Source code for libai.utils.events

# coding=utf-8
# Copyright 2021 The OneFlow Authors. All rights reserved.
# Copyright (c) Facebook, Inc. and 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.


import datetime
import json
import logging
import os
import time
from collections import defaultdict
from contextlib import contextmanager

from libai.utils.file_io import PathManager
from libai.utils.history_buffer import HistoryBuffer

# --------------------------------------------------------
# References:
# https://github.com/facebookresearch/detectron2/blob/main/detectron2/utils/events.py
# --------------------------------------------------------


__all__ = [
    "get_event_storage",
    "JSONWriter",
    "CommonMetricPrinter",
    "EventStorage",
]

_CURRENT_STORAGE_STACK = []


[docs]def get_event_storage(): """ Returns: The :class:`EventStorage` object that's currently being used. Throw an error if no :class:`EventStorage` is currently enabled. """ assert len( _CURRENT_STORAGE_STACK ), "get_event_storage() has to be called inside a 'with EventStorage(...)' context!" return _CURRENT_STORAGE_STACK[-1]
class EventWriter: """ Base class for writers that obtain events from :class:`EventStorage` and process them. """ def write(self): raise NotImplementedError def close(self): pass
[docs]class JSONWriter(EventWriter): """ Write scalars to a json file. It saves scalars as one json per line (instead of a big json) for easy parsing. Example of parsing such a json file: :: $ cat metrics.json | jq -s '.[0:2]' [ { "data_time": 0.008433341979980469, "iteration": 19, "total_loss": 1.9228371381759644, "lr": 0.007173333333333333, "time": 0.25401854515075684 }, { "data_time": 0.007216215133666992, "iteration": 39, "total_loss": 1.282649278640747, "lr": 0.007706666666666667, "time": 0.2490077018737793 } ] $ cat metrics.json | jq '.loss_mask' 0.7126231789588928 0.689423680305481 0.6776131987571716 ... """ def __init__(self, json_file, window_size=20): """ Args: json_file (str): path to the json file. New data will be appended if the file exists. window_size (int): the window size of median smoothing for the scalars whose `smoothing_hint` are True. """ self._file_handle = PathManager.open(json_file, "a") self._window_size = window_size self._last_write = -1 def write(self): storage = get_event_storage() to_save = defaultdict(dict) for k, (v, iter) in storage.latest_with_smoothing_hint(self._window_size).items(): # keep scalars that have not been written if iter <= self._last_write: continue to_save[iter][k] = v if len(to_save): all_iters = sorted(to_save.keys()) self._last_write = max(all_iters) for itr, scalars_per_iter in to_save.items(): scalars_per_iter["iteration"] = itr self._file_handle.write(json.dumps(scalars_per_iter, sort_keys=True) + "\n") self._file_handle.flush() try: os.fsync(self._file_handle.fileno()) except AttributeError: pass def close(self): self._file_handle.close()
class TensorboardXWriter(EventWriter): """ Write all scalars to a tensorboard file """ def __init__(self, log_dir: str, window_size: int = 20, **kwargs): """ Args: log_dir (str): the directory to save the output events window_size (int): the scalars will be median-smoothed by this window size kwargs: other arguments passed to `tensorboardX.SummaryWriter(...)` """ self._window_size = window_size from tensorboardX import SummaryWriter self._writer = SummaryWriter(log_dir=log_dir, **kwargs) self._last_write = -1 def write(self): storage = get_event_storage() new_last_write = self._last_write for k, (v, iter) in storage.latest_with_smoothing_hint(self._window_size).items(): if iter > self._last_write: self._writer.add_scalar(k, v, iter) new_last_write = max(new_last_write, iter) self._last_write = new_last_write # TODO: add write image if len(storage._histograms) >= 1: for params in storage._histograms: self._writer.add_histogram_raw(**params) storage.clear_histograms() def close(self): if hasattr(self, "_writer"): # doesn't exist when the code fails at import self._writer.close()
[docs]class CommonMetricPrinter(EventWriter): """ Print **common** metrics to the terminal, including iteration time, ETA, memory, all losses, and the learning rate. It also applies smoothing using a window of 20 elements. It's meant to print common metrics in common ways. To print something in more customized ways, please implement a similar printer by yourself. """ def __init__(self, batch_size, max_iter): """ Args: max_iter (int): the maximum number of iterations to train. Used to compute ETA. """ self.logger = logging.getLogger(__name__) self._batch_size = batch_size self._max_iter = max_iter self._last_write = None def write(self): storage = get_event_storage() iteration = storage.iter consumed_samples = storage.samples if iteration == self._max_iter: # This hook only reports training progress (loss, ETA, etc) but not other data, # therefore do not write anything after training succeeds, even if this method # is called. return try: data_time = storage.history("data_time").avg(20) except KeyError: # they may not exist in the first few iterations (due to warmup) # or when SimpleTrainer is not used data_time = None eta_string = None try: iter_time = storage.history("time").global_avg() eta_seconds = storage.history("time").median(1000) * (self._max_iter - iteration - 1) storage.put_scalar("eta_seconds", eta_seconds, smoothing_hint=False) eta_string = str(datetime.timedelta(seconds=int(eta_seconds))) except KeyError: iter_time = None # estimate eta on our own - more noisy if self._last_write is not None: estimate_iter_time = (time.perf_counter() - self._last_write[1]) / ( iteration - self._last_write[0] ) eta_seconds = estimate_iter_time * (self._max_iter - iteration - 1) eta_string = str(datetime.timedelta(seconds=int(eta_seconds))) self._last_write = (iteration, time.perf_counter()) try: lr = "{:.2e}".format(storage.history("lr").latest()) except KeyError: lr = "N/A" max_mem_mb = None # NOTE: max_mem is parsed by grep in "dev/parse_results.sh" self.logger.info( " {eta}{iter} {sample} {losses} {time}{data_time} {tpt} lr: {lr} {memory}".format( eta=f"eta: {eta_string} " if eta_string else "", iter=f"iteration: {iteration}/{self._max_iter}", sample=f"consumed_samples: {consumed_samples}", losses=" ".join( [ "{}: {:.4g}".format(k, v.median(200)) for k, v in storage.histories().items() if "loss" in k ] ), time="time: {:.4f} s/iter ".format(iter_time) if iter_time is not None else "", data_time="data_time: {:.4f} s/iter".format(data_time) if data_time is not None else "", tpt="total_throughput: {:.2f} samples/s".format(self._batch_size / iter_time) if iter_time is not None else "", lr=lr, memory="max_mem: {:.0f}M".format(max_mem_mb) if max_mem_mb is not None else "", ) )
[docs]class EventStorage: """ The user-facing class that provides metric storage functionalities. In the future we may add support for storing / logging other types of data if needed. """ def __init__(self, start_iter=0): """ Args: start_iter (int): the iteration number to start with """ self._history = defaultdict(HistoryBuffer) self._smoothing_hints = {} self._latest_scalars = {} self._iter = start_iter self._batch_size = 0 self._current_prefix = "" self._vis_data = [] self._histograms = []
[docs] def put_image(self, img_name, img_tensor): """ Add an `img_tensor` associated with `img_name` to be shown on tensorboard. Args: img_name (str): The name of the image to put into tensorboard. img_tensor (flow.Tensor or numpy.array): An `uint8` or `float` Tensor of shape `[channel, height, width]` where `channel` is 3. The image format should be RGB. The elements in img_tensor can either have values in [0, 1] (float32) or [0, 255] (uint8). The `img_tensor` will be visualized in tensorboard. """ self._vis_data.append((img_name, img_tensor, self._iter))
[docs] def put_scalar(self, name, value, smoothing_hint=True): """ Add a scalar `value` to the `HistoryBuffer` associated with `name`. Args: smoothing_hint (bool): a 'hint' on whether this scalar is noisy and should be smoothed when logged. The hint will be accessible through :meth:`EventStorage.smoothing_hints`. A writer may ignore the hint and apply custom smoothing rule. It defaults to True because most scalars we save need to be smoothed to provide any useful signal. """ name = self._current_prefix + name history = self._history[name] value = float(value) history.update(value, self._iter) self._latest_scalars[name] = (value, self._iter) existing_hint = self._smoothing_hints.get(name) if existing_hint is not None: assert ( existing_hint == smoothing_hint ), "Scalar {} was put with a different smoothing_hint!".format(name) else: self._smoothing_hints[name] = smoothing_hint
[docs] def put_scalars(self, *, smoothing_hint=True, **kwargs): """ Put multiple scalars from keyword arguments. Example: .. code-block:: python storage.put_scalars(loss=my_loss, accuracy=my_accuracy, smoothing_hint=True) """ for k, v in kwargs.items(): self.put_scalar(k, v, smoothing_hint=smoothing_hint)
[docs] def history(self, name): """ Returns: HistoryBuffer: the scalar history for name """ ret = self._history.get(name, None) if ret is None: raise KeyError("No history metric available for {}!".format(name)) return ret
[docs] def histories(self): """ Returns: dict[name -> HistoryBuffer]: the HistoryBuffer for all scalars """ return self._history
[docs] def latest(self): """ Returns: dict[str -> (float, int)]: mapping from the name of each scalar to the most recent value and the iteration number its added. """ return self._latest_scalars
[docs] def latest_with_smoothing_hint(self, window_size=20): """ Similar to :meth:`latest`, but the returned values are either the un-smoothed original latest value, or a median of the given window_size, depending on whether the smoothing_hint is True. This provides a default behavior that other writers can use. """ result = {} for k, (v, itr) in self._latest_scalars.items(): result[k] = ( self._history[k].median(window_size) if self._smoothing_hints[k] else v, itr, ) return result
[docs] def smoothing_hints(self): """ Returns: dict[name -> bool]: the user-provided hint on whether the scalar is noisy and needs smoothing. """ return self._smoothing_hints
[docs] def step(self): """ User should either: (1) Call this function to increment storage.iter when needed. Or (2) Set `storage.iter` to the correct iteration number before each iteration. The storage will then be able to associate the new data with an iteration number. """ self._iter += 1
@property def iter(self): """ Returns the current iteration number. When used together with a trainer, this is ensured to be the same as trainer.iter. """ return self._iter @iter.setter def iter(self, val): self._iter = int(val) @property def samples(self): return self._samples @samples.setter def samples(self, val): self._samples = int(val) def __enter__(self): _CURRENT_STORAGE_STACK.append(self) return self def __exit__(self, exc_type, exc_val, exc_tb): assert _CURRENT_STORAGE_STACK[-1] == self _CURRENT_STORAGE_STACK.pop()
[docs] @contextmanager def name_scope(self, name): """ Yields: A context within which all the events added to this storage will be prefixed by the name scope. """ old_prefix = self._current_prefix self._current_prefix = name.rstrip("/") + "/" yield self._current_prefix = old_prefix
[docs] def clear_images(self): """ Delete all the stored images for visualization. This should be called after images are written to tensorboard. """ self._vis_data = []
[docs] def clear_histograms(self): """ Delete all the stored histograms for visualization. This should be called after histograms are written to tensorboard. """ self._histograms = []