Which OS you are running the command ? Linux/MacOS/Windows ? Which JDK version ?
Arvind ________________________________ From: Ted Yu <[email protected]> To: [email protected] Sent: Friday, September 4, 2009 11:57:44 AM Subject: measuring memory usage Hi, I am using Hadoop 0.20 How can I get pass the exception below ? [had...@vh20 hadoop]$ jmap -heap 3837 Attaching to process ID 3837, please wait... sun.jvm.hotspot.debugger.NoSuchSymbolException: Could not find symbol "gHotSpotVMTypeEntryTypeNameOffset" in any of the known library names (libjvm.so, libjvm_g.so, gamma_g) at sun.jvm.hotspot.HotSpotTypeDataBase.lookupInProcess(HotSpotTypeDataBase. java:388) at sun.jvm.hotspot.HotSpotTypeDataBase.getLongValueFromProcess(HotSpotTypeD ataBase.java:369) at sun.jvm.hotspot.HotSpotTypeDataBase.readVMTypes(HotSpotTypeDataBase.java :102) at sun.jvm.hotspot.HotSpotTypeDataBase.<init>(HotSpotTypeDataBase.java:85) at sun.jvm.hotspot.bugspot.BugSpotAgent.setupVM(BugSpotAgent.java:568) at sun.jvm.hotspot.bugspot.BugSpotAgent.go(BugSpotAgent.java:494) at sun.jvm.hotspot.bugspot.BugSpotAgent.attach(BugSpotAgent.java:332) at sun.jvm.hotspot.tools.Tool.start(Tool.java:163) at sun.jvm.hotspot.tools.HeapSummary.main(HeapSummary.java:39) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.jav a:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessor Impl.java:43) at java.lang.reflect.Method.invoke(Method.java:616) at sun.tools.jmap.JMap.runTool(JMap.java:196) at sun.tools.jmap.JMap.main(JMap.java:128) Debugger attached successfully. sun.jvm.hotspot.tools.HeapSummary requires a java VM process/core! Thanks
