Inconsistent behaviour for RAM and CPU Monitoring

[Matyro]

Describe the bug
The Hardware CPU Module and the RAM Module show inconsistent behavior how the handle child processes.

While RAM uses the Memory of all child process

codecarbon/codecarbon/external/ram.py

Lines 288 to 298 in 66cc372

	def process_memory_GB(self):
	"""
	Property to compute the process's total memory usage in bytes.
	Returns:
	float: RAM usage (GB)
	"""
	children_memories = self._get_children_memories() if self._children else []
	main_memory = psutil.Process(self._pid).memory_info().rss
	memories = children_memories + [main_memory]
	return sum([m for m in memories if m] + [0]) / B_TO_GB

CPU Limits itself to the main process

codecarbon/codecarbon/external/hardware.py

Lines 247 to 253 in 66cc372

	elif self._tracking_mode == "process":
	cpu_load = self._process.cpu_percent(interval=0.5) / self._cpu_count
	power = self._tdp * cpu_load / 100
	logger.debug(
	f"CPU load {self._tdp} W and {cpu_load * 100:.1f}% => estimation of {power} W for process {self._pid}."
	)

Expected behavior
Similar behavior for booth, I would be in favor of having "process" and "process_tree" as option

Solution

Adding a "process_tree" option or exchanging the CPU Part with something similar to this:

elif self._tracking_mode == "process_tree":
            # Sum CPU percent for process and its children
            total_cpu_load = self._process.cpu_percent(interval=0.5)
            for child in self._process.children(recursive=True):
                try:
                    total_cpu_load += child.cpu_percent(interval=0.0)
                except (psutil.NoSuchProcess, psutil.AccessDenied):
                    continue
            cpu_load = total_cpu_load / self._cpu_count
            power = self._tdp * cpu_load / 100
            logger.debug(
                f"CPU load {self._tdp} W and {cpu_load * 100:.1f}% => estimation of {power} W for process tree {self._pid}."
            )

Cheers
Dominik

[benoit-cty]

Thanks, I have drafted a fix : #977