67 lines
1.9 KiB
Python
67 lines
1.9 KiB
Python
import time
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def compute_precision(func):
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previous = func()
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precision = None
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points = 0
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min_points = 100
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while points < min_points:
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value = func()
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if value == previous:
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continue
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dt = value - previous
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previous = value
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if precision is not None:
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precision = min(precision, dt)
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else:
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precision = dt
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if precision < 10e-6:
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min_points = 5000
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elif precision < 1e-3:
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min_points = 1000
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points += 1
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return dt
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def format_duration(dt):
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if dt >= 1e-3:
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return "%.0f ms" % (dt * 1e3)
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if dt >= 1e-6:
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return "%.0f us" % (dt * 1e6)
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else:
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return "%.0f ns" % (dt * 1e9)
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def test_clock(name, func):
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precision = compute_precision(func)
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print("%s:" % name)
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print("- precision in Python: %s" % format_duration(precision))
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clocks = ('clock', 'perf_counter', 'process_time')
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if hasattr(time, 'monotonic'):
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clocks.append('monotonic')
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clocks.append('time')
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for name in clocks:
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func = getattr(time, name)
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test_clock("%s()" % name, func)
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info = time.get_clock_info(name)
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if 'precision' in info:
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print("- announced precision: %s" % format_duration(info['precision']))
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print("- implementation: %s" % info['implementation'])
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print("- resolution: %s" % format_duration(info['resolution']))
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clock_ids = [name for name in dir(time) if name.startswith("CLOCK_")]
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for clock_id_text in clock_ids:
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clock_id = getattr(time, clock_id_text)
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name = 'clock_gettime(%s)' % clock_id_text
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def gettime():
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return time.clock_gettime(clock_id)
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try:
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gettime()
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except OSError as err:
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print("%s failed: %s" % (name, err))
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continue
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test_clock(name, gettime)
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precision = time.clock_getres(clock_id)
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print("- announced precision: %s" % format_duration(precision))
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