diff options
author | Vratko Polak <vrpolak@cisco.com> | 2021-03-22 17:11:21 +0100 |
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committer | Vratko Polak <vrpolak@cisco.com> | 2021-03-22 17:11:21 +0100 |
commit | b6fbffad32515ccf94404680cb5280c2cb561af5 (patch) | |
tree | 6f16569781e3e3627589c6fff0d7a5be0410d3f3 /resources/libraries/python/MLRsearch/PerDurationDatabase.py | |
parent | adf5f13886e8bdd4fb224f12f10d731cadf698f3 (diff) |
MLRsearch: Support other than just two ratios
+ Change some method names and argument types:
+ Do not mention NDR and PDR, except as examples.
+ Return list of ReceiveRateInterval instead of NdrPdrResult.
+ The resulting intervals can be degenerate when hitting min/max rate.
+ Rename quantity name parts from "fraction" to "ratio".
+ Intervals are no longer tracked for each target ratio.
+ They are found dynamically from known results.
+ Add effective_loss_ratio field to avoid loss inversion effects.
+ Move some functions to separate files.
+ Bound search logic moved to MeasurementDatabase.py
+ ProgressState moved to its file.
+ WidthArithmetics.py holds small computation functions.
+ Use parameter expansion_coefficient instead of "doublings".
+ Do uneven bisect to save time when width is not power of two times goal.
+ Timeout now correctly tracked for the whole search,
not just the current phase.
+ Make logging (debug) function pluggable.
+ Added debug log messages for initial phase.
+ Do not mark as subclass if contructor signature differs.
+ Avoid re-measure on scale-limited (ASTF) profiles.
+ Remove outdated comments.
+ Bump copyright years.
Change-Id: I93f693b4f186f59030ee5ac21b78acc890109813
Signed-off-by: Vratko Polak <vrpolak@cisco.com>
Diffstat (limited to 'resources/libraries/python/MLRsearch/PerDurationDatabase.py')
-rw-r--r-- | resources/libraries/python/MLRsearch/PerDurationDatabase.py | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/resources/libraries/python/MLRsearch/PerDurationDatabase.py b/resources/libraries/python/MLRsearch/PerDurationDatabase.py new file mode 100644 index 0000000000..b069dd921a --- /dev/null +++ b/resources/libraries/python/MLRsearch/PerDurationDatabase.py @@ -0,0 +1,121 @@ +# 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 PerDurationDatabase class.""" + +import copy + + +class PerDurationDatabase: + """List-like structure holding measurement results for one duration. + + This is a building block for MeasurementDatabase. + + This class hold measurements for single target duration value only, + so the logic is quite simple. + + Several utility methods are added, accomplishing tasks useful for MLRsearch + (to be called by MeasurementDatabade). + """ + + def __init__(self, duration, measurements): + """Store (deep copy of) measurement results and normalize them. + + The results have to have the corresponding target duration, + and there should be no duplicate target_tr values. + Empty iterable (zero measurements) is an acceptable input. + + :param duration: All measurements have to have this target duration [s]. + :param measurements: The measurement results to store. + :type duration: float + :type measurements: Iterable[ReceiveRateMeasurement] + :raises ValueError: If duration does not match or if TR duplicity. + """ + self.duration = duration + self.measurements = [copy.deepcopy(meas) for meas in measurements] + self._normalize() + + def __repr__(self): + """Return string executable to get equivalent instance. + + :returns: Code to construct equivalent instance. + :rtype: str + """ + return ( + u"PerDurationDatabase(" + f"duration={self.duration!r}," + f"measurements={self.measurements!r})" + ) + + def _normalize(self): + """Sort by target_tr, fail on detecting duplicate target_tr. + + Also set effective loss ratios. + """ + measurements = self.measurements + measurements.sort(key=lambda measurement: measurement.target_tr) + # Detect duplicated TRs. + previous_tr = None + for measurement in measurements: + current_tr = measurement.target_tr + if current_tr == previous_tr: + raise ValueError( + u"Transmit rate conflict:" + f" {measurement!r} {previous_tr!r}" + ) + previous_tr = current_tr + # Update effective ratios. + ratio_previous = None + for measurement in measurements: + if ratio_previous is None: + ratio_previous = measurement.loss_ratio + measurement.effective_loss_ratio = ratio_previous + continue + ratio_previous = max(ratio_previous, measurement.loss_ratio) + measurement.effective_loss_ratio = ratio_previous + + def add(self, measurement): + """Add measurement and normalize. + + :param measurement: Measurement result to add to the database. + :type measurement: ReceiveRateMeasurement + """ + # TODO: We should deepcopy either everywhere or nowhere. + self.measurements.append(measurement) + self._normalize() + + def get_valid_bounds(self, ratio): + """Return None or a valid measurement for two tightest bounds. + + The validity of a measurement to act as a bound is determined + by comparing the argument ratio with measurement's effective loss ratio. + + Both lower and upper bounds are returned, both tightest and second + tightest. If some value is not available, None is returned instead. + + :param ratio: Target ratio, valid has to be lower or equal. + :type ratio: float + :returns: Tightest lower bound, tightest upper bound, + second tightest lower bound, second tightest upper bound. + :rtype: 4-tuple of Optional[ReceiveRateMeasurement] + """ + lower_1, upper_1, lower_2, upper_2 = None, None, None, None + for measurement in self.measurements: + if measurement.effective_loss_ratio > ratio: + if upper_1 is None: + upper_1 = measurement + continue + upper_2 = measurement + break + lower_1, lower_2 = measurement, lower_1 + return lower_1, upper_1, lower_2, upper_2 |