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      -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="../xdiagnosticscollector/" title="-Xdiagnosticscollector" class="md-nav__link">
      -Xdiagnosticscollector
    </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="./" 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 md-nav__item--active">
    
    <input class="md-toggle md-nav__toggle" data-md-toggle="toc" type="checkbox" id="__toc">
    
      
      <label class="md-nav__link md-nav__link--active" for="__toc">
        -Xmx
      </label>
    
    <a href="./" title="-Xmx" class="md-nav__link md-nav__link--active">
      -Xmx
    </a>
    
      
<nav class="md-nav md-nav--secondary">
  
  
    <label class="md-nav__title" for="__toc">On this page ...</label>
    <ul class="md-nav__list" data-md-scrollfix>
      
        <li class="md-nav__item">
  <a href="#syntax" title="Syntax" class="md-nav__link">
    Syntax
  </a>
  
</li>
      
        <li class="md-nav__item">
  <a href="#examples" title="Examples" class="md-nav__link">
    Examples
  </a>
  
</li>
      
        <li class="md-nav__item">
  <a href="#see-also" title="See also" class="md-nav__link">
    See also
  </a>
  
</li>
      
      
    </ul>
  
</nav>
    
  </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="../xrdbginfo/" title="-Xrdbginfo" class="md-nav__link">
      -Xrdbginfo
    </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--nested">
    
      <input class="md-toggle md-nav__toggle" data-md-toggle="nav-9-6" type="checkbox" id="nav-9-6">
    
    <label class="md-nav__link" for="nav-9-6">
      JVM -XX: options
    </label>
    <nav class="md-nav" data-md-component="collapsible" data-md-level="2">
      <label class="md-nav__title" for="nav-9-6">
        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="../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="../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="../xxnosuballoc32bitmem/" title="-XXnosuballoc32bitmem" class="md-nav__link">
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<h1 id="-xms-xmx">-Xms / -Xmx</h1>
<p>These Oracle&reg; Hotspot&trade; options set the initial/minimum Java&trade; heap size, and the maximum heap size respectively. These options are recognized by the OpenJ9 VM.</p>
<p><i class="fa fa-pencil-square-o" aria-hidden="true"></i> <strong>Notes:</strong></p>
<ul>
<li>If you set <code>-Xms</code> &gt; <code>-Xmx</code>, the OpenJ9 VM fails with the message <code>-Xms too large for -Xmx</code>.</li>
<li>If you exceed the limit set by the <code>-Xmx</code> option, the OpenJ9 VM generates an <code>OutofMemoryError</code>.</li>
</ul>
<p>If you are allocating the Java heap with large pages, see also <a href="../xlp/">-Xlp</a> and
<a href="https://www.ibm.com/support/knowledgecenter/SSYKE2_8.0.0/com.ibm.java.vm.80.doc/docs/mm_gc_compressed_refs.html">More effective heap usage using compressed references</a>.</p>
<p>You can also use the <a href="../xmo/"><code>-Xmo</code></a> option (not supported by the balanced garbage collection policy):<br />
If the scavenger is enabled, <code>-Xms</code> &ge; <code>-Xmn</code> + <code>-Xmo</code><br />
If the scavenger is disabled, <code>-Xms</code> &ge; <code>-Xmo</code>  </p>
<h2 id="syntax">Syntax</h2>
<table>
<thead>
<tr>
<th>Setting</th>
<th>Effect</th>
<th>Default</th>
</tr>
</thead>
<tbody>
<tr>
<td><code>-Xms&lt;size&gt;</code></td>
<td>Set initial heap size</td>
<td>8 MB</td>
</tr>
<tr>
<td><code>-Xmx&lt;size&gt;</code></td>
<td>Set maximum heap size</td>
<td>25% of available memory (25 GB maximum)</td>
</tr>
</tbody>
</table>
<p>See <a href="../x_jvm_commands/">Using -X command-line options</a> for more information about the <code>&lt;size&gt;</code> parameter.<br />
See <a href="../openj9_defaults/">Default settings for the OpenJ9 VM</a> for more about default values.</p>
<h2 id="examples">Examples</h2>
<dl>
<dt><code>-Xms2m -Xmx64m</code></dt>
<dd>Heap starts at 2 MB and grows to a maximum of 64 MB.</dd>
<dt><code>-Xms100m -Xmx100m</code></dt>
<dd>Heap starts at 100 MB and never grows.</dd>
<dt><code>-Xms50m</code></dt>
<dd>Heap starts at 50 MB and grows to the default maximum.</dd>
<dt><code>-Xmx256m</code></dt>
<dd>Heap starts at default initial value and grows to a maximum of 256 MB.</dd>
</dl>
<h2 id="see-also">See also</h2>
<ul>
<li><a href="../xsoftmx/">-Xsoftmx (Set "soft" maximum Java heap size)</a></li>
</ul>
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