[shardformer] Sequence Parallelism Optimization (#5533)

* sequence parallel optimization

* validate sequence parallel in llama (code to be polished)

* shardformer api writing

* integrate sequence parallel in ShardFormer

* fix pp bugs and sp bugs for LlaMa model

* integrating ring-based sequence parallelism into ShardFormer

* [sequence parallelism]: Add fused megatron function

* integrating ring-based sequence parallelism into ShardFormer

---------

Co-authored-by: linsj20 <linsj20@mails.tsinghua.edu.cn>

* fix bugs when useing sp and flashattention together

* fix operation function name

* support flash attention for ulysses-style sp

* clarify sp process group

* fix compatibility bugs in moe plugin

* fix fused linear bugs

* fix linear layer test

* support gpt model all-to-all sp

* modify shard data dimension (meant to be dim=-1)

* support megtron-style sp and distributed attn for llama model

* [shardformer] add megatron sp to llama

* support llama7B 128k with distributed attention

* [shardformer] robustness enhancement

* add block attn

* sp mode 1: keep input as a complete sequence

* fix sp compatability

* finish sp mode 3 support for gpt

* using all_to_all_single when batch size is 1

* support mode 2 sp in gpt2 (#5)

* [shardformer] add megatron sp to llama

* support llama7B 128k with distributed attention

* [shardformer] robustness enhancement

* add block attn

* sp mode 1: keep input as a complete sequence

* fix sp compatability

* refactor ring implementation

* support mode 2 sp in gpt2

* polish code

* enable distributed attn mask when using sp mode 2 and 3 in llama

* automatically enable flash attn when using sp mode 2 and 3 in llama

* inplace attn mask

* add zero2 support for sequence parallel

* polish code

* fix bugs

* fix gemini checkpoint io

* loose tensor checking atol and rtol

* add comment

* fix llama layernorm grad

* fix zero grad

* fix zero grad

* fix conflict

* update split and gather auto grad func

* sequence parallel: inside text split (#6)

* polish code (part 1)

* polish code (part 2)

* polish code (part 2.5)

* polish code (part 3)

* sequence parallel: inside text split

* miscellaneous minor fixes

* polish code

* fix ulysses style ZeRO

* sequence parallel: inside text split

* miscellaneous minor fixes

* disaggregate sp group and dp group for  sp

* fix llama and gpt sp

* polish code

* move ulysses grad sync to ddp (#9)

* remove zero_stage and unbind the grad sync for alltoall sp

* add 2d group creation test

* move ulysses grad sync to ddp

* add 2d group creation test

* remove useless code

* change shard config not to enable sp when enable_all_optimizations

* add sp warnings for several model

* remove useless code

---------

Co-authored-by: linsj20 <linsj20@mails.tsinghua.edu.cn>
This commit is contained in:
Zhongkai Zhao
2024-04-03 17:15:47 +08:00
committed by GitHub
parent 7e0ec5a85c
commit 8e412a548e
33 changed files with 1630 additions and 256 deletions

View File

@@ -2,6 +2,8 @@ import os
import pytest
import torch
import torch.distributed as dist
from torch.testing import assert_close
import colossalai
from colossalai.logging import disable_existing_loggers
@@ -46,6 +48,26 @@ def check_forward_backward(model_fn, data_gen_fn, output_transform_fn, loss_fn,
row_layer_for_check = ["layers[0].self_attn.q_proj", "embed_tokens"]
col_layer_for_check = ["layers[0].self_attn.o_proj"]
# Here we check the grad of layernorm because an all-reduce operation should be performed during sequence parallelism
norm_layer_for_check = ["layers[0].input_layernorm", "layers[0].post_attention_layernorm"]
# During pipeline parallelism, we cannot get the grad of norm layer during first stage, so we only check this when pp is not enbaled
if stage_manager is None:
norm_layer_for_check.append("norm")
# Check the grad when using ZeRO-1 and ZeRO-2
if (
booster.plugin.zero_stage in [1, 2]
and booster.plugin.shard_config.enable_sequence_parallelism
and booster.plugin.shard_config.sequence_parallelism_mode == "all_to_all"
):
for p1, p2 in zip(llama_model.parameters(), sharded_optimizer._master_param_groups_of_current_rank[0]):
working_p = sharded_optimizer._param_store.master_to_working_param[id(p2)]
grads = sharded_optimizer._grad_store.get_partitioned_gradients_by_param_id(0, id(working_p))
grad_index = 0 if sharded_optimizer._partition_grads else sharded_optimizer._local_rank
grad = grads[grad_index]
sharded_grad = p1.grad.view(-1).chunk(dist.get_world_size())[dist.get_rank()]
assert_close(sharded_grad, grad[: sharded_grad.shape[0]], atol=5e-3, rtol=5e-3, check_dtype=False)
# Save gradient tensors for comparison between the original model and the sharded model before optimizer step.
grads_to_check = {}
@@ -60,8 +82,19 @@ def check_forward_backward(model_fn, data_gen_fn, output_transform_fn, loss_fn,
col_layer_grads = get_grad_tensors_for_check(
llama_model, shard_llama_model, col_layer_for_check, tp_group, atol=atol, rtol=rtol, dim=1, verbose=False
)
norm_layer_grads = get_grad_tensors_for_check(
llama_model,
shard_llama_model,
norm_layer_for_check,
tp_group,
atol=atol,
rtol=rtol,
dim=1,
verbose=False,
)
grads_to_check.update(col_layer_grads)
grads_to_check.update(row_layer_grads)
grads_to_check.update(norm_layer_grads)
# optimizer executes step
org_optimizer.step()
@@ -98,6 +131,74 @@ def check_forward_backward(model_fn, data_gen_fn, output_transform_fn, loss_fn,
@parameterize(
"test_config",
[
{
"tp_size": 2,
"pp_size": 1,
"num_microbatches": 1,
"enable_sequence_parallelism": True,
"sequence_parallelism_mode": "ring",
"enable_flash_attention": True,
"use_lazy_init": True,
"zero_stage": 2,
"precision": "fp16",
"initial_scale": 1,
},
{
"tp_size": 4,
"pp_size": 1,
"num_microbatches": 1,
"enable_sequence_parallelism": True,
"sequence_parallelism_mode": "ring",
"enable_flash_attention": False,
"use_lazy_init": True,
"precision": "fp32",
"initial_scale": 1,
},
{
"tp_size": 4,
"pp_size": 1,
"num_microbatches": 1,
"enable_sequence_parallelism": True,
"sequence_parallelism_mode": "split_gather",
"enable_flash_attention": False,
"use_lazy_init": True,
"precision": "fp16",
"initial_scale": 1,
},
{
"tp_size": 1,
"pp_size": 1,
"sp_size": 2,
"num_microbatches": 1,
"enable_sequence_parallelism": True,
"sequence_parallelism_mode": "all_to_all",
"use_lazy_init": True,
"precision": "fp16",
"initial_scale": 1,
},
{
"tp_size": 1,
"pp_size": 1,
"sp_size": 2,
"num_microbatches": 1,
"enable_sequence_parallelism": True,
"sequence_parallelism_mode": "all_to_all",
"use_lazy_init": True,
"zero_stage": 2,
"precision": "fp16",
"initial_scale": 1,
},
{
"tp_size": 1,
"pp_size": 1,
"num_microbatches": 1,
"enable_sequence_parallelism": True,
"sequence_parallelism_mode": "all_to_all",
"enable_flash_attention": False,
"use_lazy_init": True,
"precision": "fp16",
"initial_scale": 1,
},
{
"tp_size": 2,
"pp_size": 2,