Working With Thread Logic : A Thread Dump Analysis Tool

Thread Dump analysis is key tool for analyzing the Performance issues and troubleshooting many Issues. Currently available tools like samurai says about the state of the Thread , they does not give detailed view of what a thread is doing. In most cases , they dont mention what was happening inside a Thread , whether they are critical...

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org.jboss.virtual.plugins.context.zip.zipentrycontext Issue in Jboss 5.0.0.GA

The application team was complaining that they are seeing a lot of Out Of Memory When they try to deploy the application more than 3 times. Now we Got the Heap Dump and checked the instances that were causing the heap To Full. I found out that "org.jboss.virtual.plugins.context.zip.zipentrycontext" are being loaded and causing the memory to fill. As The references of "org.jboss.virtual.plugins.context.zip.zipentrycontext"...

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Linux Core and Java JMAP

When Generating heap dumps jmap blocks, and with large heaps  this can take a very long time. In these cases it is often much faster to get a core and then run jmap to extract a heap dump from the core. It is typically best to create the heap dump on the same box where the core was created to avoid environment differences. So what is Core Dump? When a program terminated abnormally, the status of the program at the...

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Java Dumps

As a Production Support Guy ,I many times faced the out of Memory(OOM) Issues. Most of times I take a Thread dump, Heap Dump before doing any thing to the server. I analyze the dumps to find out the possible problems that caused the out of Memory. So what are these Dumps? Thread Dump, a Thread Dump is a log containing information about currently running threads inside the JVM Heap Dump, a Heap Dump is a log which...

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Muxer Threads

Many Of the Times when there is a Server Crash, We take a Thread dump and analyze the threads running. During that time we see many threads like these "ExecuteThread: '0' for queue: 'weblogic.socket.Muxer'" id=20 idx=0x68 tid=26709 prio=5 alive, in native, blocked, daemon     -- Blocked trying to get lock: java/lang/String@0x2b673d373c50[fat lock]     at jrockit/vm/Threads.waitForUnblockSignal()V(Native...

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JRocket vs. SUN JDK

 SUN JDK JRocket Uses Interpreter Interpreter interprets (executes) one line at a time from the source file. Such as PHP, Perl, other scripting languages The byte code is read and the translated into machine language, but these results are not saved in the memory. So every time even if the same method is run again and again, the JVM has to translate the code into machine language....

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