From fc4d5df676a67e63d21ded54099daff1927f00f1 Mon Sep 17 00:00:00 2001 From: Ned Batchelder Date: Sun, 1 Nov 2015 21:30:08 -0500 Subject: A test program assessing performance for issue #397 --- lab/bug397.py | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 56 insertions(+) create mode 100644 lab/bug397.py (limited to 'lab/bug397.py') diff --git a/lab/bug397.py b/lab/bug397.py new file mode 100644 index 00000000..4d72e908 --- /dev/null +++ b/lab/bug397.py @@ -0,0 +1,56 @@ +#!/usr/bin/env python +""" +Run this file two ways under coverage and see that the times are the same: + + $ coverage run lab/bug397.py slow + Runtime per example: 130.96 +/- 3.70 us + $ coverage run lab/bug397.py fast + Runtime per example: 131.34 +/- 4.48 us + +Written by David MacIver as part of +https://bitbucket.org/ned/coveragepy/issues/397/stopping-and-resuming-coverage-with + +""" +from __future__ import print_function + +import sys +import random +import time +import math + +if sys.argv[1] == "slow": + sys.settrace(sys.gettrace()) + +random.seed(1) + + +def hash_str(s): + h = 0 + for c in s: + h = (h * 31 + ord(c)) & (2 ** 64 - 1) + return h + +data = [ + hex(random.getrandbits(1024)) for _ in range(500) +] + +N_SAMPLES = 100 + + +def mean(xs): + xs = list(xs) + return sum(xs) / len(xs) + + +def sd(xs): + return math.sqrt(mean(x ** 2 for x in xs) - mean(xs) ** 2) + + +if __name__ == '__main__': + timing = [] + for _ in range(N_SAMPLES): + start = time.time() + for d in data: + hash_str(d) + timing.append(1000000 * (time.time() - start) / len(data)) + print("Runtime per example:", "%.2f +/- %.2f us" % (mean(timing), sd(timing))) -- cgit v1.2.1