There are many profiler options to debug performance issues.
These can be enabled by supplying the following command-line option and are saved in the pprof directory:
go run . --profile=cpu
Available profilers:
cpu mem block goroutine trace thread mutex
You can export the profiler output with the following command:
go tool pprof --pdf ./OpenDiablo2 pprof/profiler.pprof > file.pdf
In game you can create a heap dump by pressing ~ and typing dumpheap. A heap.pprof is written to the pprof directory.
You may need to install Graphviz in order to convert the profiler output.