[gemini] async grad chunk reduce (all-reduce&reduce-scatter) (#5713)

* [gemini] async grad chunk reduce (all-reduce&reduce-scatter)

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* [gemini] add test

* [gemini] rename func

* [gemini] update llama benchmark

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* [gemini] use tensor counter

* [gemini] change default config in GeminiPlugin and GeminiDDP

* [chore] typo

* [gemini] fix sync issue & add test cases

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
This commit is contained in:
botbw
2024-05-24 10:31:16 +08:00
committed by GitHub
parent 85946d4236
commit 2fc85abf43
11 changed files with 130 additions and 45 deletions

View File

@@ -164,6 +164,8 @@ class Chunk:
self.l2_norm = None
self.grad_chunk = None
# the async all-reduce/reduce-scatter work of this grad chunk (None means sync)
self.grad_reduce_work = None
@property
def memory_usage(self) -> Dict[str, int]:
@@ -244,7 +246,7 @@ class Chunk:
assert self.cuda_shard is not None # only check on CUDA
valid_tensor = self.cuda_shard[: self.valid_end]
return torch.isinf(valid_tensor).any().item() | torch.isnan(valid_tensor).any().item()
return torch.isinf(valid_tensor).any() | torch.isnan(valid_tensor).any()
def set_l2_norm(self) -> None:
"""Record l2 norm of this chunks on CUDA."""
@@ -374,37 +376,49 @@ class Chunk:
if self.is_gathered:
self.__scatter()
def reduce(self):
def reduce(self, async_op: bool = False):
"""Reduce scatter all the gradients. It's an operation done in CUDA."""
# sanity check
assert self.is_gathered
assert self.grad_reduce_work is None
if self.pg_size == 1:
# tricky code here
# just move cuda_global_chunk to cuda_shard
# the communication is not necessary
self.__scatter()
if self.extra_dp_group is not None:
dist.all_reduce(self.cuda_shard, group=self.extra_dp_group)
self.grad_reduce_work = dist.all_reduce(self.cuda_shard, group=self.extra_dp_group, async_op=async_op)
elif self.keep_gathered:
# we use all-reduce here
dist.all_reduce(self.cuda_global_chunk, group=self.torch_pg)
if self.extra_dp_group is not None:
dist.all_reduce(self.cuda_global_chunk, group=self.extra_dp_group)
self.grad_reduce_work = dist.all_reduce(self.cuda_global_chunk, group=self.torch_pg, async_op=async_op)
if self.extra_dp_group is not None: # cannot guranatee the order of multiple all-reduce
self.wait_async_reduce()
self.grad_reduce_work = dist.all_reduce(
self.cuda_global_chunk, group=self.extra_dp_group, async_op=async_op
)
else:
self.cuda_shard = torch.empty(
self.shard_size, dtype=self.dtype, device=get_accelerator().get_current_device()
)
input_list = list(torch.chunk(self.cuda_global_chunk, chunks=self.pg_size, dim=0))
dist.reduce_scatter(self.cuda_shard, input_list, group=self.torch_pg)
self.grad_reduce_work = dist.reduce_scatter(
self.cuda_shard, input_list, group=self.torch_pg, async_op=async_op
)
if self.extra_dp_group is not None:
dist.all_reduce(self.cuda_shard, group=self.extra_dp_group)
self.wait_async_reduce()
self.grad_reduce_work = dist.all_reduce(self.cuda_shard, group=self.extra_dp_group, async_op=async_op)
free_storage(self.cuda_global_chunk)
self.is_gathered = False
self.__update_tensors_state(TensorState.HOLD)
def wait_async_reduce(self) -> None:
if self.grad_reduce_work is not None:
self.grad_reduce_work.wait()
self.grad_reduce_work = None
def tensor_trans_state(self, tensor: torch.Tensor, tensor_state: TensorState) -> None:
"""
Make a transition of the tensor into the next state.