X-Git-Url: https://gerrit.fd.io/r/gitweb?a=blobdiff_plain;f=resources%2Flibraries%2Fpython%2FMLRsearch%2FMeasurementDatabase.py;fp=resources%2Flibraries%2Fpython%2FMLRsearch%2FMeasurementDatabase.py;h=2f601d626000e0b51299c58c66570e0bb9a13cd1;hb=b6fbffad32515ccf94404680cb5280c2cb561af5;hp=0000000000000000000000000000000000000000;hpb=adf5f13886e8bdd4fb224f12f10d731cadf698f3;p=csit.git diff --git a/resources/libraries/python/MLRsearch/MeasurementDatabase.py b/resources/libraries/python/MLRsearch/MeasurementDatabase.py new file mode 100644 index 0000000000..2f601d6260 --- /dev/null +++ b/resources/libraries/python/MLRsearch/MeasurementDatabase.py @@ -0,0 +1,157 @@ +# Copyright (c) 2021 Cisco and/or its affiliates. +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at: +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + +"""Module defining MeasurementDatabase class.""" + +from .ReceiveRateInterval import ReceiveRateInterval +from .PerDurationDatabase import PerDurationDatabase + + +class MeasurementDatabase: + """A structure holding measurement results. + + The implementation uses a dict from duration values + to PerDurationDatabase instances. + + Several utility methods are added, accomplishing tasks useful for MLRsearch. + + This class contains the "find tightest bounds" parts of logic required + by MLRsearch. One exception is lack of any special handling for maximal + or minimal rates. + """ + + def __init__(self, measurements): + """Store measurement results in per-duration databases. + + TODO: Move processing to a factory method, + keep constructor only to store (presumably valid) values. + + If the measurements argument contains is a dict, + the constructor assumes it contains the processed databases. + + :param measurements: The measurement results to store. + :type measurements: Iterable[ReceiveRateMeasurement] + """ + if isinstance(measurements, dict): + self.data_for_duration = measurements + else: + self.data_for_duration = dict() + # TODO: There is overlap with add() code. Worth extracting? + for measurement in measurements: + duration = measurement.duration + if duration in self.data_for_duration: + self.data_for_duration[duration].add(measurement) + else: + self.data_for_duration[duration] = PerDurationDatabase( + duration, [measurement] + ) + durations = sorted(self.data_for_duration.keys()) + self.current_duration = durations[-1] if duration else None + self.previous_duration = durations[-2] if len(durations) > 1 else None + + def __repr__(self): + """Return string executable to get equivalent instance. + + :returns: Code to construct equivalent instance. + :rtype: str + """ + return f"MeasurementDatabase(measurements={self.data_for_duration!r})" + + def set_current_duration(self, duration): + """Remember what MLRsearch considers the current duration. + + Setting the same duration is allowed, setting smaller is not allowed. + + :param duration: Target trial duration of current phase, in seconds. + :type duration: float + :raises ValueError: If the duration is smaller than previous. + """ + if duration < self.current_duration: + raise ValueError( + f"Duration {duration} shorter than current duration" + f" {self.current_duration}" + ) + if duration > self.current_duration: + self.previous_duration = self.current_duration + self.current_duration = duration + self.data_for_duration[duration] = PerDurationDatabase( + duration, list() + ) + # Else no-op. + + def add(self, measurement): + """Add a measurement. Duration has to match the set one. + + :param measurement: Measurement result to add to the database. + :type measurement: ReceiveRateMeasurement + """ + duration = measurement.duration + if duration != self.current_duration: + raise ValueError( + f"{measurement!r} duration different than" + f" {self.current_duration}" + ) + self.data_for_duration[duration].add(measurement) + + def get_bounds(self, ratio): + """Return 6 bounds: lower/upper, current/previous, tightest/second. + + Second tightest bounds are only returned for current duration. + None instead of a measurement if there is no measurement of that type. + + The result cotains bounds in this order: + 1. Tightest lower bound for current duration. + 2. Tightest upper bound for current duration. + 3. Tightest lower bound for previous duration. + 4. Tightest upper bound for previous duration. + 5. Second tightest lower bound for current duration. + 6. Second tightest upper bound for current duration. + + :param ratio: Target ratio, valid has to be lower or equal. + :type ratio: float + :returns: Measurements acting as various bounds. + :rtype: 6-tuple of Optional[PerDurationDatabase] + """ + cur_lo1, cur_hi1, pre_lo, pre_hi, cur_lo2, cur_hi2 = [None] * 6 + duration = self.current_duration + if duration is not None: + data = self.data_for_duration[duration] + cur_lo1, cur_hi1, cur_lo2, cur_hi2 = data.get_valid_bounds(ratio) + duration = self.previous_duration + if duration is not None: + data = self.data_for_duration[duration] + pre_lo, pre_hi, _, _ = data.get_valid_bounds(ratio) + return cur_lo1, cur_hi1, pre_lo, pre_hi, cur_lo2, cur_hi2 + + def get_results(self, ratio_list): + """Return list of intervals for given ratios, from current duration. + + Attempt to construct valid intervals. If a valid bound is missing, + use smallest/biggest target_tr for lower/upper bound. + This can result in degenerate intervals. + + :param ratio_list: Ratios to create intervals for. + :type ratio_list: Iterable[float] + :returns: List of intervals. + :rtype: List[ReceiveRateInterval] + """ + ret_list = list() + current_data = self.data_for_duration[self.current_duration] + for ratio in ratio_list: + lower_bound, upper_bound, _, _, _, _ = self.get_bounds(ratio) + if lower_bound is None: + lower_bound = current_data.measurements[0] + if upper_bound is None: + upper_bound = current_data.measurements[-1] + ret_list.append(ReceiveRateInterval(lower_bound, upper_bound)) + return ret_list