Log4j JMS Appender Performance Results

Posted by on July 10, 2012
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We recently came across a throughput issue with the Log4j JMS appender.  We were working with a client who was seeing throughput throttled as they went to high transaction rates on a Java web application.  Analysis of the thread dumps showed that the threads were synchronized on the Log4j Logger object.  We came across Ming Yuan’s blog […]

Using IBM MQ from Loadrunner Without the MQ Integration Feature

Posted by on December 14, 2010
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We have sometimes had a need to performence test a system by putting data onto an IBM MQ queue. Loadrunner has an option to integrate with IBM MQ, but an additional license is required. One solution we’ve used in the past is to write a custom Java class to access MQ, and use the Java […]

Monitoring Apache Server Status with JMeter

Posted by on September 21, 2010
Filed Under Performance Engineering | 8 Comments

We’ve been using JMeter to run some tests of a web application and wanted to monitor the Apache web server’s performance.  JMeter has a performance monitor for Tomcat, but not for the Apache web server.  We didn’t need JMeter to graph the data in the UI.  We just wanted a .CSV file that we could […]

Analyzing Memory Leaks in JRockit Behind a Firewall

Posted by on June 2, 2010
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We were recently trying to identify the source of a memory leak in a Weblogic Portal 10.3 application that was using JRockit build R27.6 on a RedHat 5 Linux 64 bit.  We were performance testing the application in a production-like environment.  The Weblogic servers were behind a firewall, and this created problems using tools to […]

Out of Memory Issues on 32 bit Windows

Posted by on April 23, 2010
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  I seem to be seeing more instances of Windows applications getting out of memory conditions on servers with 4 GB of RAM than I used to.  It seems that like the 640K limit of DOS in the early days, the 2 GB limit of process space on 32 bit Windows is more frequently an […]

Windows server crash using HP NC373i network adapter

Posted by on April 8, 2010
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  We were recently performance testing  an Internet banking web site for a major financial institution and encountered a blue screen crash on several Windows 2003 servers.  The solution took some investigation, so I’m posting this information to help others out who may encounter the same issue. The server configuration was HP BL460c – 2 quad […]

Using SiteScope 9.5 to Monitor Weblogic 10.3

Posted by on March 22, 2010
Filed Under Performance Engineering | 4 Comments

I recently tried to set up SiteScope 9.5 to monitor Weblogic Portal.  It was not a pleasant experience.  There are posts in various blogs about setting up JMX based monitoring of Weblogic.  Some of the information is older, inaccurate, or didn’t apply to my configuration.  So I’m consolidating the relevant information to my situation together here.   Note: HP […]

Think time in performance testing

Posted by on January 12, 2008
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Over the years executing/designing many successful performance testing scenarios and discussing with many performance testers & engineers, I have realized, in most of the performance testing approach, the ‘Think Time’ metric is taken for granted. Many testers record the application and keep the default Think time for test executions. What is a Think Time? Think […]

Open source GC viewer

Posted by on December 7, 2007
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One of the key aspects of tuning a java based web application is optimizing garbage collection. One tool that I have found that makes tuning GC easier is the open source tool GCViewer. This tool is very handy whether you are using a J2EE container like Tomcat, Weblogic or Websphere, or a standalone java application. […]