def get_cpu_usage(cr):
time.sleep(STABILIZATION_DURATION)
cpu_usage_start = site_utils.get_cpu_usage()
time.sleep(MEASUREMENT_DURATION)
cpu_usage_end = site_utils.get_cpu_usage()
return site_utils.compute_active_cpu_time(cpu_usage_start,
cpu_usage_end) * 100
def compute_active_cpu_time(self, cpu_usage_start, cpu_usage_end):
"""Computes the fraction of CPU time spent non-idling.
This function should be invoked using before/after values from calls to
get_cpu_usage().
"""
return site_utils.compute_active_cpu_time(cpu_usage_start,
cpu_usage_end)
def get_cpu_usage(self):
"""Computes current cpu usage in percentage.
@returns percentage cpu used as a float.
"""
cpu_usage_start = site_utils.get_cpu_usage()
time.sleep(MEASUREMENT_DURATION)
cpu_usage_end = site_utils.get_cpu_usage()
return site_utils.compute_active_cpu_time(cpu_usage_start,
cpu_usage_end) * 100
def test_cpu_usage(self):
"""
Runs the video cpu usage test.
@param local_path: the path to the video file.
@returns a dictionary that contains the test result.
"""
cpu_usage_start = site_utils.get_cpu_usage()
time.sleep(MEASUREMENT_DURATION)
cpu_usage_end = site_utils.get_cpu_usage()
return site_utils.compute_active_cpu_time(cpu_usage_start,
cpu_usage_end) * 100
def _get_cpu_usage(self):
"""Compute percent CPU in active use over the sample interval.
Note: This method introduces a sleep period into the test, equal to
90% of the sample interval.
@returns float of percent active use of CPU.
"""
# Time between measurements is ~90% of the sample interval.
measurement_time_delta = SAMPLE_INTERVAL * 0.90
cpu_usage_start = site_utils.get_cpu_usage()
time.sleep(measurement_time_delta)
cpu_usage_end = site_utils.get_cpu_usage()
return site_utils.compute_active_cpu_time(cpu_usage_start,
cpu_usage_end) * 100