Embedded Debugging - Heap allocations

Hello everybody.
Has anyone tried to check the heap memory allocated in Pixhawk through the steps described in the following link?

make px4_sitl_default

Start jmavsim: ./Tools/jmavsim_run.sh -l

In another terminal, type:

cd build/px4_sitl_default/tmp/rootfs
export HEAPPROFILE=/tmp/heapprofile.hprof
export HEAP_PROFILE_TIME_INTERVAL=30
env LD_PRELOAD=/usr/lib/libtcmalloc.so PX4_SIM_MODEL=iris ../../bin/px4 ../../etc -s etc/init.d-posix/rcS
google-pprof --pdf ../src/firmware/posix/px4 /tmp/heapprofile.hprof.0001.heap > heap.pdf 

I have been trying for while, but I am not getting the heap.pdf file that should be the output after following this steps.

The Ubuntu terminal is stucked at “INFO [tone_alarm] notify negative” and there is no generation of a .pdf file as described.

I am using a Ubuntu 18.04 and PX4 V1.11.3.

Any comment will be welcomed.
Thanks

Paulo