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Java Memory Profiling Simplified

As a typical Java developer I never monitored the memory usage of my application apart from following typical best practices like closing the connections, streams etc.. Recently we were struck with few issues in our JBoss servers that I had to dig in to the memory management.One of the best thing in java is that the developers are not required ...

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BTrace: hidden gem in Java developer toolbox

This post is about BTrace which I am considering as a hidden gem for Java developer. BTrace is a safe, dynamic tracing tool for the Java platform. BTrace can be used to dynamically trace a running Java program (similar to DTrace for OpenSolaris applications and OS). Shortly, the tool allows to inject tracing points without restarting or reconfiguring your Java ...

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Which Java thread consumes my CPU?

What do you do when your Java application consumes 100% of the CPU? Turns out you can easily find the problematic thread(s) using built-in UNIX and JDK tools. No profilers or agents required. For the purpose of testing we’ll use this simple program: public class Main { public static void main(String[] args) { new Thread(new Idle(), 'Idle').start(); new Thread(new Busy(), ...

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Java Thread at RUNNABLE state is not really running

Recently, I was doing an analysis/tuning on a Java application server installation in order to identify the bottlenecks and fix them. The most common action in such procedure (tuning) is to retrieve many Thread dumps, when system is on load. Please have in mind that heavy load (for some cases) may have side effects that they may lead us to ...

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Memory Access Patterns Are Important

In high-performance computing it is often said that the cost of a cache-miss is the largest performance penalty for an algorithm. For many years the increase in speed of our processors has greatly outstripped latency gains to main-memory. Bandwidth to main-memory has greatly increased via wider, and multi-channel, buses however the latency has not significantly reduced. To hide this latency ...

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Oracle Service Bus – Stuck Thread Case Study

java-interview-questions-answers

This case study describes the complete root cause analysis process of a stuck thread problem experienced with Oracle Service Bus 11g running on AIX 6.1 and IBM Java VM 1.6.  This article is also a great opportunity for you to improve your thread dump analysis skills and I highly recommend that you study and properly understand the following analysis approach. ...

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5 tips for proper Java Heap size

java-interview-questions-answers

Determination of proper Java Heap size for a production system is not a straightforward exercise. In my Java EE enterprise experience, I have seen multiple performance problem cases due to inadequate Java Heap capacity and tuning. This article will provide you with 5 tips that can help you determine optimal Java Heap size, as a starting point, for your current ...

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