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  • 1.  WAS 7 Out Of Memory - issue with windows memory

    Posted Wed March 11, 2020 01:57 PM
      |   view attached
    Environment Details:
    - Windows Server 2008 (64bit) with 24 GB RAM
    - WebSphere 7.0.0.27
    JVM Heap Size :
    - Initial heap size: 4GB
    - Maximum Heap size: 6GB 
    - Generic JVM Arguments = "-Xgcpolicy:gencon "
    Facing An Issue OutOfMemoryError even we configured the JVM heap size as mentioned above the issue the java process can get more than 1GB RAM from the windows which is less than the assigned initial JVM memory, once WAS Java process reach 1GB RAM it's hanging.

    ------------------------------
    Ahmed
    ------------------------------

    Attachment(s)

    zip
    Logs_Srv01.zip   43 KB 1 version


  • 2.  RE: WAS 7 Out Of Memory - issue with windows memory

    Posted Wed March 11, 2020 05:51 PM
    Your OS is 64-bit.  Is your JVM also 64-bit ?
    execute:
    D:\IBM\WebSphere\AppServer\java\bin\java.exe -version
    and check output.
    •   Build: pwi3260sr12-20121025_01(SR12)  = 32-bit
    •   Build: pwa6460sr12-20121025_01(SR12) = 64-bit
    If this is 32-bit - than you cannot allocate more than ~1.2 GB
    If this is 64-bit  check created files:
    • Heap dump @ 'D:\IBM\WebSphere\AppServer\profiles\FGAESrv01\heapdump.20200310.141007.6760.0011.phd'
    • Java core  @ 'D:\IBM\WebSphere\AppServer\profiles\FGAESrv01\javacore.20200310.141003.6760.0010.txt'
    Check also size of Windows paging file.

    ------------------------------
    Sebastian Tylko
    ------------------------------

    Original Message


  • 3.  RE: WAS 7 Out Of Memory - issue with windows memory

    Posted Thu March 12, 2020 08:37 AM

    Hi Sebastian Tylko,
    Thank you for the replay; regarding your questions, find below the answers:
    Your OS is 64-bit.  Is your JVM also 64-bit?
    Yes Os is 64-bit, And  Java is  64-bit(see Attached )

    Heap dump (Attached both files)
    Also attached Windows paging file



    ------------------------------
    Ahmed
    alssarty@yahoo.com
    ------------------------------

    Attachment(s)

    zip
    JVMDUMP12-03-2020.zip   28.62 MB 1 version
    Original Message


  • 4.  RE: WAS 7 Out Of Memory - issue with windows memory

    Posted Thu March 12, 2020 08:58 AM
    Hello Ahmed,
    what you are showing us is the Java version used by windows but not the Java version used by WAS. But nevertheless your Java version is: J2RE 6.0 IBM J9 2.4 Windows Server 2008 amd64-64 build jvmwa6460-20080816_22093 (woww, almost 12 years old!).

    Please can you check the data you have uploaded? The javacore shows a min heap size of 50M (-Xms50m) and a max heap size of 256m ( -Xmx256m). And this 256m of Java heap were simply full. When opening the thread you were talking about 4GB initial heap. So there is a huge discrepancy here. Either the materials you sent are from another server or there is some significant misunderstanding.

    ------------------------------
    Hermann Huebler

    #IBMChampion
    ------------------------------

    Original Message


  • 5.  RE: WAS 7 Out Of Memory - issue with windows memory

    Posted Thu March 12, 2020 09:22 AM
      |   view attached
    This is The issue, we configured the WAS JVM as below:
    JVM Heap Size :
    - Initial heap size: 4GB
    - Maximum Heap size: 6GB 
    =============Server.xml===========
    <jvmEntries xmi:id="JavaVirtualMachine_1183122130078" verboseModeClass="false" verboseModeGarbageCollection="false" verboseModeJNI="false" initialHeapSize="‭4096‬" maximumHeapSize="6144" runHProf="false" hprofArguments="" debugMode="false" debugArgs="-agentlib:jdwp=transport=dt_socket,server=y,suspend=n,address=7777" genericJvmArguments="-Xgcpolicy:gencon -Xmn2048M" executableJarFileName="" disableJIT="false">
    <systemProperties xmi:id="Property_1" name="com.ibm.security.jgss.debug" value="off" required="false"/>
    <systemProperties xmi:id="Property_2" name="com.ibm.security.krb5.Krb5Debug" value="off" required="false"/>
    <systemProperties xmi:id="Property_1400137377353" name="com.ibm.websphere.webservices.http.maxConnection" value="500" required="false"/>
    </jvmEntries>v
    ================================
    before all working fine, since two days ago starts this behavior, the JVM can get more than 1GB even we configured the WAS to use initial Heap Size: 4GB. Java Proces check attached
    sadly it's an old system, but we are working to upgrade it.


    ------------------------------
    Ahmed
    alssarty@yahoo.com
    ------------------------------

    Original Message


  • 6.  RE: WAS 7 Out Of Memory - issue with windows memory

    Posted Thu March 12, 2020 10:01 AM
    Hello Ahmed,
    strange behavior what you are describing here. never saw that the application server starts with a different memory configuration as the one configured. The <jvmEntries> .... </jvmEntries> artifact you pasted clearly states that the server should start with -Xms4096M and -Xmx6144M but the javacore states something very different. There fore I'm wondering - are you sure that the javacore you uploaded before is from the server whose <jvmEntries> .... </jvmEntries> artifact you posted before? Does not look like that.

    What type of profile are you using? How many servers are configured under this profile? Is the correct server started? What do you get if you run a serverStatus.bat -all from the <profile_home>/bin?

    ------------------------------
    Hermann Huebler

    #IBMChampion
    ------------------------------

    Original Message


  • 7.  RE: WAS 7 Out Of Memory - issue with windows memory

    Posted Thu March 12, 2020 11:05 AM
    The strange thing is,  if you open the java core



    Are you sure the heap size is correct? From the dump seems no..






    ------------------------------
    Michele Buccarello
    ------------------------------

    Original Message


  • 8.  RE: WAS 7 Out Of Memory - issue with windows memory

    Posted Thu March 12, 2020 02:47 PM
    Without any doubts - you have max heap size set to 256m
    Your java process command line looks like:
    D:\IBM\WebSphere\AppServer/java/bin/java -Declipse.security -Dwas.status.socket=57809 -Dosgi.install.area=D:\IBM\WebSphere\AppServer -Dosgi.configuration.area=D:\IBM\WebSphere\AppServer\profiles\FGAESrv01/configuration -Dosgi.framework.extensions=com.ibm.cds,com.ibm.ws.eclipse.adaptors -Xshareclasses:name=webspherev70,nonFatal -Xscmx50M -Dsun.reflect.inflationThreshold=250 -Xbootclasspath/p:D:\IBM\WebSphere\AppServer/java/jre/lib/ext/ibmorb.jar;D:\IBM\WebSphere\AppServer/java/jre/lib/ext/ibmext.jar -classpath D:\IBM\WebSphere\AppServer\profiles\FGAESrv01/properties;D:\IBM\WebSphere\AppServer/properties;D:\IBM\WebSphere\AppServer/lib/startup.jar;D:\IBM\WebSphere\AppServer/lib/bootstrap.jar;D:\IBM\WebSphere\AppServer/lib/jsf-nls.jar;D:\IBM\WebSphere\AppServer/lib/lmproxy.jar;D:\IBM\WebSphere\AppServer/lib/urlprotocols.jar;D:\IBM\WebSphere\AppServer/deploytool/itp/batchboot.jar;D:\IBM\WebSphere\AppServer/deploytool/itp/batch2.jar;D:\IBM\WebSphere\AppServer/java/lib/tools.jar -Dibm.websphere.internalClassAccessMode=allow -Xms50m -Xmx256m -Xcompressedrefs -Dws.ext.dirs=D:\IBM\WebSphere\AppServer/java/lib […]

    (Line 26 of javacore.20200310.141003.6760.0010)
    You can confirm this in runtime by running:
     wmic process where "name like 'java.exe'" get commandline
    So it is  simple result of too small heap size.
    Server.xml sent by you is probably not used at all because other values from this file are also not set (e.g. -Xmn2048M)


    ------------------------------
    --
    Sebastian Tylko
    ------------------------------

    Original Message


  • 9.  RE: WAS 7 Out Of Memory - issue with windows memory

    Posted Thu March 12, 2020 04:31 AM
    Hello Ahmed,
    as Sebastian mentioned the first interesting question is is your Java 32Bit or 64Bit? Second - could you determine if this is a native OOM or a java heap OOM? The Javacore will help you to determine this. Do you have verbose:gc enabled? Any useful info there? Otherwise you need to check out the heapdump or the system-core - at least one of these should be generated during the OOM.

    Hope this helps - Hermann

    ------------------------------
    Hermann Huebler

    #IBMChampion
    ------------------------------

    Original Message


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