"""HPO algorithm abstract class."""
# Copyright (C) 2022 Intel Corporation
#
# 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.
import json
import tempfile
from abc import ABC, abstractmethod
from enum import IntEnum
from typing import Any, Dict, List, Optional, Union
from otx.hpo.search_space import SearchSpace
from otx.hpo.utils import check_mode_input, check_positive
from otx.utils.logger import get_logger
logger = get_logger()
class HpoBase(ABC):
"""Abstract class for HPO algorithms.
This implements class for HPO algorithm base.
Only common methods are implemented but not core algorithm of HPO.
Args:
search_space (Dict[str, Dict[str, Any]]): hyper parameter search space to find.
save_path (Optional[str]): path where result of HPO is saved.
mode (str, optinal): One of {min, max}. Determines whether objective is
minimizing or maximizing the metric attribute.
num_trials (Optional[int]): How many training to conduct for HPO.
num_workers (int): How many trains are executed in parallel.
num_full_iterations (int): epoch for traninig after HPO.
non_pure_train_ratio (float): ratio of validation time to (train time + validation time)
full_dataset_size (int): train dataset size
metric (str): Which score metric to use.
expected_time_ratio (Optional[Union[int, float]]): Time to use for HPO.
If HPO is configured automatically,
HPO use time about exepected_time_ratio *
train time after HPO times.
maximum_resource (Optional[Union[int, float]]): Maximum resource to use for training each trial.
subset_ratio (Optional[Union[float, int]]): ratio to how many train dataset to use for each trial.
The lower value is, the faster the speed is.
But If it's too low, HPO can be unstable.
min_subset_size (int) : Minimum size of subset. Default value is 500.
resume (bool): resume flag decide to use previous HPO results.
If HPO completed, you can just use optimized hyper parameters.
If HPO stopped in middle, you can resume in middle.
prior_hyper_parameters (Optional[Union[Dict, List[Dict]]]) = Hyper parameters to try first.
acceptable_additional_time_ratio (Union[float, int]) = Decide how much additional time can be acceptable.
"""
# pylint: disable=too-many-instance-attributes
def __init__(
self,
search_space: Dict[str, Dict[str, Any]],
save_path: Optional[str] = None,
mode: str = "max",
num_trials: Optional[int] = None,
num_workers: int = 1,
num_full_iterations: Union[int, float] = 1,
non_pure_train_ratio: float = 0.2,
full_dataset_size: int = 0,
metric: str = "mAP",
expected_time_ratio: Optional[Union[int, float]] = None,
maximum_resource: Optional[Union[int, float]] = None,
subset_ratio: Optional[Union[float, int]] = None,
min_subset_size: int = 500,
resume: bool = False,
prior_hyper_parameters: Optional[Union[Dict, List[Dict]]] = None,
acceptable_additional_time_ratio: Union[float, int] = 1.0,
):
# pylint: disable=too-many-arguments, too-many-locals
check_mode_input(mode)
check_positive(full_dataset_size, "full_dataset_size")
check_positive(num_full_iterations, "num_full_iterations")
if not 0 < non_pure_train_ratio <= 1:
raise ValueError(
"non_pure_train_ratio should be greater than 0 and lesser than or equal to 1."
f" Your value is {subset_ratio}"
)
if maximum_resource is not None:
check_positive(maximum_resource, "maximum_resource")
if num_trials is not None:
check_positive(num_trials, "num_trials")
check_positive(num_workers, "num_workers")
if subset_ratio is not None:
if not 0 < subset_ratio <= 1:
raise ValueError(
"subset_ratio should be greater than 0 and lesser than or equal to 1."
f" Your value is {subset_ratio}"
)
if save_path is None:
save_path = tempfile.mkdtemp(prefix="OTX-hpo-")
self.save_path = save_path
self.search_space = SearchSpace(search_space)
self.mode = mode
self.num_trials = num_trials
self.num_workers = num_workers
self.num_full_iterations = num_full_iterations
self.non_pure_train_ratio = non_pure_train_ratio
self.full_dataset_size = full_dataset_size
self.expected_time_ratio = expected_time_ratio
self.maximum_resource: Optional[Union[int, float]] = maximum_resource
self.subset_ratio = subset_ratio
self.min_subset_size = min_subset_size
self.resume = resume
self.hpo_status: dict = {}
self.metric = metric
self.acceptable_additional_time_ratio = acceptable_additional_time_ratio
if prior_hyper_parameters is None:
prior_hyper_parameters = []
elif isinstance(prior_hyper_parameters, dict):
prior_hyper_parameters = [prior_hyper_parameters]
self.prior_hyper_parameters = prior_hyper_parameters
@abstractmethod
def print_result(self):
"""Print a HPO algorithm result."""
raise NotImplementedError
@abstractmethod
def save_results(self):
"""Save a HPO algorithm result."""
raise NotImplementedError
@abstractmethod
def is_done(self):
"""Check whether HPO algorithm is done."""
raise NotImplementedError
@abstractmethod
def get_next_sample(self):
"""Get next sample to train."""
raise NotImplementedError
@abstractmethod
def auto_config(self):
"""Configure HPO algorithm automatically."""
raise NotImplementedError
@abstractmethod
def get_progress(self):
"""Get current progress of HPO algorithm."""
raise NotImplementedError
@abstractmethod
def report_score(self, score, resource, trial_id, done):
"""Report a score to HPO algorithm."""
raise NotImplementedError
@abstractmethod
def get_best_config(self):
"""Get best config of HPO algorithm."""
raise NotImplementedError
class Trial:
"""Trial to train with given hyper parameters.
Args:
trial_id (Any): Trial id.
configuration (Dict): Configuration to train with.
train_environment (Optional[Dict], optional): Train environment for the trial. Defaults to None.
"""
def __init__(self, trial_id: Any, configuration: Dict, train_environment: Optional[Dict] = None):
self._id = trial_id
self._configuration = configuration
self.score: Dict[Union[float, int], Union[float, int]] = {}
self._train_environment = train_environment
self._iteration = None
self.status: TrialStatus = TrialStatus.READY
self._done = False
@property
def id(self):
"""Trial id."""
return self._id
@property
def configuration(self):
"""Configuration to train with."""
return self._configuration
@property
def iteration(self):
"""Iteration to use for training."""
return self._iteration
@iteration.setter
def iteration(self, val):
"""Setter for iteration."""
check_positive(val, "iteration")
self._iteration = val
if self.get_progress() < val:
self._done = False
@property
def train_environment(self):
"""Train environment for the trial."""
return self._train_environment
def get_train_configuration(self) -> Dict[str, Any]:
"""Get configurations needed to trian."""
self._configuration["iterations"] = self.iteration
return {"id": self.id, "configuration": self.configuration, "train_environment": self.train_environment}
def register_score(self, score: Union[int, float], resource: Union[int, float]):
"""Register score to the trial.
Args:
score (Union[int, float]): Score to register.
resource (Union[int, float]): Resource used to get score. It should be positive.
"""
check_positive(resource, "resource")
self.score[resource] = score
def get_best_score(
self, mode: str = "max", resource_limit: Optional[Union[float, int]] = None
) -> Optional[Union[float, int]]:
"""Get best score of the trial.
Args:
mode (str, optional): Decide which is better between highest score or lowest score. Defaults to "max".
resource_limit (Optional[Union[float, int]], optional): Find a best score among the score at resource
lower than this value. Defaults to None.
Returns:
Optional[Union[float, int]]: Best score. If there is no score, return None.
"""
check_mode_input(mode)
if resource_limit is None:
scores = self.score.values()
else:
scores = [val for key, val in self.score.items() if key <= resource_limit] # type: ignore
if len(scores) == 0:
return None
if mode == "max":
return max(scores)
return min(scores)
def get_progress(self) -> Union[float, int]:
"""Get a progress of the trial.
Returns:
Union[float, int]: How many resource is used for the trial.
"""
if len(self.score) == 0:
return 0
return max(self.score.keys())
def save_results(self, save_path: str):
"""Save a result in the 'save_path'.
Args:
save_path (str): Path where to save a result.
"""
results = {
"id": self.id,
"configuration": self.configuration,
"train_environment": self.train_environment,
"score": self.score,
}
with open(save_path, "w", encoding="utf-8") as f:
json.dump(results, f)
def finalize(self):
"""Set done as True."""
if not self.score:
raise RuntimeError(f"Trial{self.id} didn't report any score but tries to be done.")
self._done = True
def is_done(self):
"""Check the trial is done."""
if self.iteration is None:
raise ValueError("iteration isn't set yet.")
return self._done or self.get_progress() >= self.iteration
[docs]
class TrialStatus(IntEnum):
"""Enum class for trial status."""
UNKNOWN = -1
READY = 0
RUNNING = 1
STOP = 2
CUDAOOM = 3
