[Haskell-cafe] Need pointer to explain CPU usage

Hello List, I have a tiny scotty-based application, which when compiled and started in profiling mode, consumes 10x CPU it does in normal mode. Interestingly, if I fire a request on the app, CPU usage drops to minimal after finishing the request for a while. But after a few minutes it starts consuming 10x CPU again. First I would have suspected scotty, however collecting time profiling info with -p, -P or -Pa doesn't reveal much. That still not rules scotty out however. To make matters worse, I inspect strange time profiling tick count I can't explain - the .prof file says "2 ticks @ 1000 us", while the application was clearly running idle for a good few seconds. Any ideas what am I missing? Thanks, Robin