A counterintuitive relation between CPU and memory usage

Continuing my tests on low-end server environments, I recently set up a stress test of a load balanced tomcat webapp. Part of that tests consist in reducing the available memory for the webapp (JVM -Xmx switch) and see how low it could go before negatively affecting performance. It's common knowledge that once available memory runs … Continue reading A counterintuitive relation between CPU and memory usage →

Fixing screen brightness on a Samsung R60 and Ubuntu 10.04

Finally the day came when all the clean installs in the world will not make Vista any faster on my old Samsung R60 (1.5 Ghz Dualcore), so I figured it's time for a Linux distro. Apart from high power consumption (it's a known bug [1]) nearly everything worked as expected, left two things: I wasn't … Continue reading Fixing screen brightness on a Samsung R60 and Ubuntu 10.04 →

Running a java webapp in a VPS

The market is swarming with cheap Virtual Private Server (VPS) or Virtual Dedicated Server (VDS) offers [1] these days, and the specs don't look bad: you can get as much as 2GB RAM, 50GB storage space and a double core 2GHz CPU for less than 10$ / 8€ and nearly unlimited traffic. That's ideal for … Continue reading Running a java webapp in a VPS →

GWT RPC calls with Http GET method

GWT's RPC [1] component comes handy when communicating with java backends - it's like RMI restricted to asynchronous calls, however it escapes any attempts to cache server responses. This post discusses a moderately simple way of making RPC responses cacheable by Http proxies and browsers. I'm not going into the details of the RPC lifecycle … Continue reading GWT RPC calls with Http GET method →

When IE does not load images

Recently the need for a custom photo gallery surfaced in one of my GWT pet projects. While such an endeavour seems endless from an artistic point of view, the mechanics behind it - at least for my humble needs - were rather simple: the gallery widget will be given a list of image IDs for … Continue reading When IE does not load images →