Jeroen Ritmeijer

Performance monitoring PocketPC applications

Even though I am not officially a developer anymore, every once in a while I like to get my hands dirty and develop something that solves a problem that the developers in my company are struggling with. Today the problem is performance monitoring a PocketPC / Windows mobile 1st & 2nd edition / Windows CE (etc. etc.) device.

Sure there are some utilities that allow you to ‘trace’ what is going on in your .net CF application or show you the current status of your battery, but few, if any, allow a combination of statistics to be logged and analysed across all running applications in real time.

To solve this problem I developed a new product aptly, or badly, named Perfy, which is a universal framework that allows you to quickly expose anything as a standard windows performance counter by writing a simple plug-in. The first plug-in I wrote exposes a number of key Windows CE statistics such as available memory, remaining battery life, remaining backup battery life etc without needing to install anything on the PocketPC device, which minimises the Uncertainty Principle ;-)

At the time I wrote this application the development team was struggling with 2 problems; evaluating the battery life of a number of hardware platforms under different circumstances (WiFi, Bluetooth, backlight etc) and tracking down a memory leak in our popular GolfMate application.

The first task was now easy, just run Perfy, start the Windows Performance monitor, add a counter for Windows CE Counters / % Remaining battery life and either visually inspect the results over time or log it all to a CSV file for Graphing in Excel. The outcome was very interesting, some manufacturers who shall remain nameless quoted us with a battery life of 27 hours while in the real world it was less than 6, imagine that on the 17th hole, bye bye scores.

After some experimenting, after all Perfy makes this task easy, we were able to select a suitable hardware platform (17 hours of battery!!) and move on to the next task.

The second task, tracking down a small memory and performance leak, was a bit more difficult as the GolfMate continuously runs 2 Compact Framework applications as well as a C++ application that hosts the Flash based user interface in the Macromedia Flash 6 ActiveX control. Pfew, quite a mouth full…

Again, using Perfy and the Windows CE Counters / Available Physical Memory performance counter we were able to track down using a process of elimination, AKA the Art of Deduction, which component was leaking. For those who are interested one of the threads dealing with the Bluetooth based GPS device was restarted at an interval even when the previous thread had not finished due to a blocking Bluetooth connection. This all added up over time and caused a resource leak.

I will publish some information in the future about how to write a plug-in for Perfy to expose your own counters. The next set of counters I plan to add are the ones for my multi meter that can expose interesting data such as a unit’s temperature and charging voltage to the PC over RS232.