Files
StarPilot/tinygrad_repo/examples/mlperf/lr_schedulers.py
T
firestar5683 22a8575199 Vendor dependencies and resources for standalone builds
Keep official openpilot ancestry and dependency licenses. Store resources directly in Git, remove LFS setup requirements, and leave the downloadable big model outside the source tree.
2026-10-03 21:01:18 +00:00

60 lines
3.0 KiB
Python

import math
from tinygrad import dtypes, Tensor
from tinygrad.nn.optim import Optimizer
from extra.lr_scheduler import LR_Scheduler
from typing import Callable
# https://github.com/mlcommons/training/blob/e237206991d10449d9675d95606459a3cb6c21ad/image_classification/tensorflow2/lars_util.py
class PolynomialDecayWithWarmup(LR_Scheduler):
def __init__(self, optimizer: Optimizer, initial_lr, end_lr, train_steps, warmup, power=2):
super().__init__(optimizer)
self.epoch_counter = self.epoch_counter.cast(dtypes.float32)
assert train_steps > 0 and warmup > 0
self.warmup = min(warmup, train_steps)
self.initial_lr, self.end_lr, self.epochs, self.power = initial_lr, end_lr, train_steps, power
# set lr for first warmup step
self.optimizer.lr.assign(self.get_lr()).realize()
def get_lr(self):
# LR is 0 on the first step, matching the reference.
warmup_lr = (self.epoch_counter * (1.0 / self.warmup)) * self.initial_lr
x = (1 - (self.epoch_counter - self.warmup) / (self.epochs - self.warmup + 1))
return (self.epoch_counter <= self.warmup).where(warmup_lr, (self.initial_lr - self.end_lr) * x ** self.power + self.end_lr).cast(self.optimizer.lr.dtype)
class CosineAnnealingLRWithWarmup(LR_Scheduler):
def __init__(self, optimizer:Optimizer, base_lr, end_lr, warmup_steps:int, decay_steps:int):
assert warmup_steps > 0 and decay_steps > 0
super().__init__(optimizer)
self.base_lr = base_lr
self.end_lr = end_lr
self.warmup_steps = warmup_steps
self.decay_steps = decay_steps
# set lr for first warmup step
self.optimizer.lr.assign(self.get_lr()).realize()
def get_lr(self):
warmup_lr = ((self.epoch_counter+1) / self.warmup_steps) * self.base_lr
decay_lr = self.end_lr + 0.5 * (self.base_lr-self.end_lr) * (1 + (((self.epoch_counter+1-self.warmup_steps)/self.decay_steps) * math.pi).cos())
return (self.epoch_counter < self.warmup_steps).where(warmup_lr, decay_lr).cast(self.optimizer.lr.dtype)
# Reference: https://github.com/mlcommons/training/blob/64b14a9abc74e08779a175abca7d291f8c957632/stable_diffusion/ldm/lr_scheduler.py, Lines 36-97
class LambdaLinearScheduler:
def __init__(self, warm_up_steps:int, f_min:float, f_max:float, f_start:float, cycle_lengths:int):
self.lr_warm_up_steps, self.f_min, self.f_max, self.f_start, self.cycle_lengths = warm_up_steps, f_min, f_max, f_start, cycle_lengths
def schedule(self, n:Tensor) -> Tensor:
warm_up = (n < self.lr_warm_up_steps)
f_warm_up = (self.f_max - self.f_start) / self.lr_warm_up_steps * n + self.f_start
return warm_up.where(f_warm_up, self.f_min + (self.f_max - self.f_min) * (self.cycle_lengths - n) / (self.cycle_lengths))
# based on torch.optim.lr_scheduler.LambdaLR
class LambdaLR(LR_Scheduler):
def __init__(self, optimizer:Optimizer, base_lr:Tensor, lr_lambda:Callable):
super().__init__(optimizer)
self.base_lr, self.lr_lambda = base_lr, lr_lambda
self.step()
def get_lr(self):
return self.base_lr * self.lr_lambda(self.epoch_counter - 1)