def check_stats_change()

in testsuite/driver/perf_notes.py [0:0]

• 35 lines of code
• 18 McCabe index (conditional complexity)

def check_stats_change(actual, baseline, tolerance_dev, allowed_perf_changes = {}, force_print = False):
    expected_val = baseline.perfStat.value
    full_name = actual.test + ' (' + actual.way + ')'

    lowerBound = trunc(           int(expected_val) * ((100 - float(tolerance_dev))/100))
    upperBound = trunc(0.5 + ceil(int(expected_val) * ((100 + float(tolerance_dev))/100)))

    actual_dev = round(((float(actual.value) * 100)/ int(expected_val)) - 100, 1)

    # Find the direction of change.
    change = MetricChange.NoChange
    if actual.value < lowerBound:
        change = MetricChange.Decrease
    elif actual.value > upperBound:
        change = MetricChange.Increase

    # Is the change allowed?
    allowed_change_directions =  [MetricChange.NoChange] + [ allow_stmt['direction']
            for allow_stmt in allowed_perf_changes.get(actual.test, [])

            # List of metrics are not specified or the metric is in the list of metrics.
            if not allow_stmt['metrics'] or actual.metric in allow_stmt['metrics']

            # way/test are not specified, or match the actual way/test.
            if ((not 'way'      in allow_stmt['opts'].keys()) or actual.way      == allow_stmt['opts']['way'])
            if ((not 'test_env' in allow_stmt['opts'].keys()) or actual.test_env == allow_stmt['opts']['test_env'])
        ]
    change_allowed = change in allowed_change_directions

    # Print errors and create pass/fail object.
    result = passed()
    if not change_allowed:
        error = change + ' from ' + baseline.perfStat.test_env + \
                ' baseline @ HEAD~' + str(baseline.commitDepth)
        print(actual.metric, error + ':')
        result = failBecause('stat ' + error, tag='stat')

    if not change_allowed or force_print:
        length = max(len(str(x)) for x in [expected_val, lowerBound, upperBound, actual.value])

        def display(descr, val, extra):
            print(descr, str(val).rjust(length), extra)

        display('    Expected    ' + full_name + ' ' + actual.metric + ':', expected_val, '+/-' + str(tolerance_dev) + '%')
        display('    Lower bound ' + full_name + ' ' + actual.metric + ':', lowerBound, '')
        display('    Upper bound ' + full_name + ' ' + actual.metric + ':', upperBound, '')
        display('    Actual      ' + full_name + ' ' + actual.metric + ':', actual.value, '')
        if actual.value != expected_val:
            display('    Deviation   ' + full_name + ' ' + actual.metric + ':', actual_dev, '%')

    return (change, result)