Files
vllm/vllm/_custom_ops.py
Philipp Moritz eace8bf0b9 [Kernel] FP8 support for MoE kernel / Mixtral (#4244)
This PR is the first step towards fixing https://github.com/vllm-project/vllm/pull/3208

It implements dynamic per-tensor scaling (see https://github.com/vllm-project/vllm/pull/4118), so users do not need to compute activation scales on a calibration dataset and they also don't need to convert their model checkpoints. It is enough to specify the `quantization="fp8"` argument. You can try out the PR like this:

```python
from vllm import LLM, SamplingParams

prompts = [
    "Hello, my name is",
    "The president of the United States is",
    "The capital of France is",
    "The future of AI is",
]
sampling_params = SamplingParams(temperature=0.8, top_p=0.95)

llm = LLM(model="mistralai/Mixtral-8x7B-Instruct-v0.1", tensor_parallel_size=2, quantization="fp8")

outputs = llm.generate(prompts, sampling_params)

# Print the outputs.
for output in outputs:
    prompt = output.prompt
    generated_text = output.outputs[0].text
    print(f"Prompt: {prompt!r}, Generated text: {generated_text!r}")
```

**Performance**: For this PR, the focus is on making the code clean (while still trying to get reasonable performance), there is a bunch of optimizations that we will submit as a follow up PR that significantly improve the performance (similar to the numbers in https://github.com/vllm-project/vllm/pull/3954). With this PR, the results are as follows:

<img width="725" alt="Screenshot 2024-04-21 at 1 31 50 PM" src="https://github.com/vllm-project/vllm/assets/113316/d8fe1118-07a0-4d4e-8530-37a77d465a03">


**Accuracy**: The accuracy with this PR on MMLU on `mistralai/Mixtral-8x7B-v0.1` is as follows:

```
|      Groups      |Version|Filter|n-shot|Metric|Value |   |Stderr|
|------------------|-------|------|-----:|------|-----:|---|-----:|
|mmlu              |N/A    |none  |     0|acc   |0.7018|±  |0.0036|
| - humanities     |N/A    |none  |     5|acc   |0.6472|±  |0.0065|
| - other          |N/A    |none  |     5|acc   |0.7673|±  |0.0072|
| - social_sciences|N/A    |none  |     5|acc   |0.8099|±  |0.0070|
| - stem           |N/A    |none  |     5|acc   |0.6131|±  |0.0083|
```
this compares favorably with the fp16 results which are
```
|      Groups      |Version|Filter|n-shot|Metric|Value |   |Stderr|
|------------------|-------|------|-----:|------|-----:|---|-----:|
|mmlu              |N/A    |none  |     0|acc   |0.7020|±  |0.1313|
| - humanities     |N/A    |none  |     5|acc   |0.6425|±  |0.1349|
| - other          |N/A    |none  |     5|acc   |0.7744|±  |0.1038|
| - social_sciences|N/A    |none  |     5|acc   |0.8131|±  |0.0695|
| - stem           |N/A    |none  |     5|acc   |0.6108|±  |0.1383|
```

Happy hacking!
2024-04-24 01:18:23 +00:00

202 lines
6.5 KiB
Python

from typing import Dict, Optional, Tuple
import torch
try:
from vllm._C import cache_ops as vllm_cache_ops
from vllm._C import ops as vllm_ops
except ImportError:
pass
# activation ops
def silu_and_mul(out: torch.Tensor, x: torch.Tensor) -> None:
vllm_ops.silu_and_mul(out, x)
def gelu_and_mul(out: torch.Tensor, x: torch.Tensor) -> None:
vllm_ops.gelu_and_mul(out, x)
def gelu_tanh_and_mul(out: torch.Tensor, x: torch.Tensor) -> None:
vllm_ops.gelu_tanh_and_mul(out, x)
def gelu_fast(out: torch.Tensor, x: torch.Tensor) -> None:
vllm_ops.gelu_fast(out, x)
def gelu_new(out: torch.Tensor, x: torch.Tensor) -> None:
vllm_ops.gelu_new(out, x)
# page attention ops
def paged_attention_v1(
out: torch.Tensor,
query: torch.Tensor,
key_cache: torch.Tensor,
value_cache: torch.Tensor,
num_kv_heads: int,
scale: float,
block_tables: torch.Tensor,
context_lens: torch.Tensor,
block_size: int,
max_context_len: int,
alibi_slopes: Optional[torch.Tensor],
kv_cache_dtype: str,
kv_scale: float,
) -> None:
vllm_ops.paged_attention_v1(out, query, key_cache, value_cache,
num_kv_heads, scale, block_tables,
context_lens, block_size, max_context_len,
alibi_slopes, kv_cache_dtype, kv_scale)
def paged_attention_v2(
out: torch.Tensor,
exp_sum: torch.Tensor,
max_logits: torch.Tensor,
tmp_out: torch.Tensor,
query: torch.Tensor,
key_cache: torch.Tensor,
value_cache: torch.Tensor,
num_kv_heads: int,
scale: float,
block_tables: torch.Tensor,
context_lens: torch.Tensor,
block_size: int,
max_context_len: int,
alibi_slopes: Optional[torch.Tensor],
kv_cache_dtype: str,
kv_scale: float,
) -> None:
vllm_ops.paged_attention_v2(out, exp_sum, max_logits, tmp_out, query,
key_cache, value_cache, num_kv_heads, scale,
block_tables, context_lens, block_size,
max_context_len, alibi_slopes, kv_cache_dtype,
kv_scale)
# pos encoding ops
def rotary_embedding(
positions: torch.Tensor,
query: torch.Tensor,
key: torch.Tensor,
head_size: int,
cos_sin_cache: torch.Tensor,
is_neox: bool,
) -> None:
vllm_ops.rotary_embedding(positions, query, key, head_size, cos_sin_cache,
is_neox)
def batched_rotary_embedding(positions: torch.Tensor, query: torch.Tensor,
key: torch.Tensor, head_size: int,
cos_sin_cache: torch.Tensor, is_neox: bool,
rot_dim: int,
cos_sin_cache_offsets: torch.Tensor) -> None:
vllm_ops.batched_rotary_embedding(positions, query, key, head_size,
cos_sin_cache, is_neox, rot_dim,
cos_sin_cache_offsets)
# layer norm ops
def rms_norm(out: torch.Tensor, input: torch.Tensor, weight: torch.Tensor,
epsilon: float) -> None:
vllm_ops.rms_norm(out, input, weight, epsilon)
def fused_add_rms_norm(input: torch.Tensor, residual: torch.Tensor,
weight: torch.Tensor, epsilon: float) -> None:
vllm_ops.fused_add_rms_norm(input, residual, weight, epsilon)
# quantization ops
# awq
def awq_dequantize(qweight: torch.Tensor, scales: torch.Tensor,
zeros: torch.Tensor, split_k_iters: int, thx: int,
thy: int) -> torch.Tensor:
return vllm_ops.awq_dequantize(qweight, scales, zeros, split_k_iters, thx,
thy)
def awq_gemm(input: torch.Tensor, qweight: torch.Tensor, qzeros: torch.Tensor,
scales: torch.Tensor, split_k_iters: int) -> torch.Tensor:
return vllm_ops.awq_gemm(input, qweight, qzeros, scales, split_k_iters)
# gptq
def gptq_gemm(a: torch.Tensor, b_q_weight: torch.Tensor,
b_gptq_qzeros: torch.Tensor, b_gptq_scales: torch.Tensor,
b_g_idx: torch.Tensor, use_exllama: bool,
bit: int) -> torch.Tensor:
return vllm_ops.gptq_gemm(a, b_q_weight, b_gptq_qzeros, b_gptq_scales,
b_g_idx, use_exllama, bit)
def gptq_shuffle(q_weight: torch.Tensor, q_perm: torch.Tensor,
bit: int) -> None:
vllm_ops.gptq_shuffle(q_weight, q_perm, bit)
# squeezellm
def squeezellm_gemm(vec: torch.Tensor, mat: torch.Tensor, mul: torch.Tensor,
lookup_table: torch.Tensor) -> None:
vllm_ops.squeezellm_gemm(vec, mat, mul, lookup_table)
# marlin
def marlin_gemm(a: torch.Tensor, b_q_weight: torch.Tensor,
b_scales: torch.Tensor, workspace: torch.Tensor, size_m: int,
size_n: int, size_k: int) -> torch.Tensor:
return vllm_ops.marlin_gemm(a, b_q_weight, b_scales, workspace, size_m,
size_n, size_k)
# fp8
def scaled_fp8_quant(input: torch.Tensor) -> Tuple[torch.Tensor, torch.Tensor]:
scale = torch.zeros(1, device=input.device, dtype=torch.float32)
output = torch.empty_like(input, dtype=torch.float8_e4m3fn)
vllm_ops.scaled_fp8_quant(output, input, scale)
return output, scale
# moe
def moe_align_block_size(topk_ids: torch.Tensor, num_experts: int,
block_size: int, sorted_token_ids: torch.Tensor,
experts_ids: torch.Tensor,
num_tokens_post_pad: torch.Tensor) -> None:
vllm_ops.moe_align_block_size(topk_ids, num_experts, block_size,
sorted_token_ids, experts_ids,
num_tokens_post_pad)
def reshape_and_cache(
key: torch.Tensor,
value: torch.Tensor,
key_cache: torch.Tensor,
value_cache: torch.Tensor,
slot_mapping: torch.Tensor,
kv_cache_dtype: str,
kv_scale: float,
) -> None:
vllm_cache_ops.reshape_and_cache(key, value, key_cache, value_cache,
slot_mapping, kv_cache_dtype, kv_scale)
def copy_blocks(key_caches: torch.Tensor, value_caches: torch.Tensor,
block_mapping: torch.Tensor) -> None:
vllm_cache_ops.copy_blocks(key_caches, value_caches, block_mapping)
def swap_blocks(src: torch.Tensor, dst: torch.Tensor,
block_mapping: Dict[int, int]) -> None:
vllm_cache_ops.swap_blocks(src, dst, block_mapping)
def convert_fp8(output: torch.Tensor, input: torch.Tensor) -> None:
vllm_cache_ops.convert_fp8(output, input)
#TODO: cuda_utils, custom_ar