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torch_scheduler.py
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653 lines (560 loc) · 28.6 KB
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from __future__ import absolute_import
import os
import threading
import logging
import time
try:
import queue
except ImportError:
import Queue as queue
import torch
from bytecore_custom import core
from torch_task import TorchTask, BYTESCHEDULER_LIB
from torch.nn.parameter import Parameter
import time
import math
import torch.distributed as dist
import csv
from fairscale.utils.parallel import (
chunk_and_pad,
enable_pytorch_sync_bn,
get_process_group_cached,
validate_process_group,
)
#logging.basicConfig(level=logging.DEBUG)
class ShardScheduler(torch.optim.Optimizer):
"""An optimizer that wraps a hvd._DistributedOptimizer, intercepting allreduce operations and wrap as tasks."""
def __init__(self, model, named_parameters, size, rank, opt,
partition_threshold, done_counts, partition_counts,
rs_locks, ag_locks, ag_fsdp_locks,
rs_conditions, ag_conditions, ag_fsdp_conditions,
forward_conditions, backward_conditions,
lazy_init_locks, lazy_init_conditions,
num_steps=10**6, comm_stream=None, schedules=None):
"""Construct a new ScheduledOptimizer, which uses horovod optimizer under the hood for averaging gradients
across all the Horovod ranks.
Args:
model: The training model. ByteScheduler uses the model object to register hooks.
hvd_opt: Optimizer to use for averaging gradients and applying updates.
num_steps: The maximum number of training steps. ByteScheduler needs to know when to stop cross-iteration
scheduling.
Usage example:
```
import bytescheduler.pytorch.horovod as bsc
bsc.init()
optimizer = hvd.DistributedOptimizer(optimizer, named_parameters, compression)
optimizer = bsc.ScheduledOptimizer(model, optimizer, num_steps)
```
"""
print("!!!!!!!!!!!!!!!!!!!!")
#handle = BYTESCHEDULER_LIB.bytescheduler_create_event(0)
#super(self.__class__, self).__init__(model.parameters())
self._model = model
self._size= size
self._rank = rank
self._opt = opt
self._logger = logging.getLogger("ByteScheduler")
self._logger.debug("hvd size {}, rank {}".format(size, rank))
self._desc = "rank {}".format(rank)
self._grad_accs = []
self._requires_update = set()
self._handles = {}
#self._handlequeue = queue.Queue()
self._handlequeue = []
# Track training steps
self._step = 0
self._final_step = num_steps
self.partition_threshold = partition_threshold
self.done_counts = done_counts
self.partition_counts = partition_counts
self._rs_locks = rs_locks
self._ag_locks = ag_locks
self._ag_fsdp_locks = ag_fsdp_locks
self._rs_conditions = rs_conditions
self._ag_conditions = ag_conditions
self._ag_fsdp_conditions = ag_fsdp_conditions
self._forward_conditions = forward_conditions
self._backward_conditions = backward_conditions
self._lazy_init_locks = lazy_init_locks
self._lazy_init_conditions = lazy_init_conditions
self.comm_stream = comm_stream
if named_parameters is not None:
named_parameters = list(named_parameters)
else:
named_parameters = [(f'allreduce.noname.{i}.{j}', v)
for i, param_group in enumerate(self.param_groups)
for j, v in enumerate(param_group['params'])]
# make sure that named_parameters are tuples
if any([not isinstance(p, tuple) for p in named_parameters]):
raise ValueError('named_parameters should be a sequence of '
'tuples (name, parameter), usually produced by '
'model.named_parameters().')
dups = ShardScheduler.find_duplicates([k for k, _ in named_parameters])
if len(dups) > 0:
raise ValueError('Parameter names in named_parameters must be unique. '
'Found duplicates: %s' % ', '.join(dups))
all_param_ids = {id(v)
for param_group in self.param_groups
for v in param_group['params']}
named_param_ids = {id(v) for k, v in named_parameters}
unnamed_param_ids = all_param_ids - named_param_ids
if len(unnamed_param_ids):
raise ValueError('named_parameters was specified, but one or more model '
'parameters were not named. Python object ids: '
'%s' % ', '.join(str(id) for id in unnamed_param_ids))
backward_passes_per_step=1
self._parameter_names = {v: k for k, v in sorted(named_parameters)}
self.backward_passes_per_step = backward_passes_per_step
self._allreduce_delay = {v: self.backward_passes_per_step
for _, v in sorted(named_parameters)}
# Use lock to block the forward propagation of each parameter.
self.schedules = schedules
self.is_first_itr = True
# The closer to input layer, the higher the priority is.
self._priority_indexes = {}
priority = 0
for p in model.parameters():
self._priority_indexes[p] = priority
priority += 1
# Poll whether the tensor is ready for allreduce or whether the allreduce is finished.
self.event_queue = queue.Queue()
self.all_reduce_stream = torch.cuda.Stream()
self._poller = threading.Thread(target=self._poll_FSDP, args=())
self._poller.start()
# Let rank 0 decide the communication order.
self._immediate = False
#if self._rank != 0:
# self._immediate = True
#core.start(self._parameter_names, rank=self._rank, arch="allreduce")
#def start_scheduler(self):
@staticmethod
def find_duplicates(lst):
seen = set()
dups = set()
for el in lst:
if el in seen:
dups.add(el)
seen.add(el)
return dups
def __getattr__(self, item):
return getattr(self._opt, item)
def __del__(self):
"""Clean up"""
self.event_queue.put((None, None, None, None, None))
self._poller.join()
#core.shutdown(wait_for_all=False)
def step(self, closure=None):
"""Override the default step function."""
self._logger.debug("{} calls step() {}".format(self._desc, self._step))
#for i in range(self._handlequeue.qsize()) :
# handle = self._handlequeue.get()
# handle.wait()
#for i in self._handlequeue :
# handle = self._handlequeue.pop(0)
# handle.wait()
# Step 0 is called for parameter initialization after parameter broadcast
if self._size > 1 and self._step > 0:
# if it is the final training step, wait for the completion of all tensors
if self._step == self._final_step:
self._logger.debug("final step {}, waiting for allreduce completion.".format(self._final_step))
while not self.event_queue.empty():
time.sleep(0.001)
loss = None
if closure is not None:
loss = closure()
self._step += 1
return loss
else:
# SGD.step() will be triggered when user calls hvd.broadcast_optimizer_sate()
#super(self._opt.__class__, self._opt).step()
self._opt.step()
self._step += 1
#for i in self._handlequeue :
# handle = self._handlequeue.pop(0)
# #p.data = p_cpu.data.cuda()
# handle.wait()
#self._opt.step()
#self._step += 1
def zero_grad(self):
"""Override the default zero_grad function
Clears the gradients of all optimized :class:`torch.Tensor` s.
"""
self._logger.debug("{} calls zero_grad() of step {}".format(self._desc, self._step))
if self._size > 1 and self._step > 0:
return
else:
self._opt.zero_grad()
def allreduce_grad_async(self, tensor, name):
"""Call horovod API to allreduce gradient asynchronously
Arguments:
tensor: The tensor to be allreduced.
name: The name of the tensor.
Returns:
an allreduce handle and context
"""
#ctx = tensor.type()
ctx = name
#print(f'{self._desc} before allreduce {name} : {torch.sum(tensor)}')
#with open(f'before_{self._desc}.csv', 'a', newline='') as f:
# writer = csv.writer(f)
# writer.writerow([name, torch.sum(tensor).item()])
handle = dist.all_reduce(tensor,async_op=True)
self._handlequeue.put(handle)
return handle, ctx
def _acquire_lock(self, lock):
lock.acquire()
def _wait_lock(self, lock, condition):
if lock.locked():
None
else :
with condition :
condition.wait()
def _release_lock(self, lock, condition):
lock.release()
with condition :
condition.notify_all()
def _poll_FSDP(self):
print(self.comm_stream)
count = 0
with torch.cuda.stream(self.comm_stream):
while True :
for comm in self.schedules:
#print(f"{count} {comm['comm_type']}")
if(comm["comm_type"] == "AG"): #AG recover original parameter
if(self.is_first_itr == True):
None
#for p in comm["params"]:
# #resolving dead lock
# self._wait_lock(self._lazy_init_locks[p], self._lazy_init_conditions[p])
else :
for p in comm["params"]:
self._wait_lock(self._ag_locks[p], self._ag_conditions[p])
#for p in comm["params"]:
# self._wait_lock(self._ag_locks[p], self._ag_conditions[p])
for p in comm["params"]:
p_data = p.data.to(p._full_param_padded.device)
p_size = p._full_param_padded.size()
p_data.new_zeros(p_size)
p._full_param_padded.storage().resize_(p_size.numel())
output_tensor = p._full_param_padded
dist._all_gather_base(output_tensor, p_data)
#p._full_param_padded.storage().resize_(0)
p.data = output_tensor
p.data = p.data[: p._orig_size.numel()].view(p._orig_size)
p_data = None
for p in comm["params"]:
print(f"AG {self._parameter_names[p]}{p.data.shape}")
self._release_lock(self._ag_locks[p], self._forward_conditions[p])
#print(f"all_gather {self._parameter_names[p]}")
elif(comm["comm_type"] == "AG_FSDP"): #between forward and backward
print(f"all gather fsdp before wait lock {self._parameter_names[p]}")
for p in comm["params"]:
self._wait_lock(self._ag_fsdp_locks[p], self._ag_fsdp_conditions[p])
#print(f"all gather fsdp after wait lock {self._parameter_names[p]}")
for p in comm["params"]:
p_data = p.data.to(p._full_param_padded.device)
p_size = p._full_param_padded.size()
p_data.new_zeros(p_size)
p._full_param_padded.storage().resize_(p_size.numel())
output_tensor = p._full_param_padded
dist._all_gather_base(output_tensor, p_data)
#p._full_param_padded.storage().resize_(0)
p.data = output_tensor
p.data = p.data[: p._orig_size.numel()].view(p._orig_size)
print(p.data.shape)
p_data = None
for p in comm["params"]:
self._release_lock(self._ag_fsdp_locks[p], self._backward_conditions[p])
elif(comm["comm_type"] == "RS"): #after backward
for p in comm["params"]:
self._wait_lock(self._rs_locks[p], self._rs_conditions[p])
for p in comm["params"]:
grad = p.grad.data
grad_chunks = chunk_and_pad(grad, 2)
p.grad.data = torch.zeros_like(grad_chunks[0]).type(p.grad.dtype).to(p.device)
dist.reduce_scatter(p.grad, grad_chunks, async_op=False)
#print(f"output p.grad[0] {p.grad.shape} {torch.sum(p.grad)}")
#p.grad = None
self._post_reduction_hook(p, p.grad.data)
self._finalize_parameters(p)
self._adam(p)
#
self._zero_one_grad(p)
#p.grad = None
grad = None
grad_chunks = None
for p in comm["params"]:
self._release_lock(self._rs_locks[p], self._ag_conditions[p])
self._acquire_lock(self._ag_locks[p])
count += 1
if(self.is_first_itr == True):
self.is_first_itr = False
#comms with tensor partition
def _poll(self):
"""Poll the completion of the tensor's backward or allreduce from a FIFO event_queue"""
with torch.cuda.stream(self.comm_stream):
while True:
#for p,g,h,ctx,cb in list(self.event_queue.queue):
# print(f'{ctx} {self._parameter_names[p]}')
for param_group in self.param_groups:
backward_params = param_group['params'][::]
for p in backward_params:
#print(p)
#while self.partition_counts[p] > self.done_counts[p] :
if self._locks[p].locked():
#print(f"_poll {self._parameter_names[p]}")
#handle = dist.all_reduce(p.grad, async_op=True)
#self._handlequeue.append(handle)
dist.all_reduce(p.grad)
else :
with self._conditions[p] :
self._conditions[p].wait()
#handle = dist.all_reduce(p.grad, async_op=True)
#self._handlequeue.append(handle)
dist.all_reduce(p.grad)
p.grad = p.grad / 2
print(f"output p.grad[0] {p.grad.shape} {torch.sum(p.grad)}")
#self._finalize_parameters(p)
self._adam(p)
#self._sgd(p)
self._zero_one_grad(p)
#p.grad = None
self._locks[p].release()
with self._forward_conditions[p] :
self._forward_conditions[p].notify_all()
print(f"after backward {torch.cuda.memory_allocated() / 1024 /1024}")
def _poll_wfbp(self):
"""Poll the completion of the tensor's backward or allreduce from a FIFO event_queue"""
with torch.cuda.stream(self.comm_stream):
while True:
#for p,g,h,ctx,cb in list(self.event_queue.queue):
# print(f'{ctx} {self._parameter_names[p]}')
for param_group in self.param_groups:
backward_params = param_group['params'][::]
for p in backward_params:
#print(p)
if self._locks[p].locked():
#print(f"_poll {self._parameter_names[p]}")
#handle = dist.all_reduce(p.grad, async_op=True)
#self._handlequeue.append(handle)
dist.all_reduce(p.grad)
else :
with self._conditions[p] :
self._conditions[p].wait()
#handle = dist.all_reduce(p.grad, async_op=True)
#self._handlequeue.append(handle)
dist.all_reduce(p.grad)
p.grad = p.grad / 2
print(f"output p.grad[0] {p.grad.shape} {torch.sum(p.grad)}")
#self._finalize_parameters(p)
self._adam(p)
#self._sgd(p)
self._zero_one_grad(p)
#p.grad = None
self._locks[p].release()
with self._forward_conditions[p] :
self._forward_conditions[p].notify_all()
print(f"after backward {torch.cuda.memory_allocated() / 1024 /1024}")
def _poll_RS(self):
"""Poll the completion of the tensor's backward or allreduce from a FIFO event_queue"""
with torch.cuda.stream(self.comm_stream):
while True:
#for p,g,h,ctx,cb in list(self.event_queue.queue):
# print(f'{ctx} {self._parameter_names[p]}')
for param_group in self.param_groups:
#backward_params = param_group['params'][::-1]
backward_params = param_group['params'][::]
for p in backward_params:
#print(f"enter poll {self._parameter_names[p]}")
if self._locks[p].locked():
None
#grad = p.grad.data
#grad_chunks = chunk_and_pad(grad, 2)
#p.grad.data = torch.zeros_like(grad_chunks[0]).type(p.grad.dtype).to(p.device)
#print(f"reduce scatter lock {self._parameter_names[p]}")
#dist.reduce_scatter(p.grad, grad_chunks, async_op=False)
else :
with self._conditions[p] :
#print("wait in poll!!")
self._conditions[p].wait()
#grad = p.grad.data
#grad_chunks = chunk_and_pad(grad, 2)
#p.grad.data = torch.zeros_like(grad_chunks[0]).type(p.grad.dtype).to(p.device)
#print(f"reduce scatter condition {self._parameter_names[p]}")
#dist.reduce_scatter(p.grad, grad_chunks, async_op=False)
grad = p.grad.data
grad_chunks = chunk_and_pad(grad, 2)
p.grad.data = torch.zeros_like(grad_chunks[0]).type(p.grad.dtype).to(p.device)
###
dist.reduce_scatter(p.grad, grad_chunks, async_op=False)
print(f"output p.grad[0] {p.grad.shape} {torch.sum(p.grad)}")
#p.grad = None
self._post_reduction_hook(p, p.grad.data)
self._finalize_parameters(p)
self._adam(p)
#self._sgd(p)
#
self._zero_one_grad(p)
#p.grad = None
grad = None
grad_chunks = None
#torch.cuda.synchronize()
#p_data = p.data.to(p._full_param_padded.device)
#p_size = p._full_param_padded.size()
#p_data.new_zeros(p_size)
#p._full_param_padded.storage().resize_(p_size.numel())
#output_tensor = p._full_param_padded
#print(f"all_gather output tensor {output_tensor.shape}")
#print(f"all gather input tensor {p_data.shape}")
#dist._all_gather_base(output_tensor, p_data)
#p._full_param_padded.storage().resize_(0)
#p_data = None
#p_data = None
#print(f"after update {p.data.shape} {torch.sum(p.data)}")
#output_tensor.record_stream(torch.cuda.current_stream())
self._locks[p].release()
with self._forward_conditions[p] :
self._forward_conditions[p].notify_all()
#print(f"release lock {self._parameter_names[p]}")
print(f"after backward {torch.cuda.memory_allocated() / 1024 /1024}")
def _post_reduction_hook(self, param: Parameter, reduced_grad: torch.Tensor) -> None:
"""Hook to call on each param after the reduce-scatter."""
if param._is_sharded:
# Accumulate into the gradient shard.
if getattr(param, "_saved_grad_shard", None) is None:
param._saved_grad_shard = reduced_grad.data
else:
assert (
param._saved_grad_shard.shape == reduced_grad.shape
), f"{param._saved_grad_shard.shape} vs {reduced_grad.shape}"
param._saved_grad_shard.data += reduced_grad.data
reduced_grad = param._saved_grad_shard.data
def _finalize_parameters(self, p):
if not p.requires_grad:
return
if hasattr(p, "_shard_bwd_hook"):
assert len(p._shard_bwd_hook) == 2, len(p._shard_bwd_hook)
p._shard_bwd_hook[1].remove()
delattr(p, "_shard_bwd_hook")
# Leave the gradient accumulation state as-is if not synchronizing this pass. This ensures p.grad
# remains the unsharded gradient accumulated from prior no-sync passes, and p._saved_grad_shard
# remains the sharded gradient from the last synchronized pass. This also allows interleaved no-sync and
# sync passes, if desired.
#if not self._require_backward_grad_sync:
# return
# Parameter and gradient devices must match.
if hasattr(p, "_cpu_grad"):
assert p.device == torch.device("cpu")
p.grad = p._cpu_grad
elif hasattr(p, "_saved_grad_shard"):
assert p.device == p._saved_grad_shard.device
p.grad = p._saved_grad_shard
if hasattr(p, "_saved_grad_shard"):
delattr(p, "_saved_grad_shard")
def _zero_one_grad(self, p):
"""Clears the gradient of one variable as PyTorch accumulates gradients by default.
Arguments:
p: the parameter.
"""
if p.grad is not None:
# Not sure whether to do detach_ or not
p.grad.detach_()
p.grad.zero_()
"""Below are the implementations of optimizers, e.g., SGD, Adam."""
def _sgd(self, p):
"""Performs a single optimization step using SGD optimizer on a parameter.
Arguments:
p: The parameter to be updated.
"""
# TODO: support other optimizers later, or figure out a walk around way
for group in self.param_groups:
weight_decay = group['weight_decay']
momentum = group['momentum']
dampening = group['dampening']
nesterov = group['nesterov']
for gp in group['params']:
if self._parameter_names[p] != self._parameter_names[gp] or gp.shape != p.shape:
continue
self._logger.debug("{} is updating {}".format(self._desc, self._parameter_names[p]))
if p.grad is None:
continue
d_p = p.grad.data
#print(self._parameter_names[p])
#print(p.data.shape)
if weight_decay != 0:
d_p.add_(weight_decay, p.data)
if momentum != 0:
param_state = self.state[p]
if 'momentum_buffer' not in param_state:
buf = param_state['momentum_buffer'] = torch.zeros_like(p.data)
buf.mul_(momentum).add_(d_p)
else:
buf = param_state['momentum_buffer']
buf.mul_(momentum).add_(1 - dampening, d_p)
if nesterov:
d_p = d_p.add(momentum, buf)
else:
d_p = buf
p.data.add_(-group['lr'], d_p)
#d_p = None
#print(f"p.shape & data {p.shape} {p.data[0]}")
break
def _adam(self, p):
"""Performs a single optimization step using Adam optimizer on a parameter.
Arguments:
p: The parameter to be updated.
"""
for group in self.param_groups:
for gp in group['params']:
if self._parameter_names[p] != self._parameter_names[gp] or gp.shape != p.shape:
continue
self._logger.debug("{} is updating {}".format(self._desc, self._parameter_names[p]))
if p.grad is None:
continue
grad = p.grad.data
if grad.is_sparse:
raise RuntimeError('Adam does not support sparse gradients, please consider SparseAdam instead')
amsgrad = group['amsgrad']
state = self.state[p]
# State initialization
if len(state) == 0:
state['step'] = 0
# Exponential moving average of gradient values
state['exp_avg'] = torch.zeros_like(p.data)
# Exponential moving average of squared gradient values
state['exp_avg_sq'] = torch.zeros_like(p.data)
if amsgrad:
# Maintains max of all exp. moving avg. of sq. grad. values
state['max_exp_avg_sq'] = torch.zeros_like(p.data)
exp_avg, exp_avg_sq = state['exp_avg'], state['exp_avg_sq']
if amsgrad:
max_exp_avg_sq = state['max_exp_avg_sq']
beta1, beta2 = group['betas']
state['step'] += 1
if group['weight_decay'] != 0:
grad.add_(group['weight_decay'], p.data)
# Decay the first and second moment running average coefficient
exp_avg.mul_(beta1).add_(1 - beta1, grad)
exp_avg_sq.mul_(beta2).addcmul_(1 - beta2, grad, grad)
if amsgrad:
# Maintains the maximum of all 2nd moment running avg. till now
torch.max(max_exp_avg_sq, exp_avg_sq, out=max_exp_avg_sq)
# Use the max. for normalizing running avg. of gradient
denom = max_exp_avg_sq.sqrt().add_(group['eps'])
else:
denom = exp_avg_sq.sqrt().add_(group['eps'])
bias_correction1 = 1 - beta1 ** state['step']
bias_correction2 = 1 - beta2 ** state['step']
step_size = group['lr'] * math.sqrt(bias_correction2) / bias_correction1
p.data.addcdiv_(-step_size, exp_avg, denom)
break
def init():
"""Replace _register_hook() function in hvd._DistributedOptimizer with empty function."""
def hijack(obj, func_name):
orig_func = getattr(obj, func_name)
print("hijack function {}".format(orig_func))
def wrapped_func(*args, **kwargs):
print("function {} is hijacked to do nothing.".format(orig_func))
return
setattr(obj, func_name, wrapped_func)
#hijack(hvd._DistributedOptimizer, '_register_hooks')