I am looking for tips to profile the server side game loop of a Java program for CPU usage. I tried to use the TPTP plugin for Eclipse so far.
The problem I am having is that it is really slow. For example the startup of the server is normally done in less than a minute. But with the profiler it takes about 30 minutes.
Okay, I can enable the profiler only after the server is started, but I am still facing the problem that it is way too slow and using much CPU. So I am unable to connect a number of clients in order to reproduce the problem (even with disabled timeouts).
I already did some optimization based on no client at all and some very short profiling sessions with one client. This is, however, not really helpful because the game server is doing most of its work only if a player is in reach.
I am thankful for any tips on profiling for CPU usage.