def test_degradation_no_io(self):
'''
No disk IO when input fits in buffer
'''
buffer_size = 10
counters.reset_counter('load')
self.validate_group_by(xrange(buffer_size), buffer_size=buffer_size)
self.assertEqual(counters.get_counter('load'), 0, 'No disk IO')
def testBasic(self):
iterable = [{1: 2}, 'two', (3, 3, 3)]
fileIterable = FileBackedIterable(iterable)
fileIterator = iter(fileIterable)
counters.reset_counter('load')
for i in iterable:
assert fileIterator.hasMore()
iFile = next(fileIterator)
assert i == iFile
assert not fileIterator.hasMore()
self.assertEqual(counters.get_counter('load'), 3)
fileIterable.removeFile()
def test_degradation_linear(self):
'''
As the input size increases, the number of calls
to "load" (disk IO) increases linearly to the input size
'''
buffer_size = 10
input_size1 = 2*buffer_size
input_size2 = 10*buffer_size
counters.set_counter('item_buffer', settings.MAX_CHUNKS)
counters.reset_counter('load')
self.validate_group_by(xrange(input_size1), buffer_size=buffer_size)
load_to_input_size1 = 1.0*counters.get_counter('load') / input_size1
counters.reset_counter('load')
self.validate_group_by(xrange(input_size2), buffer_size=buffer_size)
load_to_input_size2 = 1.0*counters.get_counter('load') / input_size2
self.assertLess(input_size1, input_size2, 'test different input size')
self.assertLessEqual(load_to_input_size1, load_to_input_size2,
'#load is linear to input size %s %s' % (load_to_input_size1, load_to_input_size2))