A minimal profiling module

tiny_timer.py

# Credits 2020-2022 to Élie Michel <elie.michel@exppad.com>
# Released in Public Domain
#
# The Software is provided "as is", without warranty of any kind, express or
# implied, including but not limited to the warranties of merchantability,
# fitness for a particular purpose and non-infringement. In no event shall the
# authors or copyright holders be liable for any claim, damages or other
# liability, whether in an action of contract, tort or otherwise, arising
# from, out of or in connection with the software or the use or other dealings
# in the Software.

from math import sqrt
import time
from collections import defaultdict

# -------------------------------------------------------------------

class Timer():
    def __init__(self):
        self.start = time.perf_counter()

    def ellapsed(self):
        return time.perf_counter() - self.start

# -------------------------------------------------------------------

class ProfilingCounter:
    def __init__(self):
        self.reset()

    def average(self):
        if self.sample_count == 0:
            return 0
        else:
            return self.accumulated / self.sample_count

    def stddev(self):
        if self.sample_count == 0:
            return 0
        else:
            avg = self.average()
            var = self.accumulated_sq / self.sample_count - avg * avg
            return sqrt(max(0, var))

    def add_sample(self, value):
        if hasattr(value, 'ellapsed'):
            value = value.ellapsed()
        self.sample_count += 1
        self.accumulated += value
        self.accumulated_sq += value * value

    def reset(self):
        self.sample_count = 0
        self.accumulated = 0.0
        self.accumulated_sq = 0.0

    def summary(self):
        """returns something like XXms (±Xms, X samples)"""
        return (
            f"{self.average()*1000.:.03}ms " +
            f"(±{self.stddev()*1000.:.03}ms, " +
            f"{self.sample_count} samples)"
        )

# -------------------------------------------------------------------

profiling_counters = defaultdict(ProfilingCounter)