| # Licensed to the Apache Software Foundation (ASF) under one |
| # or more contributor license agreements. See the NOTICE file |
| # distributed with this work for additional information |
| # regarding copyright ownership. The ASF licenses this file |
| # to you 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 copy |
| import numpy as np |
| from collections import OrderedDict |
| from neural_compressor.strategy.strategy import TuneStrategy, strategy_registry |
| |
| plot_operator_influence = False |
| |
| def calc_approx_error(expected_tensor: np.ndarray, observed_tensor: np.ndarray) -> float: |
| ''' |
| Calculating relative error for one tensor |
| ''' |
| error = observed_tensor - expected_tensor |
| absolute_error = np.abs(error) |
| mean_absolute_error = absolute_error.mean() |
| mean_expected_value = np.abs(expected_tensor).mean() |
| error = mean_absolute_error / mean_expected_value |
| return error |
| |
| |
| def get_approx_errors(expected_tensors, observed_tensors): |
| ''' |
| Calculating relative error for multiple tensors: Dict[tensors_name: str, tensor: np.ndarray] |
| ''' |
| errors = {} |
| for node_name in observed_tensors.keys(): |
| expected_tensor = expected_tensors[node_name][node_name] |
| observed_tensor = observed_tensors[node_name][node_name] |
| errors[node_name] = calc_approx_error(expected_tensor, observed_tensor) |
| return errors |
| |
| |
| @strategy_registry |
| class MyCustomTuneStrategy(TuneStrategy): |
| '''INC Custom strategy definition''' |
| def __init__(self, model, conf, q_dataloader, q_func=None, |
| eval_dataloader=None, eval_func=None, dicts=None, q_hooks=None): |
| super().__init__( |
| model, |
| conf, |
| q_dataloader, |
| q_func, |
| eval_dataloader, |
| eval_func, |
| dicts, |
| q_hooks) |
| |
| |
| def get_qtensors(self, quant_cfg, node_list): |
| ''' |
| Generating quantized model based on configuration and capturing intermediate tensors |
| ''' |
| qmodel = self.adaptor.quantize(quant_cfg, self.model, self.calib_dataloader) |
| tensors = self.adaptor.inspect_tensor(qmodel, self.calib_dataloader, node_list, [1]) # 1 is a batch index |
| return tensors['activation'][0] # we need to specify that we want activation (layer output) because INC stores also weight tensors |
| # 0 is the first batch |
| def next_tune_cfg(self): |
| FALLBACK_DTYPE = 'fp32' |
| |
| # creating base configuration - all nodes are quantized and calibrated with minmax algorithm |
| best_cfg = {} |
| best_cfg['calib_iteration'] = int(self.calib_iter[0]) # number of batches for calibration |
| best_cfg['calib_sampling_size'] = int(self.calib_sampling_size[0]) # number of samples for calibration (multiplicity of batch) |
| nodes_cfg = OrderedDict() |
| nodes_cfg_idx = {} |
| for node_key, cfgs in self.opwise_tune_cfgs.items(): |
| for i, cfg in enumerate(cfgs): |
| if cfg['activation']['algorithm'] == 'minmax': |
| nodes_cfg_idx[node_key] = i |
| break |
| nodes_cfg[node_key] = cfg |
| best_cfg['op'] = nodes_cfg |
| |
| yield best_cfg |
| |
| # If fully quantized model does not meet the requirements, we proceed to exclude some nodes |
| |
| # Collecting tensors from the original model - expected tensors |
| node_list = [op_name for (op_name, op_type) in best_cfg['op'].keys()] |
| f32_tensors = self.adaptor.inspect_tensor(self.model, self.calib_dataloader, node_list, [1]) |
| f32_tensors = f32_tensors['activation'][0] |
| |
| # Collecting tensors from the fully quantized model |
| q_tensors = self.get_qtensors(best_cfg, node_list) |
| approx_errors = get_approx_errors(f32_tensors, q_tensors) |
| |
| # best_cfg['op'] is an OrderedDict, which order of elements should correspond to their |
| # order in the computational graph |
| for node_key, cfg in best_cfg['op'].items(): |
| # Node's key in INC is its name + its operator |
| node_name, node_op = node_key |
| # Checking what configuration options are available for this particular node |
| capabilities = self.opwise_tune_space[node_key]['activation']['dtype'] |
| # If a particular node can be excluded from quanrtization ('fp32' in capabilities) |
| # and current error is bigger than threshold value, we check what accuracy improvement |
| # would be achieved by this exclusion |
| if FALLBACK_DTYPE in capabilities and approx_errors[node_name] > 0.06: |
| original_dtype = cfg['activation']['dtype'] |
| cfg['activation']['dtype'] = FALLBACK_DTYPE # Exclude the node from quantization |
| |
| # Collecting tensors for a new configuration with the current node excluded |
| q_tensors = self.get_qtensors(best_cfg, node_list) |
| # Calculating errors for the new configuration |
| new_approx_errors = get_approx_errors(f32_tensors, q_tensors) |
| # Calculating error differences for every node in a model |
| err_diffs = {} |
| for tensor_node_name in new_approx_errors.keys(): |
| diff = approx_errors[tensor_node_name] - new_approx_errors[tensor_node_name] |
| err_diffs[tensor_node_name] = diff |
| err_diffs_arr = np.array(list(err_diffs.values())) |
| |
| # If the sum of errors on the following layers is greater than the threshold value we |
| # keep the node excluded |
| threshold_sum_error_layers = err_diffs_arr.size * 0.007 |
| if err_diffs_arr.sum() >= threshold_sum_error_layers: |
| before = approx_errors |
| after = approx_errors.copy() |
| after.update(new_approx_errors) |
| if plot_operator_influence: |
| import matplotlib.pyplot as plt |
| plt.figure() |
| plt.plot(before.values(), marker='o', markersize=2.5, label='Before') |
| plt.plot(after.values(), marker='o', markersize=2.5, label='After') |
| plt.ylabel('Relative error') |
| plt.xlabel('Layer') |
| plt.legend() |
| plt.savefig(f'{node_name}_error.png') |
| |
| approx_errors.update(new_approx_errors) |
| nodes_cfg_idx.pop(node_key) # Mark node as not quantizable |
| else: |
| cfg['activation']['dtype'] = original_dtype |
| |
| yield best_cfg |
| |
| # Choosing calibration algorithm (kl or minmax) for every node which was not excluded from quantization |
| for cfg in self.bayesian_configurations(best_cfg, nodes_cfg_idx): |
| yield cfg |
| |
| def bayesian_params_to_tune_configs(self, params): |
| ''' |
| Creating configuration from params - changing configurations' indexes for real configurations |
| ''' |
| node_cfgs = {} |
| for node_key, configs in self.opwise_quant_cfgs.items(): |
| if node_key in params: |
| value = int(params[node_key]) |
| value = min(value, len(configs) - 1) |
| node_cfgs[node_key] = copy.deepcopy(configs[value]) |
| return node_cfgs |
| |
| def bayesian_configurations(self, cfg_base, params_base): |
| from neural_compressor.strategy.bayesian import BayesianOptimization |
| |
| # For each node we specify the possible range of values (we treat them as a configurations' index) |
| pbounds = {} |
| for node_key, configs in self.opwise_quant_cfgs.items(): |
| if node_key in params_base and len(configs) > 1: |
| pbounds[node_key] = (0, len(configs)) |
| |
| cfg = copy.deepcopy(cfg_base) |
| if len(pbounds) == 0: # if there is nothing to be optimized, we finish |
| cfg['op'].update(self.bayesian_params_to_tune_configs(params_base)) |
| return |
| |
| bayes_opt = BayesianOptimization(pbounds=pbounds, random_seed=self.cfg.tuning.random_seed) |
| bayes_opt._space.register(params_base, self.last_tune_result[0]) # registering the outcome of current configuration |
| while True: |
| # Generating next configuration |
| params = bayes_opt.gen_next_params() |
| cfg['op'].update(self.bayesian_params_to_tune_configs(params)) |
| yield cfg |
| try: |
| # Registering the outcome |
| bayes_opt._space.register(params, self.last_tune_result[0]) |
| except KeyError: |
| pass |