   
    uintx InitialSurvivorRatio                      = 8          
    uintx InitialTenuringThreshold                  = 7          
    uintx MaxNewSize                               := 89456640   
    uintx MinHeapFreeRatio                          = 40         
    uintx MinSurvivorRatio                          = 3          
    uintx NewRatio                                  = 2          
    uintx NewSize                                  := 5570560    
    uintx NewSizeThreadIncrease                     = 4096       
     intx ParGCArrayScanChunk                       = 50         
    uintx ParGCDesiredObjsFromOverflowList          = 20         
     bool ParGCTrimOverflow                         = true       
     bool ParGCUseLocalOverflow                     = false      
    uintx ParallelGCBufferWastePct                  = 10         
    uintx ParallelGCThreads                         = 0          
     bool ParallelGCVerbose                         = false      
    uintx ParallelOldDeadWoodLimiterMean            = 50         
    uintx ParallelOldDeadWoodLimiterStdDev          = 80         
     bool ParallelRefProcBalancingEnabled           = true       
     bool ParallelRefProcEnabled                    = false      
     bool PrintCMSInitiationStatistics              = false      
     intx PrintCMSStatistics                        = 0          
     bool PrintGC                                   = false      
     bool PrintGCApplicationConcurrentTime          = false      
     bool PrintGCApplicationStoppedTime             = false      
     bool PrintGCCause                              = true       
     bool PrintGCDateStamps                         = false      
     bool PrintGCDetails                            = false      
     bool PrintGCID                                 = false      
     bool PrintGCTaskTimeStamps                     = false      
     bool PrintGCTimeStamps                         = false      
     bool PrintHeapAtGC                             = false      
    uintx SurvivorPadding                           = 3          
    uintx SurvivorRatio                             = 8          
     bool UseCMSBestFit                             = true       
     bool UseCMSCollectionPassing                   = true       
     bool UseCMSCompactAtFullCollection             = true       
     bool UseCMSInitiatingOccupancyOnly             = false      
     bool UseConcMarkSweepGC                        = false      
     bool UseG1GC                                   = false      
     bool UseGCLogFileRotation                      = false      
     bool UseGCOverheadLimit                        = true       
     bool UseGCTaskAffinity                         = false      
     bool UsePSAdaptiveSurvivorSizePolicy           = true       
     bool UseParNewGC                               = false      
     bool UseParallelGC                             = false      
     bool UseParallelOldGC                          = false      
     bool UseSerialGC                               = false      
    uintx YoungGenerationSizeIncrement              = 20         
    uintx YoungGenerationSizeSupplement             = 80         
    uintx YoungGenerationSizeSupplementDecay        = 8          
    uintx YoungPLABSize                             = 4096       
      ...

Last update: 2018.

Table of Contents

 About This Book

 Heap Memory Area and Size Control

JVM Garbage Collection Logging

 Garbage Collection Demo Program

 Garbage Collection Logging Options

 "-XX:+PrintGC" - GC Logging Option for Short Messages

 "-XX:+PrintGCDetails" - Option for Detailed GC Messages

 "-XX:+PrintGCDateStamps" - Calendar Timestamp on GC Messages

 "-XX:+PrintGCApplicationStoppedTime" - Application Pause Durations

 "-XX:+PrintGCApplicationConcurrentTime" - Application Running Durations

 "-XX:+PrintHeapAtGC" - Print Heap Summary per GC

 "-XX:+PrintTenuringDistribution" - Tunuring Distribution

 "-XX:+PrintReferenceGC" - Reference Counts per GC

"-XX:+PrintFlagsFinal" - Print JVM Options

 Introduction of Garbage Collectors

 Serial Collector - "+XX:+UseSerialGC"

 Parallel Collector - "+XX:+UseParallelGC"

 Concurrent Mark-Sweep (CMS) Collector - "+XX:+UseConcMarkSweepGC"

 Garbage First (G1) Collector - "+XX:+UseG1GC"

 Object References and Garbage Collection

 Garbage Collection Performance Test Program

 Performance Tests on Serial Collector

 Performance Tests on Parallel collector

 Performance Tests on Concurrent collector

 Performance Tests on G1 collector

 Garbage Collection Performance Test Summary

 Outdated Tutorials

 References

 Full Version in PDF/EPUB