$ strings client/jvm.dll | grep XX  # Librica Java 15

-XX:StartFlightRecording
-XX:FlightRecorderOptions
-XX:StartFlightRecording=dumponexit=false
-Xlog:%s=%s
-XX:+AggressiveHeap (You need at least 256mb of memory to use this)
-XX:MaxHeapSize=
-XX:ReservedCodeCacheSize=
-XX:+NeverTenure
-XX:+AlwaysTenure
-XX:MaxTenuringThreshold=
-XX:+DisplayVMOutputToStderr
-XX:+DisplayVMOutputToStdout
-XX:+ErrorFileToStderr
-XX:+ErrorFileToStdout
-XX:+ExtendedDTraceProbes
-XX:+ProfileInterpreter not supported in this VM
-XX:+TieredCompilation not supported in this VM
-XX:+ShowRegistersOnAssert not supported in this VM
-XX:ArchiveClassesAtExit cannot be used with -Xshare:dump
-XX:SharedArchiveFile (Cannot have more than 1 archive file specified during CDS dumping)
-XX:VMOptionsFile=
-XX:Flags=
-XX:+PrintVMOptions
-XX:-PrintVMOptions
-XX:+IgnoreUnrecognizedVMOptions
-XX:-IgnoreUnrecognizedVMOptions
-XX:+PrintFlagsInitial
-XX:NativeMemoryTracking=[off|summary|detail]
-XX:+EnableDynamicAgentLoading (Use to launch target VM.)
-XX:ReservedCodeCacheSize=
-XX:CompileCommand=exclude,java/*.* -XX:CompileCommand=log,java*.*
-XX:CompileCommandFile=<file> or be added to the file '.hotspot_compiler'
   Usage: '-XX:CompileCommand=command,"package/Class.method()"'
   Use:   '-XX:CompileCommand=help' for more information.
-XX:+LogTouchedMethods
-XX:+AlwaysPreTouch (To avoid memory commit hiccups)

-XX:+UnlockDiagnosticVMOptions
-XX:+UnlockExperimentalVMOptions
-XX:LogFile=

-XX:+UseG1GC (can not be combined with -XX:ParallelGCThreads=0)
-XX:+UseZGC (can not be combined with -XX:ParallelGCThreads=0 or -XX:ConcGCThreads=0)
-XX:+UseShenandoahGC

-XX:NewSize and -XX:MaxNewSize override -XX:NewRatio
The Parallel GC can not be combined with -XX:ParallelGCThreads=0

# From <https://wiki.openjdk.java.net/display/shenandoah/Main>:
-XX:ShenandoahImmediateThreshold=100
-XX:+ShenandoahEvacReserveOverflow
-XX:ShenandoahUnloadClassesFrequency=1
-XX:+ExplicitGCInvokesConcurrent
-XX:+ShenandoahImplicitGCInvokesConcurrent
-XX:+ShenandoahUncommit
-XX:+ShenandoahAlwaysClearSoftRefs
-XX:ShenandoahAllocationThreshold=10
-XX:ShenandoahUncommitDelay=1000
-XX:ShenandoahGuaranteedGCInterval=30000
-XX:ShenandoahGarbageThreshold=10
-XX:+ShenandoahLoadRefBarrier
-XX:-ShenandoahSATBBarrier
-XX:+ShenandoahStoreValEnqueueBarrier
-XX:+ShenandoahCASBarrier
-XX:+ShenandoahCloneBarrier
Unknown -XX:ShenandoahGCHeuristics option
-XX:-ShenandoahPacing
-XX:ShenandoahEvacReserve=0
-XX:-ShenandoahLoadRefBarrier
-XX:-ShenandoahSATBBarrier
-XX:-ShenandoahStoreValEnqueueBarrier
-XX:-ShenandoahCASBarrier
-XX:-ShenandoahCloneBarrier
-XX:-ShenandoahStoreValEnqueueBarrier
-XX:+ShenandoahSATBBarrier
-XX:+UseLargePages
-XX:+UseNUMA
-XX:-UseBiasedLocking
XX:+DisableExplicitGC
-XX:+ExplicitGCInvokesConcurrent

-XX:+RestoreMXCSROnJNICall
-XX:ReservedCodeCacheSize=
-XX:HeapBaseMinAddress
-XX:OnError=
-XX:OnOutOfMemoryError=
-XX:ZMarkStackSpaceLimit=<size>