How profilers work - statistical profilers

stat_prof.py

import defaultdict
import time
import signal

SAMPLE_INTERVAL = 0.001 # seconds

def sample_stack(signum, frame):
    stack = []
    while frame:
        stack.append(frame.f_code.co_name)
        frame = frame.f_back
    stack_name = '-'.join(reversed(stack))
    stats[stack_name] += 1
    signal.setitimer(signal.ITIMER_PROF, SAMPLE_INTERVAL)

stats = defaultdict(int)
signal.signal(signal.SIGPROF, sample_stack)
signal.setitimer(signal.ITIMER_PROF, SAMPLE_INTERVAL)
start_time = time.time()

primes = get_primes(1000)

end_time = time.time()
signal.setitimer(signal.ITIMER_PROF, 0)