I have Erlang/OTP 19 [erts-8.3.5] and runtime_tools included in release, rel/reltool.config.script:  [tools, runtime_tools];, but when I trying using dbg I got 
error:  dbg:tracer().
** exception error: undefined function dbg:tracer/0 
Looks like dbg module is not included to my application
(ejabberd@localhost)4> m(dbg).
** exception error: undefined function dbg:module_info/0
I want use erlang easy profiler, that I successfully used on erl 16
Does anyone faced with this problem?