[Python] How to get accurate process CPU and memory usage with python?

I am trying to create a process monitor but I am unable to get accurate results comparing my results to windows task manager.

I have been using psutil which seems to work fine when looking at the overall cpu and memory usage but doesn't appear to be very accurate for a single process. Memory usage is always higher than task manager and CPU it always random.

I am setting the process once on initialise with self.process = psutil.Process(self.pid) and then calling the below method once a second, the process in task manager is running at a constant 5.4% cpu usage and 130mb ram however the below code produces:

CPU: 12.5375
Memory 156459008
CPU: 0.0
Memory 156459008
CPU: 0.0
Memory 156459008
CPU: 0.0
Memory 156459008
CPU: 12.5375
Memory 156459008
CPU: 0.0
Memory 156459008
CPU: 0.0
Memory 156459008


Example code:

def process_info(self):
# I am calling this method twice because I read the first time gets ignored?
ignore_cpu = self.process.cpu_percent(interval=None) / psutil.cpu_count()
time.sleep(0.1)
process_cpu = self.process.cpu_percent(interval=None) / psutil.cpu_count()

# I also tried the below code but it was much worse than above
# for j in range(10):
# if j == 0:
# test_list = []
# p_cpu = self.process.cpu_percent(interval=0.1) / psutil.cpu_count()
# test_list.append(p_cpu)
# process_cpu = (sum(test_list)) / len(test_list)

# Memory is about 25mb higher than task manager
process_memory = self.process.memory_info().rss

print(f"CPU: {process_cpu}")
print(f"Memory: {process_memory}")


am I using psutil incorrectly or is there a more accurate way to grab the data?

Continue reading...