869 lines
35 KiB
Python
869 lines
35 KiB
Python
# Copyright 2022 Xiaomi Corp. (authors: Daniel Povey)
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#
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# See ../LICENSE for clarification regarding multiple authors
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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import contextlib
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import logging
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from collections import defaultdict
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from typing import Dict, List, Tuple
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import torch
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from lhotse.utils import fix_random_seed
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from torch import Tensor
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from torch.optim import Optimizer
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class BatchedOptimizer(Optimizer):
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"""
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This class adds to class Optimizer the capability to optimize parameters in batches:
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it will stack the parameters and their grads for you so the optimizer can work
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on tensors with an extra leading dimension. This is intended for speed with GPUs,
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as it reduces the number of kernels launched in the optimizer.
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Args:
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params:
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"""
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def __init__(self, params, defaults):
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super(BatchedOptimizer, self).__init__(params, defaults)
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@contextlib.contextmanager
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def batched_params(self, param_group, group_params_names):
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"""
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This function returns (technically, yields) a list of
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of tuples (p, state), where
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p is a `fake` parameter that is stacked (over axis 0) from real parameters
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that share the same shape, and its gradient is also stacked;
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`state` is the state corresponding to this batch of parameters
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(it will be physically located in the "state" for one of the real
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parameters, the last one that has any particular shape and dtype).
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This function is decorated as a context manager so that it can
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write parameters back to their "real" locations.
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The idea is, instead of doing:
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<code>
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for p in group["params"]:
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state = self.state[p]
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...
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</code>
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you can do:
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<code>
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with self.batched_params(group["params"]) as batches:
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for p, state, p_names in batches:
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...
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</code>
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Args:
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group: a parameter group, which is a list of parameters; should be
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one of self.param_groups.
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group_params_names: name for each parameter in group,
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which is List[str].
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"""
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batches = defaultdict(
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list
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) # `batches` maps from tuple (dtype_as_str,*shape) to list of nn.Parameter
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batches_names = defaultdict(
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list
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) # `batches` maps from tuple (dtype_as_str,*shape) to list of str
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assert len(param_group) == len(group_params_names)
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for p, named_p in zip(param_group, group_params_names):
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key = (str(p.dtype), *p.shape)
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batches[key].append(p)
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batches_names[key].append(named_p)
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batches_names_keys = list(batches_names.keys())
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sorted_idx = sorted(
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range(len(batches_names)), key=lambda i: batches_names_keys[i]
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)
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batches_names = [batches_names[batches_names_keys[idx]] for idx in sorted_idx]
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batches = [batches[batches_names_keys[idx]] for idx in sorted_idx]
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stacked_params_dict = dict()
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# turn batches into a list, in deterministic order.
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# tuples will contain tuples of (stacked_param, state, stacked_params_names),
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# one for each batch in `batches`.
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tuples = []
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for batch, batch_names in zip(batches, batches_names):
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p = batch[0]
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# we arbitrarily store the state in the
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# state corresponding to the 1st parameter in the
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# group. class Optimizer will take care of saving/loading state.
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state = self.state[p]
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p_stacked = torch.stack(batch)
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grad = torch.stack(
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[torch.zeros_like(p) if p.grad is None else p.grad for p in batch]
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)
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p_stacked.grad = grad
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stacked_params_dict[key] = p_stacked
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tuples.append((p_stacked, state, batch_names))
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yield tuples # <-- calling code will do the actual optimization here!
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for (stacked_params, _state, _names), batch in zip(tuples, batches):
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for i, p in enumerate(batch): # batch is list of Parameter
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p.copy_(stacked_params[i])
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def basic_step(group, p, state, grad):
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# computes basic Adam update using beta2 (dividing by gradient stddev) only. no
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# momentum yet.
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lr = group["lr"]
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if p.numel() == p.shape[0]:
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lr = lr * group["scalar_lr_scale"]
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beta2 = group["betas"][1]
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eps = group["eps"]
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# p shape: (batch_size,) or (batch_size, 1, [1,..])
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try:
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exp_avg_sq = state[
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"exp_avg_sq"
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] # shape: (batch_size,) or (batch_size, 1, [1,..])
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except KeyError:
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exp_avg_sq = torch.zeros(*p.shape, device=p.device, dtype=torch.float)
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state["exp_avg_sq"] = exp_avg_sq
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exp_avg_sq.mul_(beta2).addcmul_(grad, grad, value=1 - beta2)
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# bias_correction2 is like in Adam.
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# slower update at the start will help stability anyway.
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bias_correction2 = 1 - beta2 ** (state["step"] + 1)
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if bias_correction2 < 0.99:
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# note: not in-place.
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exp_avg_sq = exp_avg_sq * (1.0 / bias_correction2)
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denom = exp_avg_sq.sqrt().add_(eps)
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return -lr * grad / denom
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def scaling_step(group, p, state, grad):
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delta = basic_step(group, p, state, grad)
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if p.numel() == p.shape[0]:
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return delta
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# there is no scaling for scalar parameters.
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# (p.shape[0] is the batch of parameters.)
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step = state["step"]
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size_update_period = group["size_update_period"]
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try:
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param_rms = state["param_rms"]
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scale_grads = state["scale_grads"]
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scale_exp_avg_sq = state["scale_exp_avg_sq"]
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except KeyError:
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# we know p.ndim > 1 because we'd have returned above if not, so don't worry
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# about the speial case of dim=[] that pytorch treats inconsistently.
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param_rms = (p**2).mean(dim=list(range(1, p.ndim)), keepdim=True).sqrt()
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param_rms = param_rms.to(torch.float)
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scale_exp_avg_sq = torch.zeros_like(param_rms)
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scale_grads = torch.zeros(
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size_update_period,
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*param_rms.shape,
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dtype=torch.float,
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device=p.device,
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)
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state["param_rms"] = param_rms
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state["scale_grads"] = scale_grads
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state["scale_exp_avg_sq"] = scale_exp_avg_sq
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# on every step, update the gradient w.r.t. the scale of the parameter, we
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# store these as a batch and periodically update the size (for speed only, to
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# avoid too many operations).
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scale_grads[step % size_update_period] = (p * grad).sum(
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dim=list(range(1, p.ndim)), keepdim=True
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)
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# periodically recompute the value of param_rms.
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if step % size_update_period == size_update_period - 1:
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param_rms.copy_((p**2).mean(dim=list(range(1, p.ndim)), keepdim=True).sqrt())
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param_min_rms = group["param_min_rms"]
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# scale the step size by param_rms. This is the most important "scaling" part of
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# ScaledAdam
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delta *= param_rms.clamp(min=param_min_rms)
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if step % size_update_period == size_update_period - 1 and step > 0:
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# This block updates the size of parameter by adding a step ("delta") value in
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# the direction of either shrinking or growing it.
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beta2 = group["betas"][1]
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size_lr = group["lr"] * group["scalar_lr_scale"]
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param_max_rms = group["param_max_rms"]
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eps = group["eps"]
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# correct beta2 for the size update period: we will have
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# faster decay at this level.
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beta2_corr = beta2**size_update_period
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scale_exp_avg_sq.mul_(beta2_corr).add_(
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(scale_grads**2).mean(dim=0), # mean over dim `size_update_period`
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alpha=1 - beta2_corr,
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) # shape is (batch_size, 1, 1, ...)
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# The 1st time we reach here is when size_step == 1.
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size_step = (step + 1) // size_update_period
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bias_correction2 = 1 - beta2_corr**size_step
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denom = scale_exp_avg_sq.sqrt() + eps
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scale_step = (
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-size_lr * (bias_correction2**0.5) * scale_grads.sum(dim=0) / denom
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)
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is_too_small = param_rms < param_min_rms
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# when the param gets too small, just don't shrink it any further.
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scale_step.masked_fill_(is_too_small, 0.0)
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# The following may help prevent instability: don't allow the scale step to be
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# too large in either direction.
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scale_step.clamp_(min=-0.1, max=0.1)
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# and ensure the parameter rms after update never exceeds param_max_rms.
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# We have to look at the trained model for parameters at or around the
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# param_max_rms, because sometimes they can indicate a problem with the
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# topology or settings.
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scale_step = torch.minimum(scale_step, (param_max_rms - param_rms) / param_rms)
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delta.add_(p * scale_step)
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return delta
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def momentum_step(group, p, state, grad):
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delta = scaling_step(group, p, state, grad)
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beta1 = group["betas"][0]
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try:
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stored_delta = state["delta"]
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except KeyError:
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stored_delta = torch.zeros(*p.shape, device=p.device, dtype=torch.float)
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state["delta"] = stored_delta
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stored_delta.mul_(beta1)
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stored_delta.add_(delta, alpha=(1 - beta1))
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# we don't bother doing the "bias correction" part of Adam for beta1 because this is
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# just an edge effect that affects the first 10 or so batches; and the effect of not
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# doing it is just to do a slower update for the first few batches, which will help
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# stability.
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return stored_delta
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class ScaledAdam(BatchedOptimizer):
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"""
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Implements 'Scaled Adam', a variant of Adam where we scale each parameter's update
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proportional to the norm of that parameter; and also learn the scale of the
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parameter, in log space, subject to upper and lower limits (as if we had factored
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each parameter as param = underlying_param * log_scale.exp())
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Args:
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params: The parameters or param_groups to optimize (like other Optimizer
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subclasses) Unlike common optimizers, which accept
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model.parameters() or groups of parameters(), this optimizer
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could accept model.named_parameters() or groups of
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named_parameters(). See comments of function
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_get_names_of_parameters for its 4 possible cases.
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lr: The learning rate. We will typically use a learning rate schedule
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that starts at 0.03 and decreases over time, i.e. much higher
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than other common optimizers.
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clipping_scale: (e.g. 2.0)
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A scale for gradient-clipping: if specified, the normalized gradients
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over the whole model will be clipped to have 2-norm equal to
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`clipping_scale` times the median 2-norm over the most recent period
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of `clipping_update_period` minibatches. By "normalized gradients",
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we mean after multiplying by the rms parameter value for this tensor
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[for non-scalars]; this is appropriate because our update is scaled
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by this quantity.
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betas: beta1,beta2 are momentum constants for regular momentum, and moving
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sum-sq grad. Must satisfy 0 < beta <= beta2 < 1.
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scalar_lr_scale: A scaling factor on the learning rate, that we use to update the
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scale of each parameter tensor and scalar parameters of the mode..
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If each parameter were decomposed as p * p_scale.exp(),
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where (p**2).mean().sqrt() == 1.0, scalar_lr_scale would be a the
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scaling factor on the learning rate of p_scale.
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eps: A general-purpose epsilon to prevent division by zero
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param_min_rms: Minimum root-mean-square value of parameter tensor, for purposes of
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learning the scale on the parameters (we'll constrain the rms of
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each non-scalar parameter tensor to be >= this value)
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param_max_rms: Maximum root-mean-square value of parameter tensor, for purposes of
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learning the scale on the parameters (we'll constrain the rms of
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each non-scalar parameter tensor to be <= this value)
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scalar_max: Maximum absolute value for scalar parameters (applicable if your
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model has any parameters with numel() == 1).
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size_update_period: The periodicity, in steps, with which we update the size (scale)
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of the parameter tensor. This is provided to save a little time
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in the update.
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clipping_update_period: if clipping_scale is specified, this is the period
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"""
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def __init__(
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self,
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params,
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lr=3e-02,
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clipping_scale=None,
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betas=(0.9, 0.98),
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scalar_lr_scale=0.1,
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eps=1.0e-08,
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param_min_rms=1.0e-05,
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param_max_rms=3.0,
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scalar_max=10.0,
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size_update_period=4,
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clipping_update_period=100,
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):
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defaults = dict(
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lr=lr,
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clipping_scale=clipping_scale,
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betas=betas,
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scalar_lr_scale=scalar_lr_scale,
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eps=eps,
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param_min_rms=param_min_rms,
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param_max_rms=param_max_rms,
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scalar_max=scalar_max,
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size_update_period=size_update_period,
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clipping_update_period=clipping_update_period,
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)
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# If params only contains parameters or group of parameters,
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# i.e when parameter names are not given,
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# this flag will be set to False in funciton _get_names_of_parameters.
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self.show_dominant_parameters = True
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param_groups, parameters_names = self._get_names_of_parameters(params)
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super(ScaledAdam, self).__init__(param_groups, defaults)
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assert len(self.param_groups) == len(parameters_names)
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self.parameters_names = parameters_names
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def _get_names_of_parameters(
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self, params_or_named_params
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) -> Tuple[List[Dict], List[List[str]]]:
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"""
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Args:
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params_or_named_params: according to the way ScaledAdam is initialized
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in train.py, this argument could be one of following 4 cases,
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case 1, a generator of parameter, e.g.:
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optimizer = ScaledAdam(model.parameters(), lr=params.base_lr,
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clipping_scale=3.0)
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case 2, a list of parameter groups with different config, e.g.:
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model_param_groups = [
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{'params': model.encoder.parameters(), 'lr': 0.05},
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{'params': model.decoder.parameters(), 'lr': 0.01},
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{'params': model.joiner.parameters(), 'lr': 0.03},
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]
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optimizer = ScaledAdam(model_param_groups, lr=params.base_lr,
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clipping_scale=3.0)
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case 3, a generator of named_parameter, e.g.:
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optimizer = ScaledAdam(model.named_parameters(), lr=params.base_lr,
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clipping_scale=3.0)
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case 4, a list of named_parameter groups with different config, e.g.:
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model_named_param_groups = [
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{'named_params': model.encoder.named_parameters(), 'lr': 0.05},
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{'named_params': model.decoder.named_parameters(), 'lr': 0.01},
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{'named_params': model.joiner.named_parameters(), 'lr': 0.03},
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]
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optimizer = ScaledAdam(model_named_param_groups, lr=params.base_lr,
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clipping_scale=3.0)
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For case 1 and case 2, input params is used to initialize the underlying
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torch.optimizer.
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For case 3 and case 4, firstly, names and params are extracted from input
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named_params, then, these extracted params are used to initialize the
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underlying torch.optimizer, and these extracted names are mainly used by
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function `_show_gradient_dominating_parameter`
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Returns:
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Returns a tuple containing 2 elements:
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- `param_groups` with type List[Dict], each Dict element is a parameter
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group. An example of `param_groups` could be:
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[
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{'params': `one iterable of Parameter`, 'lr': 0.05},
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{'params': `another iterable of Parameter`, 'lr': 0.08},
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{'params': `a third iterable of Parameter`, 'lr': 0.1},
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]
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- `param_gruops_names` with type List[List[str]],
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each `List[str]` is for a group['params'] in param_groups,
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and each `str` is the name of a parameter.
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A dummy name "foo" is related to each parameter,
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if input are params without names, i.e. case 1 or case 2.
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"""
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# variable naming convention in this function:
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# p is short for param.
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# np is short for named_param.
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# p_or_np is short for param_or_named_param.
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# cur is short for current.
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# group is a dict,
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# e.g. {'params': iterable of parameter, 'lr': 0.05, other fields}.
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# groups is a List[group]
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iterable_or_groups = list(params_or_named_params)
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if len(iterable_or_groups) == 0:
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raise ValueError("optimizer got an empty parameter list")
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# The first value of returned tuple. A list of dicts containing at
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# least 'params' as a key.
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param_groups = []
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# The second value of returned tuple,
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# a List[List[str]], each sub-List is for a group.
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param_groups_names = []
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if not isinstance(iterable_or_groups[0], dict):
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# case 1 or case 3,
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# the input is an iterable of parameter or named parameter.
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param_iterable_cur_group = []
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param_names_cur_group = []
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for p_or_np in iterable_or_groups:
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if isinstance(p_or_np, tuple):
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# case 3
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name, param = p_or_np
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else:
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# case 1
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assert isinstance(p_or_np, torch.Tensor)
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param = p_or_np
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# Assign a dummy name as a placeholder
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name = "foo"
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self.show_dominant_parameters = False
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param_iterable_cur_group.append(param)
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param_names_cur_group.append(name)
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param_groups.append({"params": param_iterable_cur_group})
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param_groups_names.append(param_names_cur_group)
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else:
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# case 2 or case 4
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# the input is groups of parameter or named parameter.
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for cur_group in iterable_or_groups:
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if "named_params" in cur_group:
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name_list = [x[0] for x in cur_group["named_params"]]
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p_list = [x[1] for x in cur_group["named_params"]]
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del cur_group["named_params"]
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cur_group["params"] = p_list
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else:
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assert "params" in cur_group
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name_list = ["foo" for _ in cur_group["params"]]
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param_groups.append(cur_group)
|
|
param_groups_names.append(name_list)
|
|
|
|
return param_groups, param_groups_names
|
|
|
|
def __setstate__(self, state):
|
|
super(ScaledAdam, self).__setstate__(state)
|
|
|
|
@torch.no_grad()
|
|
def step(self, closure=None):
|
|
"""Performs a single optimization step.
|
|
|
|
Arguments:
|
|
closure (callable, optional): A closure that reevaluates the model
|
|
and returns the loss.
|
|
"""
|
|
loss = None
|
|
if closure is not None:
|
|
with torch.enable_grad():
|
|
loss = closure()
|
|
|
|
for group, group_params_names in zip(self.param_groups, self.parameters_names):
|
|
|
|
with self.batched_params(group["params"], group_params_names) as batches:
|
|
|
|
# batches is list of pairs (stacked_param, state). stacked_param is
|
|
# like a regular parameter, and will have a .grad, but the 1st dim
|
|
# corresponds to a stacking dim, it is not a real dim.
|
|
|
|
if (
|
|
len(batches[0][1]) == 0
|
|
): # if len(first state) == 0: not yet initialized
|
|
clipping_scale = 1
|
|
else:
|
|
clipping_scale = self._get_clipping_scale(group, batches)
|
|
|
|
for p, state, _ in batches:
|
|
# Perform optimization step.
|
|
# grad is not going to be None, we handled that when creating the
|
|
# batches.
|
|
grad = p.grad
|
|
if grad.is_sparse:
|
|
raise RuntimeError(
|
|
"ScaledAdam optimizer does not support sparse gradients"
|
|
)
|
|
|
|
try:
|
|
cur_step = state["step"]
|
|
except KeyError:
|
|
state["step"] = 0
|
|
cur_step = 0
|
|
|
|
grad = (
|
|
p.grad if clipping_scale == 1.0 else p.grad.mul_(clipping_scale)
|
|
)
|
|
p += momentum_step(group, p.detach(), state, grad)
|
|
|
|
if p.numel() == p.shape[0]: # scalar parameter
|
|
scalar_max = group["scalar_max"]
|
|
p.clamp_(min=-scalar_max, max=scalar_max)
|
|
|
|
state["step"] = cur_step + 1
|
|
|
|
return loss
|
|
|
|
def _get_clipping_scale(
|
|
self, group: dict, tuples: List[Tuple[Tensor, dict, List[str]]]
|
|
) -> float:
|
|
"""
|
|
Returns a scalar factor <= 1.0 that dictates gradient clipping, i.e. we will
|
|
scale the gradients by this amount before applying the rest of the update.
|
|
|
|
Args:
|
|
group: the parameter group, an item in self.param_groups
|
|
tuples: a list of tuples of (param, state, param_names)
|
|
where param is a batched set of parameters,
|
|
with a .grad (1st dim is batch dim)
|
|
and state is the state-dict where optimization parameters are kept.
|
|
param_names is a List[str] while each str is name for a parameter
|
|
in batched set of parameters "param".
|
|
"""
|
|
assert len(tuples) >= 1
|
|
clipping_scale = group["clipping_scale"]
|
|
(first_p, first_state, _) = tuples[0]
|
|
step = first_state["step"]
|
|
if clipping_scale is None or step == 0:
|
|
# no clipping. return early on step == 0 because the other
|
|
# parameters' state won't have been initialized yet.
|
|
return 1.0
|
|
clipping_update_period = group["clipping_update_period"]
|
|
scalar_lr_scale = group["scalar_lr_scale"]
|
|
|
|
tot_sumsq = torch.tensor(0.0, device=first_p.device)
|
|
for p, state, param_names in tuples:
|
|
grad = p.grad
|
|
if grad.is_sparse:
|
|
raise RuntimeError(
|
|
"ScaledAdam optimizer does not support sparse gradients"
|
|
)
|
|
if p.numel() == p.shape[0]: # a batch of scalars
|
|
tot_sumsq += (grad**2).sum() * (
|
|
scalar_lr_scale**2
|
|
) # sum() to change shape [1] to []
|
|
else:
|
|
tot_sumsq += ((grad * state["param_rms"]) ** 2).sum()
|
|
|
|
tot_norm = tot_sumsq.sqrt()
|
|
if "model_norms" not in first_state:
|
|
first_state["model_norms"] = torch.zeros(
|
|
clipping_update_period, device=p.device
|
|
)
|
|
first_state["model_norms"][step % clipping_update_period] = tot_norm
|
|
|
|
irregular_estimate_steps = [
|
|
i for i in [10, 20, 40] if i < clipping_update_period
|
|
]
|
|
if step % clipping_update_period == 0 or step in irregular_estimate_steps:
|
|
# Print some stats.
|
|
# We don't reach here if step == 0 because we would have returned
|
|
# above.
|
|
sorted_norms = first_state["model_norms"].sort()[0].to("cpu")
|
|
if step in irregular_estimate_steps:
|
|
sorted_norms = sorted_norms[-step:]
|
|
num_norms = sorted_norms.numel()
|
|
quartiles = []
|
|
for n in range(0, 5):
|
|
index = min(num_norms - 1, (num_norms // 4) * n)
|
|
quartiles.append(sorted_norms[index].item())
|
|
|
|
median = quartiles[2]
|
|
if median - median != 0:
|
|
raise RuntimeError("Too many grads were not finite")
|
|
threshold = clipping_scale * median
|
|
if step in irregular_estimate_steps:
|
|
# use larger thresholds on first few steps of estimating threshold,
|
|
# as norm may be changing rapidly.
|
|
threshold = threshold * 2.0
|
|
first_state["model_norm_threshold"] = threshold
|
|
percent_clipped = (
|
|
first_state["num_clipped"] * 100.0 / num_norms
|
|
if "num_clipped" in first_state
|
|
else 0.0
|
|
)
|
|
first_state["num_clipped"] = 0
|
|
quartiles = " ".join(["%.3e" % x for x in quartiles])
|
|
logging.warning(
|
|
f"Clipping_scale={clipping_scale}, grad-norm quartiles {quartiles}, "
|
|
f"threshold={threshold:.3e}, percent-clipped={percent_clipped:.1f}"
|
|
)
|
|
|
|
try:
|
|
model_norm_threshold = first_state["model_norm_threshold"]
|
|
except KeyError:
|
|
return 1.0 # threshold has not yet been set.
|
|
|
|
ans = min(1.0, (model_norm_threshold / (tot_norm + 1.0e-20)).item())
|
|
if ans != ans: # e.g. ans is nan
|
|
ans = 0.0
|
|
if ans < 1.0:
|
|
first_state["num_clipped"] += 1
|
|
if ans < 0.5:
|
|
logging.debug(
|
|
f"Scaling gradients by {ans}, "
|
|
f"model_norm_threshold={model_norm_threshold}"
|
|
)
|
|
if self.show_dominant_parameters:
|
|
assert p.shape[0] == len(param_names)
|
|
self._show_gradient_dominating_parameter(
|
|
tuples, tot_sumsq, group["scalar_lr_scale"]
|
|
)
|
|
self._show_param_with_unusual_grad(tuples)
|
|
|
|
if ans == 0.0:
|
|
for p, state, param_names in tuples:
|
|
p.grad.zero_() # get rid of infinity()
|
|
|
|
return ans
|
|
|
|
def _show_param_with_unusual_grad(
|
|
self,
|
|
tuples: List[Tuple[Tensor, dict, List[str]]],
|
|
):
|
|
"""
|
|
Print information about parameter which has the largest ratio of
|
|
grad-on-this-batch divided by normal grad size.
|
|
tuples: a list of tuples of (param, state, param_names)
|
|
where param is a batched set of parameters,
|
|
with a .grad (1st dim is batch dim)
|
|
and state is the state-dict where optimization parameters are kept.
|
|
param_names is a List[str] while each str is name for a parameter
|
|
in batched set of parameters "param".
|
|
"""
|
|
# ratios_names is a list of 3-tuples: (grad_ratio, param_name, tensor)
|
|
ratios_names = []
|
|
for p, state, batch_param_names in tuples:
|
|
dims = list(range(1, p.ndim))
|
|
|
|
def mean(x):
|
|
# workaround for bad interface of torch's "mean" for when dims is the
|
|
# empty list.
|
|
if len(dims) > 0:
|
|
return x.mean(dim=dims)
|
|
else:
|
|
return x
|
|
|
|
grad_ratio = (
|
|
(mean(p.grad**2) / state["exp_avg_sq"].mean(dim=dims))
|
|
.sqrt()
|
|
.to("cpu")
|
|
)
|
|
|
|
ratios_names += zip(
|
|
grad_ratio.tolist(), batch_param_names, p.grad.unbind(dim=0)
|
|
)
|
|
|
|
ratios_names = sorted(ratios_names, reverse=True)
|
|
ratios_names = ratios_names[:10]
|
|
ratios_names = [
|
|
(ratio, name, largest_index(tensor))
|
|
for (ratio, name, tensor) in ratios_names
|
|
]
|
|
|
|
logging.debug(
|
|
f"Parameters with most larger-than-usual grads, with ratios, "
|
|
f"are: {ratios_names}"
|
|
)
|
|
|
|
def _show_gradient_dominating_parameter(
|
|
self,
|
|
tuples: List[Tuple[Tensor, dict, List[str]]],
|
|
tot_sumsq: Tensor,
|
|
scalar_lr_scale: float,
|
|
):
|
|
"""
|
|
Show information of parameter which dominates tot_sumsq.
|
|
|
|
Args:
|
|
tuples: a list of tuples of (param, state, param_names)
|
|
where param is a batched set of parameters,
|
|
with a .grad (1st dim is batch dim)
|
|
and state is the state-dict where optimization parameters are kept.
|
|
param_names is a List[str] while each str is name for a parameter
|
|
in batched set of parameters "param".
|
|
tot_sumsq: sumsq of all parameters. Though it's could be calculated
|
|
from tuples, we still pass it to save some time.
|
|
"""
|
|
all_sumsq_orig = {}
|
|
for p, state, batch_param_names in tuples:
|
|
# p is a stacked batch parameters.
|
|
batch_grad = p.grad
|
|
if p.numel() == p.shape[0]: # a batch of scalars
|
|
# Dummy values used by following `zip` statement.
|
|
batch_rms_orig = torch.full(
|
|
p.shape, scalar_lr_scale, device=batch_grad.device
|
|
)
|
|
else:
|
|
batch_rms_orig = state["param_rms"]
|
|
batch_sumsq_orig = (batch_grad * batch_rms_orig) ** 2
|
|
if batch_grad.ndim > 1:
|
|
# need to guard it with if-statement because sum() sums over
|
|
# all dims if dim == ().
|
|
batch_sumsq_orig = batch_sumsq_orig.sum(
|
|
dim=list(range(1, batch_grad.ndim))
|
|
)
|
|
for name, sumsq_orig, rms, grad in zip(
|
|
batch_param_names, batch_sumsq_orig, batch_rms_orig, batch_grad
|
|
):
|
|
|
|
proportion_orig = sumsq_orig / tot_sumsq
|
|
all_sumsq_orig[name] = (proportion_orig, sumsq_orig, rms, grad)
|
|
|
|
sorted_by_proportion = {
|
|
k: v
|
|
for k, v in sorted(
|
|
all_sumsq_orig.items(),
|
|
key=lambda item: item[1][0],
|
|
reverse=True,
|
|
)
|
|
}
|
|
dominant_param_name = next(iter(sorted_by_proportion))
|
|
(
|
|
dominant_proportion,
|
|
dominant_sumsq,
|
|
dominant_rms,
|
|
dominant_grad,
|
|
) = sorted_by_proportion[dominant_param_name]
|
|
logging.debug(
|
|
f"Parameter dominating tot_sumsq {dominant_param_name}"
|
|
f" with proportion {dominant_proportion:.2f},"
|
|
f" where dominant_sumsq=(grad_sumsq*orig_rms_sq)"
|
|
f"={dominant_sumsq:.3e},"
|
|
f" grad_sumsq={(dominant_grad**2).sum():.3e},"
|
|
f" orig_rms_sq={(dominant_rms**2).item():.3e}"
|
|
)
|
|
|
|
|
|
def largest_index(x: Tensor):
|
|
x = x.contiguous()
|
|
argmax = x.abs().argmax().item()
|
|
return [(argmax // x.stride(i)) % x.size(i) for i in range(x.ndim)]
|
|
|
|
|
|
def _test_scaled_adam(hidden_dim: int):
|
|
import timeit
|
|
|
|
from zipvoice.models.modules.scaling import ScaledLinear
|
|
from zipvoice.utils.lr_scheduler import Eden
|
|
|
|
E = 100
|
|
B = 4
|
|
T = 2
|
|
logging.info("in test_eve_cain")
|
|
# device = torch.device('cuda')
|
|
device = torch.device("cpu")
|
|
dtype = torch.float32
|
|
|
|
fix_random_seed(42)
|
|
# these input_magnitudes and output_magnitudes are to test that
|
|
# Abel is working as we expect and is able to adjust scales of
|
|
# different dims differently.
|
|
input_magnitudes = (1.0 * torch.randn(E, dtype=dtype, device=device)).exp()
|
|
output_magnitudes = (1.0 * torch.randn(E, dtype=dtype, device=device)).exp()
|
|
|
|
fix_random_seed(42)
|
|
Linear = ScaledLinear
|
|
|
|
m = torch.nn.Sequential(
|
|
Linear(E, hidden_dim),
|
|
torch.nn.PReLU(),
|
|
Linear(hidden_dim, hidden_dim),
|
|
torch.nn.PReLU(),
|
|
Linear(hidden_dim, E),
|
|
).to(device)
|
|
|
|
train_pairs = [
|
|
(
|
|
100.0 * torch.randn(B, T, E, device=device, dtype=dtype) * input_magnitudes,
|
|
torch.randn(B, T, E, device=device, dtype=dtype) * output_magnitudes,
|
|
)
|
|
for _ in range(20)
|
|
]
|
|
optim = ScaledAdam(m.named_parameters(), lr=0.03, clipping_scale=2.0)
|
|
scheduler = Eden(optim, lr_batches=200, lr_epochs=5, verbose=False)
|
|
|
|
start = timeit.default_timer()
|
|
avg_loss = 0.0
|
|
for epoch in range(180):
|
|
scheduler.step_epoch()
|
|
# if epoch == 100 and iter in [2,3]:
|
|
# optim.reset_speedup() # check it doesn't crash.
|
|
|
|
# if epoch == 130:
|
|
# opts = diagnostics.TensorDiagnosticOptions(
|
|
# 512
|
|
# ) # allow 4 megabytes per sub-module
|
|
# diagnostic = diagnostics.attach_diagnostics(m, opts)
|
|
|
|
for n, (x, y) in enumerate(train_pairs):
|
|
y_out = m(x)
|
|
loss = ((y_out - y) ** 2).mean() * 100.0
|
|
if epoch == 0 and n == 0:
|
|
avg_loss = loss.item()
|
|
else:
|
|
avg_loss = 0.98 * avg_loss + 0.02 * loss.item()
|
|
if n == 0 and epoch % 5 == 0:
|
|
# norm1 = '%.2e' % (m[0].weight**2).mean().sqrt().item()
|
|
# norm1b = '%.2e' % (m[0].bias**2).mean().sqrt().item()
|
|
# norm2 = '%.2e' % (m[2].weight**2).mean().sqrt().item()
|
|
# norm2b = '%.2e' % (m[2].bias**2).mean().sqrt().item()
|
|
# scale1 = '%.2e' % (m[0].weight_scale.exp().item())
|
|
# scale1b = '%.2e' % (m[0].bias_scale.exp().item())
|
|
# scale2 = '%.2e' % (m[2].weight_scale.exp().item())
|
|
# scale2b = '%.2e' % (m[2].bias_scale.exp().item())
|
|
lr = scheduler.get_last_lr()[0]
|
|
logging.info(
|
|
f"Iter {iter}, epoch {epoch}, batch {n}, "
|
|
f"avg_loss {avg_loss:.4g}, lr={lr:.4e}"
|
|
) # , norms={norm1,norm1b,norm2,norm2b}")
|
|
# scales={scale1,scale1b,scale2,scale2b}
|
|
loss.log().backward()
|
|
optim.step()
|
|
optim.zero_grad()
|
|
scheduler.step_batch()
|
|
|
|
# diagnostic.print_diagnostics()
|
|
|
|
stop = timeit.default_timer()
|
|
logging.info(f"Iter={iter}, Time taken: {stop - start}")
|
|
|
|
logging.info(f"last lr = {scheduler.get_last_lr()}")
|
|
# logging.info("state dict = ", scheduler.state_dict())
|
|
# logging.info("optim state_dict = ", optim.state_dict())
|
|
logging.info(f"input_magnitudes = {input_magnitudes}")
|
|
logging.info(f"output_magnitudes = {output_magnitudes}")
|
|
|
|
|
|
if __name__ == "__main__":
|
|
torch.set_num_threads(1)
|
|
torch.set_num_interop_threads(1)
|
|
logging.getLogger().setLevel(logging.INFO)
|
|
import subprocess
|
|
|
|
s = subprocess.check_output(
|
|
"git status -uno .; git log -1; git diff HEAD .", shell=True
|
|
)
|
|
logging.info(s)
|
|
import sys
|
|
|
|
if len(sys.argv) > 1:
|
|
hidden_dim = int(sys.argv[1])
|
|
else:
|
|
hidden_dim = 200
|
|
|
|
_test_scaled_adam(hidden_dim)
|