def __init__(self, _time, milliseconds, bucket_numbers,
bucket_data_length, enabled):
self.time = _time
self.milliseconds = milliseconds
self.buckets = BucketCircular(bucket_numbers)
self.bucket_numbers = bucket_numbers
self.bucket_data_length = bucket_data_length
self.enabled = enabled
self.snapshot = PercentileSnapshot(0)
self._new_bucket_lock = RLock()
class RollingPercentile(object):
def __init__(self, _time, milliseconds, bucket_numbers,
bucket_data_length, enabled):
self.time = _time
self.milliseconds = milliseconds
self.buckets = BucketCircular(bucket_numbers)
self.bucket_numbers = bucket_numbers
self.bucket_data_length = bucket_data_length
self.enabled = enabled
self.snapshot = PercentileSnapshot(0)
self._new_bucket_lock = RLock()
def buckets_size_in_milliseconds(self):
return self.milliseconds / self.bucket_numbers
def current_bucket(self):
current_time = self.time.current_time_in_millis()
current_bucket = self.buckets.peek_last()
if current_bucket is not None and current_time < (current_bucket.window_start + self.buckets_size_in_milliseconds()):
return current_bucket
with self._new_bucket_lock:
# If we didn't find the current bucket above, then we have to
# create one.
if self.buckets.peek_last() is None:
new_bucket = Bucket(current_time, self.bucket_data_length)
self.buckets.add_last(new_bucket)
return new_bucket
else:
for i in range(self.bucket_numbers):
last_bucket = self.buckets.peek_last()
if current_time < (last_bucket.window_start + self.buckets_size_in_milliseconds()):
return last_bucket
elif current_time - (last_bucket.window_start + self.buckets_size_in_milliseconds()) > self.milliseconds:
self.reset()
return self.current_bucket()
else:
all_buckets = [b for b in self.buckets]
self.buckets.add_last(Bucket(last_bucket.window_start + self.buckets_size_in_milliseconds(), self.bucket_data_length))
self.snapshot = PercentileSnapshot(*all_buckets)
return self.buckets.peek_last()
# we didn't get the lock so just return the latest bucket while
# another thread creates the next one
current_bucket = self.buckets.peek_last()
if current_bucket is not None:
return current_bucket
else:
# The rare scenario where multiple threads raced to create the
# very first bucket wait slightly and then use recursion while
# the other thread finishes creating a bucket
time.sleep(5)
self.current_bucket()
def add_value(self, *values):
''' Add value (or values) to current bucket.
'''
if not self.enabled:
return
for value in values:
self.current_bucket().data.add_value(value)
def percentile(self, percentile):
if not self.enabled:
return -1
# Force logic to move buckets forward in case other requests aren't
# making it happen
self.current_bucket()
# Fetch the current snapshot
return self.current_percentile_snapshot().percentile(percentile)
def current_percentile_snapshot(self):
return self.snapshot
def mean(self):
if not self.enabled:
return -1
# Force logic to move buckets forward in case other requests aren't
# making it happen
self.current_bucket()
# Fetch the current snapshot
return self.current_percentile_snapshot().mean()