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On April 30th, I am holding my public PhD defense.

Title

Three Pitfalls in Java Performance Evaluation.

Abstract

Executing a Java application is a complex matter when looking at what happens under the hood. The virtual machine (VM) runs the operations and takes care of class loading, compiling and optimising code, and garbage collection. Due to the interaction going on between the VM and the application and the non-determinism (e.g., due to time-based sampling) within the VM, no two executions will ever behave exactly alike. Performance analysis in this context should not be underestimated. In this dissertation, we uncover three pitfalls that have not been taken into consideration prior to this research.

All south-facing windows in the building where I work, have been equipped with sun screens. That is, against the outer wall, technicians have installed electrical sun screens. The idea is that by keeping the sun out during the summer (it can get really warm in here) we would somehow be saving energy. Yet the only air-conditioning devices are located in the server rooms. And they lie next to a cool hallway.

So, Ghent University has a new portal site for employees where they can get information regarding their paycheck, vacation, etc. So far, so good. The downside is the way the portal is advertised. First of all, UGent offers access to Windows applications via the Athena portal, where selecting an app in the browser launches e.g., a Citrix client to connect to the Windows server. Now, access to the new portal should go through Athena, so naturally I expected to meet a Windows application. And lo! I saw a Windows application starting. And it was ... the Internet Exploder (IE6).

On April 11th, 2008, after my internal PhD defense has taken place, two of my jury members will give a talk. If you are interested, can join us in the Jozef Plateauzaal in the Faculty of Engineering building, Plateaustraat 22, in Ghent. The first talk will be given by Matthias Hauswirth (University of Lugano, Switzerland) and is titled Observer Effect and Measurement Bias in Performance Measurement. The second talk is by Kathryn McKinley (University of Texas at Austin, USA), is titled Dynamic Bug Detection for Managed Languages.

While I think Michiel did a great job creating a flyer for a PhD public defense announcement/invitation in Microsoft Word, I think the world can use a Pages'08 template as well. So, based on Michiel's work, I present the flyer template.

I have submitted my PhD dissertation --- titled 'Three pitfalls in Java performance evaluation' --- to the Faculty of Engineering who convened on February 20th, 2008 and decided I was to be allowed to the first (internal) defense.

In the previous post, I mentioned that AFS denies access to your files when you do not have a token. This is still true, but apparently, you are able to launch both at and cron jobs using keytabs. This is a file, residing outside of the AFS realm, containing the password in some processed form (so the password is not available in clear text). Keytabs are created by the system administrator.

People at our department are often running jobs that take multiple days to complete. A good way to keep a job going is to use the screen tool. This allows one to keep running a shell even when not connected to the machine for a while, and to reconnect to that session when you login on the machine once more. Simple, lean and mean.