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<a href="../djdknativersa/" title="-Djdk.nativeRSA" class="md-nav__link">
-Djdk.nativeRSA
</a>
</li>
</ul>
</nav>
</li>
<li class="md-nav__item md-nav__item--nested">
<input class="md-toggle md-nav__toggle" data-md-toggle="nav-11-5" type="checkbox" id="nav-11-5">
<label class="md-nav__link" for="nav-11-5">
JVM -X options
</label>
<nav class="md-nav" data-md-component="collapsible" data-md-level="2">
<label class="md-nav__title" for="nav-11-5">
JVM -X options
</label>
<ul class="md-nav__list" data-md-scrollfix>
<li class="md-nav__item">
<a href="../x_jvm_commands/" title="Using -X options" class="md-nav__link">
Using -X options
</a>
</li>
<li class="md-nav__item">
<a href="../x/" title="-X" class="md-nav__link">
-X
</a>
</li>
<li class="md-nav__item">
<a href="../xaggressive/" title="-Xaggressive" class="md-nav__link">
-Xaggressive
</a>
</li>
<li class="md-nav__item">
<a href="../xalwaysclassgc/" title="-Xalwaysclassgc" class="md-nav__link">
-Xalwaysclassgc
</a>
</li>
<li class="md-nav__item">
<a href="../xaot/" title="-Xaot" class="md-nav__link">
-Xaot
</a>
</li>
<li class="md-nav__item">
<a href="../xargencoding/" title="-Xargencoding" class="md-nav__link">
-Xargencoding
</a>
</li>
<li class="md-nav__item">
<a href="../xbootclasspath/" title="-Xbootclasspath" class="md-nav__link">
-Xbootclasspath
</a>
</li>
<li class="md-nav__item">
<a href="../xceehdlr/" title="-XCEEHDLR" class="md-nav__link">
-XCEEHDLR
</a>
</li>
<li class="md-nav__item">
<a href="../xcheck/" title="-Xcheck" class="md-nav__link">
-Xcheck
</a>
</li>
<li class="md-nav__item">
<a href="../xclassgc/" title="-Xclassgc" class="md-nav__link">
-Xclassgc
</a>
</li>
<li class="md-nav__item">
<a href="../xcodecache/" title="-Xcodecache" class="md-nav__link">
-Xcodecache
</a>
</li>
<li class="md-nav__item">
<a href="../xcodecachetotal/" title="-Xcodecachetotal" class="md-nav__link">
-Xcodecachetotal
</a>
</li>
<li class="md-nav__item">
<a href="../xcomp/" title="-Xcomp" class="md-nav__link">
-Xcomp
</a>
</li>
<li class="md-nav__item">
<a href="../xcompactexplicitgc/" title="-Xcompactexplicitgc" class="md-nav__link">
-Xcompactexplicitgc
</a>
</li>
<li class="md-nav__item">
<a href="../xcompactgc/" title="-Xcompactgc" class="md-nav__link">
-Xcompactgc
</a>
</li>
<li class="md-nav__item">
<a href="../xcompilationthreads/" title="-XcompilationThreads" class="md-nav__link">
-XcompilationThreads
</a>
</li>
<li class="md-nav__item">
<a href="../xcompressedrefs/" title="-Xcompressedrefs" class="md-nav__link">
-Xcompressedrefs
</a>
</li>
<li class="md-nav__item">
<a href="../xconcurrentbackground/" title="-Xconcurrentbackground" class="md-nav__link">
-Xconcurrentbackground
</a>
</li>
<li class="md-nav__item">
<a href="../xconcurrentlevel/" title="-Xconcurrentlevel" class="md-nav__link">
-Xconcurrentlevel
</a>
</li>
<li class="md-nav__item">
<a href="../xconcurrentslack/" title="-Xconcurrentslack" class="md-nav__link">
-Xconcurrentslack
</a>
</li>
<li class="md-nav__item">
<a href="../xconmeter/" title="-Xconmeter" class="md-nav__link">
-Xconmeter
</a>
</li>
<li class="md-nav__item">
<a href="../xenableexcessivegc/" title="-Xdisableexcessivegc" class="md-nav__link">
-Xdisableexcessivegc
</a>
</li>
<li class="md-nav__item">
<a href="../xenableexplicitgc/" title="-Xdisableexplicitgc" class="md-nav__link">
-Xdisableexplicitgc
</a>
</li>
<li class="md-nav__item">
<a href="../xdisablejavadump/" title="-Xdisablejavadump" class="md-nav__link">
-Xdisablejavadump
</a>
</li>
<li class="md-nav__item">
<a href="../xenablestringconstantgc/" title="-Xdisablestringconstantgc" class="md-nav__link">
-Xdisablestringconstantgc
</a>
</li>
<li class="md-nav__item">
<a href="../xdump/" title="-Xdump" class="md-nav__link">
-Xdump
</a>
</li>
<li class="md-nav__item">
<a href="../xenableexcessivegc/" title="-Xenableexcessivegc" class="md-nav__link">
-Xenableexcessivegc
</a>
</li>
<li class="md-nav__item">
<a href="../xenableexplicitgc/" title="-Xenableexplicitgc" class="md-nav__link">
-Xenableexplicitgc
</a>
</li>
<li class="md-nav__item">
<a href="../xenablestringconstantgc/" title="-Xenablestringconstantgc" class="md-nav__link">
-Xenablestringconstantgc
</a>
</li>
<li class="md-nav__item">
<a href="../xfastresolve/" title="-Xfastresolve" class="md-nav__link">
-Xfastresolve
</a>
</li>
<li class="md-nav__item">
<a href="../xfuture/" title="-Xfuture" class="md-nav__link">
-Xfuture
</a>
</li>
<li class="md-nav__item">
<a href="../xgc/" title="-Xgc" class="md-nav__link">
-Xgc
</a>
</li>
<li class="md-nav__item">
<a href="../xgcsplitheap/" title="-Xgc:splitheap" class="md-nav__link">
-Xgc:splitheap
</a>
</li>
<li class="md-nav__item">
<a href="../xgcpolicy/" title="-Xgcpolicy" class="md-nav__link">
-Xgcpolicy
</a>
</li>
<li class="md-nav__item">
<a href="../xgcthreads/" title="-Xgcthreads" class="md-nav__link">
-Xgcthreads
</a>
</li>
<li class="md-nav__item">
<a href="../xgcworkpackets/" title="-Xgcworkpackets" class="md-nav__link">
-Xgcworkpackets
</a>
</li>
<li class="md-nav__item">
<a href="../xifa/" title="-Xifa" class="md-nav__link">
-Xifa
</a>
</li>
<li class="md-nav__item">
<a href="../xint/" title="-Xint" class="md-nav__link">
-Xint
</a>
</li>
<li class="md-nav__item">
<a href="../xss/" title="-Xiss" class="md-nav__link">
-Xiss
</a>
</li>
<li class="md-nav__item">
<a href="../xjit/" title="-Xjit" class="md-nav__link">
-Xjit
</a>
</li>
<li class="md-nav__item">
<a href="../xjni/" title="-Xjni" class="md-nav__link">
-Xjni
</a>
</li>
<li class="md-nav__item">
<a href="../xlinenumbers/" title="-Xlinenumbers" class="md-nav__link">
-Xlinenumbers
</a>
</li>
<li class="md-nav__item">
<a href="../xloa/" title="-Xloa" class="md-nav__link">
-Xloa
</a>
</li>
<li class="md-nav__item">
<a href="../xloaminimum/" title="-Xloainitial" class="md-nav__link">
-Xloainitial
</a>
</li>
<li class="md-nav__item">
<a href="../xloaminimum/" title="-Xloamaximum" class="md-nav__link">
-Xloamaximum
</a>
</li>
<li class="md-nav__item">
<a href="../xloaminimum/" title="-Xloaminimum" class="md-nav__link">
-Xloaminimum
</a>
</li>
<li class="md-nav__item">
<a href="../xlockreservation/" title="-XlockReservation" class="md-nav__link">
-XlockReservation
</a>
</li>
<li class="md-nav__item">
<a href="../xlockword/" title="-Xlockword" class="md-nav__link">
-Xlockword
</a>
</li>
<li class="md-nav__item">
<a href="../xlog/" title="-Xlog" class="md-nav__link">
-Xlog
</a>
</li>
<li class="md-nav__item">
<a href="../xlp/" title="-Xlp" class="md-nav__link">
-Xlp
</a>
</li>
<li class="md-nav__item">
<a href="../xlpcodecache/" title="-Xlp:codecache" class="md-nav__link">
-Xlp:codecache
</a>
</li>
<li class="md-nav__item">
<a href="../xlpobjectheap/" title="-Xlp:objectheap" class="md-nav__link">
-Xlp:objectheap
</a>
</li>
<li class="md-nav__item">
<a href="../xmine/" title="-Xmaxe" class="md-nav__link">
-Xmaxe
</a>
</li>
<li class="md-nav__item">
<a href="../xminf/" title="-Xmaxf" class="md-nav__link">
-Xmaxf
</a>
</li>
<li class="md-nav__item">
<a href="../xmint/" title="-Xmaxt" class="md-nav__link">
-Xmaxt
</a>
</li>
<li class="md-nav__item">
<a href="../xmca/" title="-Xmca" class="md-nav__link">
-Xmca
</a>
</li>
<li class="md-nav__item">
<a href="../xmca/" title="-Xmco" class="md-nav__link">
-Xmco
</a>
</li>
<li class="md-nav__item">
<a href="../xmcrs/" title="-Xmcrs" class="md-nav__link">
-Xmcrs
</a>
</li>
<li class="md-nav__item">
<a href="../xmine/" title="-Xmine" class="md-nav__link">
-Xmine
</a>
</li>
<li class="md-nav__item">
<a href="../xminf/" title="-Xminf" class="md-nav__link">
-Xminf
</a>
</li>
<li class="md-nav__item">
<a href="../xmint/" title="-Xmint" class="md-nav__link">
-Xmint
</a>
</li>
<li class="md-nav__item">
<a href="../xmn/" title="-Xmn" class="md-nav__link">
-Xmn
</a>
</li>
<li class="md-nav__item">
<a href="../xmn/" title="-Xmns" class="md-nav__link">
-Xmns
</a>
</li>
<li class="md-nav__item">
<a href="../xmn/" title="-Xmnx" class="md-nav__link">
-Xmnx
</a>
</li>
<li class="md-nav__item">
<a href="../xmo/" title="-Xmo" class="md-nav__link">
-Xmo
</a>
</li>
<li class="md-nav__item">
<a href="../xmo/" title="-Xmoi" class="md-nav__link">
-Xmoi
</a>
</li>
<li class="md-nav__item">
<a href="../xmo/" title="-Xmos" class="md-nav__link">
-Xmos
</a>
</li>
<li class="md-nav__item">
<a href="../xmo/" title="-Xmox" class="md-nav__link">
-Xmox
</a>
</li>
<li class="md-nav__item">
<a href="../xmr/" title="-Xmr" class="md-nav__link">
-Xmr
</a>
</li>
<li class="md-nav__item">
<a href="../xmr/" title="-Xmrx" class="md-nav__link">
-Xmrx
</a>
</li>
<li class="md-nav__item">
<a href="../xms/" title="-Xms" class="md-nav__link">
-Xms
</a>
</li>
<li class="md-nav__item">
<a href="../xmso/" title="-Xmso" class="md-nav__link">
-Xmso
</a>
</li>
<li class="md-nav__item">
<a href="../xms/" title="-Xmx" class="md-nav__link">
-Xmx
</a>
</li>
<li class="md-nav__item">
<a href="../xaot/" title="-Xnoaot" class="md-nav__link">
-Xnoaot
</a>
</li>
<li class="md-nav__item">
<a href="../xclassgc/" title="-Xnoclassgc" class="md-nav__link">
-Xnoclassgc
</a>
</li>
<li class="md-nav__item">
<a href="../xcompactexplicitgc/" title="-Xnocompactexplicitgc" class="md-nav__link">
-Xnocompactexplicitgc
</a>
</li>
<li class="md-nav__item">
<a href="../xcompactgc/" title="-Xnocompactgc" class="md-nav__link">
-Xnocompactgc
</a>
</li>
<li class="md-nav__item">
<a href="../xcompressedrefs/" title="-Xnocompressedrefs" class="md-nav__link">
-Xnocompressedrefs
</a>
</li>
<li class="md-nav__item">
<a href="../xjit/" title="-Xnojit" class="md-nav__link">
-Xnojit
</a>
</li>
<li class="md-nav__item">
<a href="../xlinenumbers/" title="-Xnolinenumbers" class="md-nav__link">
-Xnolinenumbers
</a>
</li>
<li class="md-nav__item">
<a href="../xloa/" title="-Xnoloa" class="md-nav__link">
-Xnoloa
</a>
</li>
<li class="md-nav__item">
<a href="../xsigcatch/" title="-Xnosigcatch" class="md-nav__link">
-Xnosigcatch
</a>
</li>
<li class="md-nav__item">
<a href="../xsigchain/" title="-Xnosigchain" class="md-nav__link">
-Xnosigchain
</a>
</li>
<li class="md-nav__item">
<a href="../xnumanone/" title="-Xnuma:none" class="md-nav__link">
-Xnuma:none
</a>
</li>
<li class="md-nav__item">
<a href="../xoptionsfile/" title="-Xoptionsfile" class="md-nav__link">
-Xoptionsfile
</a>
</li>
<li class="md-nav__item">
<a href="../xquickstart/" title="-Xquickstart" class="md-nav__link">
-Xquickstart
</a>
</li>
<li class="md-nav__item">
<a href="../xrs/" title="-Xrs" class="md-nav__link">
-Xrs
</a>
</li>
<li class="md-nav__item">
<a href="../xsamplingexpirationtime/" title="-XsamplingExpirationTime" class="md-nav__link">
-XsamplingExpirationTime
</a>
</li>
<li class="md-nav__item">
<a href="../xscdmx/" title="-Xscdmx" class="md-nav__link">
-Xscdmx
</a>
</li>
<li class="md-nav__item">
<a href="../xscminaot/" title="-Xscmaxaot" class="md-nav__link">
-Xscmaxaot
</a>
</li>
<li class="md-nav__item">
<a href="../xscminjitdata/" title="-Xscmaxjitdata" class="md-nav__link">
-Xscmaxjitdata
</a>
</li>
<li class="md-nav__item">
<a href="../xscminaot/" title="-Xscminaot" class="md-nav__link">
-Xscminaot
</a>
</li>
<li class="md-nav__item">
<a href="../xscminjitdata/" title="-Xscminjitdata" class="md-nav__link">
-Xscminjitdata
</a>
</li>
<li class="md-nav__item">
<a href="../xscmx/" title="-Xscmx" class="md-nav__link">
-Xscmx
</a>
</li>
<li class="md-nav__item">
<a href="../xshareclasses/" title="-Xshareclasses" class="md-nav__link">
-Xshareclasses
</a>
</li>
<li class="md-nav__item">
<a href="../xsigcatch/" title="-Xsigcatch" class="md-nav__link">
-Xsigcatch
</a>
</li>
<li class="md-nav__item">
<a href="../xsigchain/" title="-Xsigchain" class="md-nav__link">
-Xsigchain
</a>
</li>
<li class="md-nav__item">
<a href="../xsignal/" title="-Xsignal" class="md-nav__link">
-Xsignal
</a>
</li>
<li class="md-nav__item">
<a href="../xsoftmx/" title="-Xsoftmx" class="md-nav__link">
-Xsoftmx
</a>
</li>
<li class="md-nav__item">
<a href="../xsoftrefthreshold/" title="-Xsoftrefthreshold" class="md-nav__link">
-Xsoftrefthreshold
</a>
</li>
<li class="md-nav__item">
<a href="../xss/" title="-Xss" class="md-nav__link">
-Xss
</a>
</li>
<li class="md-nav__item">
<a href="../xss/" title="-Xssi" class="md-nav__link">
-Xssi
</a>
</li>
<li class="md-nav__item">
<a href="../xtgc/" title="-Xtgc" class="md-nav__link">
-Xtgc
</a>
</li>
<li class="md-nav__item">
<a href="../xthr/" title="-Xthr" class="md-nav__link">
-Xthr
</a>
</li>
<li class="md-nav__item">
<a href="../xtlhprefetch/" title="-XtlhPrefetch" class="md-nav__link">
-XtlhPrefetch
</a>
</li>
<li class="md-nav__item">
<a href="../xtrace/" title="-Xtrace" class="md-nav__link">
-Xtrace
</a>
</li>
<li class="md-nav__item">
<a href="../xtunevirtualized/" title="-Xtune:virtualized" class="md-nav__link">
-Xtune:virtualized
</a>
</li>
<li class="md-nav__item">
<a href="../xverbosegclog/" title="-Xverbosegclog" class="md-nav__link">
-Xverbosegclog
</a>
</li>
<li class="md-nav__item">
<a href="../xverify/" title="-Xverify" class="md-nav__link">
-Xverify
</a>
</li>
<li class="md-nav__item">
<a href="../xzero/" title="-Xzero" class="md-nav__link">
-Xzero
</a>
</li>
</ul>
</nav>
</li>
<li class="md-nav__item md-nav__item--active md-nav__item--nested">
<input class="md-toggle md-nav__toggle" data-md-toggle="nav-11-6" type="checkbox" id="nav-11-6" checked>
<label class="md-nav__link" for="nav-11-6">
JVM -XX options
</label>
<nav class="md-nav" data-md-component="collapsible" data-md-level="2">
<label class="md-nav__title" for="nav-11-6">
JVM -XX options
</label>
<ul class="md-nav__list" data-md-scrollfix>
<li class="md-nav__item">
<a href="../xx_jvm_commands/" title="Using -XX options" class="md-nav__link">
Using -XX options
</a>
</li>
<li class="md-nav__item">
<a href="../xxactiveprocessorcount/" title="-XXActiveProcessorCount" class="md-nav__link">
-XXActiveProcessorCount
</a>
</li>
<li class="md-nav__item">
<a href="../xxallowvmshutdown/" title="-XXallowvmshutdown" class="md-nav__link">
-XXallowvmshutdown
</a>
</li>
<li class="md-nav__item">
<a href="../xxcodecachetotal/" title="-XX:codecachetotal" class="md-nav__link">
-XX:codecachetotal
</a>
</li>
<li class="md-nav__item">
<a href="../xxdisableexplicitgc/" title="-XX:[+|-]DisableExplicitGC" class="md-nav__link">
-XX:[+|-]DisableExplicitGC
</a>
</li>
<li class="md-nav__item">
<a href="../xxdisclaimjitscratch/" title="-XX:[+|-]DisclaimJitScratch" class="md-nav__link">
-XX:[+|-]DisclaimJitScratch
</a>
</li>
<li class="md-nav__item">
<a href="../xxenablecpumonitor/" title="-XX:[+|-]EnableCPUMonitor" class="md-nav__link">
-XX:[+|-]EnableCPUMonitor
</a>
</li>
<li class="md-nav__item">
<a href="../xxhandlesigxfsz/" title="-XX:[+|-]handleSIGXFSZ" class="md-nav__link">
-XX:[+|-]handleSIGXFSZ
</a>
</li>
<li class="md-nav__item">
<a href="../xxheapdumponoutofmemory/" title="-XX:[+|-]HeapDumpOnOutOfMemory" class="md-nav__link">
-XX:[+|-]HeapDumpOnOutOfMemory
</a>
</li>
<li class="md-nav__item">
<a href="../xxheapdumppath/" title="-XX:HeapDumpPath" class="md-nav__link">
-XX:HeapDumpPath
</a>
</li>
<li class="md-nav__item">
<a href="../xxheapmanagementmxbeancompatibility/" title="-XX:[+|-]HeapManagementMXBeanCompatibility" class="md-nav__link">
-XX:[+|-]HeapManagementMXBeanCompatibility
</a>
</li>
<li class="md-nav__item">
<a href="../xxidletuningcompactonidle/" title="-XX:[+|-]IdleTuningCompactOnIdle" class="md-nav__link">
-XX:[+|-]IdleTuningCompactOnIdle
</a>
</li>
<li class="md-nav__item">
<a href="../xxidletuninggconidle/" title="-XX:[+|-]IdleTuningGcOnIdle" class="md-nav__link">
-XX:[+|-]IdleTuningGcOnIdle
</a>
</li>
<li class="md-nav__item">
<a href="../xxidletuningminfreeheaponidle/" title="-XX:IdleTuningMinFreeHeapOnIdle" class="md-nav__link">
-XX:IdleTuningMinFreeHeapOnIdle
</a>
</li>
<li class="md-nav__item">
<a href="../xxidletuningminidlewaittime/" title="-XX:IdleTuningMinIdleWaitTime" class="md-nav__link">
-XX:IdleTuningMinIdleWaitTime
</a>
</li>
<li class="md-nav__item">
<a href="../xxignoreunrecognizedvmoptions/" title="-XX:[+|-]IgnoreUnrecognizedVMOptions" class="md-nav__link">
-XX:[+|-]IgnoreUnrecognizedVMOptions
</a>
</li>
<li class="md-nav__item">
<a href="../xxignoreunrecognizedxxcolonoptions/" title="-XX:[+|-]IgnoreUnrecognizedXXColonOptions" class="md-nav__link">
-XX:[+|-]IgnoreUnrecognizedXXColonOptions
</a>
</li>
<li class="md-nav__item">
<a href="../xxinitialrampercentage/" title="-XX:InitialRAMPercentage" class="md-nav__link">
-XX:InitialRAMPercentage
</a>
</li>
<li class="md-nav__item">
<a href="../xxinitialheapsize/" title="-XX:InitialHeapSize" class="md-nav__link">
-XX:InitialHeapSize
</a>
</li>
<li class="md-nav__item">
<a href="../xxinterleavememory/" title="-XX:[+|-]InterleaveMemory" class="md-nav__link">
-XX:[+|-]InterleaveMemory
</a>
</li>
<li class="md-nav__item">
<a href="../xxjitinlinewatches/" title="-XX:[+|-]JITInlineWatches" class="md-nav__link">
-XX:[+|-]JITInlineWatches
</a>
</li>
<li class="md-nav__item">
<a href="../xxlazysymbolresolution/" title="-XX:[+|-]LazySymbolResolution" class="md-nav__link">
-XX:[+|-]LazySymbolResolution
</a>
</li>
<li class="md-nav__item">
<a href="../xxmaxdirectmemorysize/" title="-XX:MaxDirectMemorySize" class="md-nav__link">
-XX:MaxDirectMemorySize
</a>
</li>
<li class="md-nav__item">
<a href="../xxinitialheapsize/" title="-XX:MaxHeapSize" class="md-nav__link">
-XX:MaxHeapSize
</a>
</li>
<li class="md-nav__item">
<a href="../xxinitialrampercentage/" title="-XX:MaxRAMPercentage" class="md-nav__link">
-XX:MaxRAMPercentage
</a>
</li>
<li class="md-nav__item">
<a href="../xxonoutofmemoryerror/" title="-XX:OnOutOfMemoryError" class="md-nav__link">
-XX:OnOutOfMemoryError
</a>
</li>
<li class="md-nav__item">
<a href="../xxnosuballoc32bitmem/" title="-XXnosuballoc32bitmem" class="md-nav__link">
-XXnosuballoc32bitmem
</a>
</li>
<li class="md-nav__item">
<a href="../xxpagealigndirectmemory/" title="-XX:[+|-]PageAlignDirectMemory" class="md-nav__link">
-XX:[+|-]PageAlignDirectMemory
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<h1 id="-xx91-93reducecpumonitoroverhead">-XX:[+|-]ReduceCPUMonitorOverhead</h1>
<p><strong>(AIX&reg;, Linux&reg;, macOS&reg;, and Windows&trade; only)</strong></p>
<p>This option relates to the CPU usage of thread categories that can be obtained with the <code>com.ibm.lang.management.JvmCpuMonitorMXBean</code> application programming interface. This option affects the way that the VM records the amount of CPU usage of non-Garbage Collection (GC) threads that do work on behalf of GC.</p>
<p>Most GC policies require non-GC threads to do some GC housekeeping work in proportion to the amount of memory allocation that they do. Ideally the exact amount of CPU time that the thread spends doing this housekeeping work should be accounted for in the GC thread category. However there is an overhead that is associated with maintaining the CPU usage data in the correct thread category.</p>
<p><i class="fa fa-exclamation-triangle" aria-hidden="true"></i> <strong>Restriction:</strong> This option is not supported on z/OS&reg;. If you attempt to use this option, the following message is generated:</p>
<pre><code>JVMJ9VM145E -XX:-ReduceCPUMonitorOverhead is unsupported on z/OS. Error: Could not create the Java Virtual Machine.
</code></pre>
<h2 id="syntax">Syntax</h2>
<p>-XX:[+|-]ReduceCPUMonitorOverhead</p>
<table>
<thead>
<tr>
<th>Setting</th>
<th>Effect</th>
<th align="center">Default</th>
</tr>
</thead>
<tbody>
<tr>
<td><code>-XX:+ReduceCPUMonitorOverhead</code></td>
<td>Enable</td>
<td align="center"><i class="fa fa-check" aria-hidden="true"></i><span class="sr-only">yes</span></td>
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<tr>
<td><code>-XX:-ReduceCPUMonitorOverhead</code></td>
<td>Disable</td>
<td align="center"></td>
</tr>
</tbody>
</table>
<p>When you enable this option, the VM does not maintain information on the amount of CPU usage that non-GC threads spend in doing work on behalf of GC.
If you set <code>-XX:-ReduceCPUMonitorOverhead</code>, the OpenJ9 VM monitors the amount of GC work that a non-GC thread does and accounts for it in the GC category. This information is made available in the <code>com.ibm.lang.management.JvmCpuMonitorMXBean</code>. Setting this option results in a small increase in application startup time, which varies according to platform.</p>
<h2 id="see-also">See also</h2>
<ul>
<li><a href="../xxenablecpumonitor/#xx/|-/enablecpumonitor" title="This option relates to the information about the CPU usage of thread categories that is available with the com.ibm.lang.management.JvmCpuMonitorMXBean application programming interface. CPU monitoring is enabled by default, and can be disabled by the command line option -XX:-EnableCPUMonitor. This option might not be supported in subsequent releases.">-XX:[+|-]EnableCPUMonitor</a></li>
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