flash-attention/tests/models/test_opt.py
2023-08-18 20:59:35 -07:00

84 lines
3.6 KiB
Python

import re
import pytest
import torch
from flash_attn.models.gpt import GPTLMHeadModel
from flash_attn.models.opt import opt_config_to_gpt2_config, remap_state_dict_hf_opt
from flash_attn.utils.pretrained import state_dict_from_pretrained
from transformers import OPTConfig
from transformers.models.opt.modeling_opt import OPTForCausalLM
@pytest.mark.parametrize(
"model_name", ["facebook/opt-125m", "facebook/opt-350m", "facebook/opt-1.3b"]
)
# @pytest.mark.parametrize('model_name', ["facebook/opt-350m"])
def test_opt_state_dict(model_name):
config = opt_config_to_gpt2_config(OPTConfig.from_pretrained(model_name))
pretrained_state_dict = remap_state_dict_hf_opt(state_dict_from_pretrained(model_name), config)
model = GPTLMHeadModel(config)
state_dict = model.state_dict()
assert state_dict.keys() == pretrained_state_dict.keys()
for k in state_dict.keys():
assert state_dict[k].shape == pretrained_state_dict[k].shape
@pytest.mark.parametrize(
"model_name", ["facebook/opt-125m", "facebook/opt-350m", "facebook/opt-1.3b"]
)
# @pytest.mark.parametrize('model_name', ["facebook/opt-350m"])
def test_opt_optimized(model_name):
"""Check that our implementation of OPT (without all optimizations enabled) matches the
HF implementation: the output of our forward pass in fp16 should be around the same as the HF
forward pass in fp16, when compared to the HF forward pass in fp32.
"""
dtype = torch.float16
device = "cuda"
config = opt_config_to_gpt2_config(OPTConfig.from_pretrained(model_name))
config.use_flash_attn = True
config.fused_bias_fc = True
config.fused_mlp = True
config.fused_dropout_add_ln = True
# Only prenorm supports residual_in_fp32
config.residual_in_fp32 = getattr(config, "prenorm", True)
config.pad_vocab_size_multiple = 8
model = GPTLMHeadModel.from_pretrained(model_name, config, device=device, dtype=dtype)
model_ref = OPTForCausalLM.from_pretrained(model_name).to(device=device)
model_hf = OPTForCausalLM.from_pretrained(model_name, torch_dtype=dtype).to(device=device)
model.eval()
model_ref.eval()
model_hf.eval()
torch.manual_seed(0)
batch_size = 2
max_seqlen = 256
seqlens = torch.randint(max_seqlen // 2, max_seqlen + 1, (batch_size,), device="cuda")
input_ids = torch.randint(
0, config.vocab_size, (batch_size, max_seqlen), dtype=torch.long, device="cuda"
)
if model_name != "facebook/opt-350m": # The OPT-350m projects the embeddings to dimension 512
out = model.transformer(input_ids)
out_hf = model_hf.model(input_ids).last_hidden_state
out_ref = model_ref.model(input_ids).last_hidden_state
print(f"Output max diff: {(out - out_ref).abs().max().item()}")
print(f"Output mean diff: {(out - out_ref).abs().mean().item()}")
print(f"HF fp16 max diff: {(out_hf - out_ref).abs().max().item()}")
print(f"HF fp16 mean diff: {(out_hf - out_ref).abs().mean().item()}")
assert (out - out_ref).abs().max().item() < 3 * (out_hf - out_ref).abs().max().item()
logits = model(input_ids).logits
logits_hf = model_hf(input_ids).logits
logits_ref = model_ref(input_ids).logits
print(f"Logits max diff: {(logits - logits_ref).abs().max().item()}")
print(f"Logits mean diff: {(logits - logits_ref).abs().mean().item()}")
print(f"HF fp16 max diff: {(logits_hf - logits_ref).abs().max().item()}")
print(f"HF fp16 mean diff: {(logits_hf - logits_ref).abs().mean().item()}")
assert (logits - logits_ref).abs().max().item() < 3 * (
logits_hf - logits_ref
).abs().max().item()