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Collection of HotSpot JVM flags for various purposes (mainly performance related)
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Collection of JVM flags.md

Minimum JVM Flags

  • https://gist.github.com/sushanthmangalore/69871cbc87c97cbca67a130469fdee90
  • Guide to the Most Important JVM Parameters
  • Minimum flags to record GC logs (plus enabling safepoint stats)
    • Java 8
      -Xloggc:/path/to/gc.log    # <Location to write your GC log to>
  -XX:LogFile=<Location to write your Safepoint log to>
  -XX:+UseGCLogFileRotation 
  -XX:NumberOfGCLogFiles=< number of log files > 
  -XX:GCLogFileSize=< file size >[ unit ]
  -XX:+UnlockDiagnosticVMOptions
  -XX:+PrintGCDetails
  -XX:+PrintTenuringDistribution
  -XX:+PrintGCCause
  -XX:+PrintGCApplicationStoppedTime
  -XX:+PrintGCDateStamps
  -XX:+PrintGCTimeStamps   
  -XX:+PrintSafepointStatistics
  -XX:+LogVMOutput
  -XX:+HeapDumpOnOutOfMemoryError
  -XX:HeapDumpPath=./java_pid<pid>.hprof
  -XX:+CMSClassUnloadingEnabled       ### Pre-Java-8
  -XX:+UseGCOverheadLimit
  # Some more, check before using
  -XX:OnOutOfMemoryError="< cmd args >;< cmd args >"
    • Java 11 and above
      -Xlog:gc=[warning|debug|error]:file=/path/to/gc.log:time,uptime,level,tags:filecoint=[n],filesize=[n]m
  -XX:+UnlockDiagnosticVMOptions
  -XX:LogFile=<Location to write your Safepoint log to>
  -XX:+LogVMOutput
  -XX:+HeapDumpOnOutOfMemoryError
  -XX:HeapDumpPath=./java_pid-%p.hprof
  -XX:+UseGCOverheadLimit
  -XX:FlightRecorderOptions=stackdepth=[nn]

See java command, arguments/parameters for Java 9 to find equivalents for Java 9 flags and java command, arguments/parameters for Java 11 for Java 11 flags.

Performance related JVM Flags

General/Misc

JIT

Java

Scala

Webserver

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