Files
sglang/python/sglang/test/test_cutlass_moe.py

282 lines
9.4 KiB
Python
Executable File

import argparse
import time
import torch
import triton # Added import
import triton.testing # Added import
from transformers import AutoConfig
from sglang.srt.layers.moe.cutlass_moe import cutlass_fused_experts_fp8
from sglang.srt.layers.moe.fused_moe_triton.fused_moe import fused_experts
from sglang.srt.layers.moe.moe_runner.base import MoeRunnerConfig
# Copy from: https://github.com/deepseek-ai/DeepGEMM/blob/main/deep_gemm/utils.py
def calc_diff(x, y):
x, y = x.double(), y.double()
denominator = (x * x + y * y).sum()
sim = 2 * (x * y).sum() / denominator
return 1 - sim
def get_model_config(tp_size: int):
config = AutoConfig.from_pretrained(
"deepseek-ai/deepseek-R1", trust_remote_code=True
)
E = config.n_routed_experts
topk = config.num_experts_per_tok
intermediate_size = config.moe_intermediate_size
shard_intermediate_size = 2 * intermediate_size // tp_size
return {
"num_experts": E,
"topk": topk,
"hidden_size": config.hidden_size,
"shard_intermediate_size": shard_intermediate_size,
"dtype": config.torch_dtype,
"block_shape": config.quantization_config["weight_block_size"],
}
def to_fp8(tensor: torch.Tensor) -> torch.Tensor:
"""Converts tensor to FP8 E4M3, scaling values to fit the range."""
finfo = torch.finfo(torch.float8_e4m3fn)
# Calculate max absolute value safely
max_val = torch.max(torch.abs(tensor))
# Avoid division by zero if tensor is all zeros
if max_val == 0:
scale_factor = 1.0
else:
# Scale factor to bring the max value to finfo.max
scale_factor = finfo.max / max_val
# Apply scaling
scaled_tensor = tensor * scale_factor
# Clamp and convert
fp8_tensor = scaled_tensor.clamp(min=finfo.min, max=finfo.max).to(
dtype=torch.float8_e4m3fn
)
return fp8_tensor
def run_test(tp_size, batch_size, model_config, check=False):
print(f"\n--- Batch Size: {batch_size} ---")
torch.set_default_device("cuda")
torch.cuda.manual_seed_all(42) # For reproducible random numbers
E = model_config["num_experts"]
topk = model_config["topk"]
H = model_config["hidden_size"]
I = model_config["shard_intermediate_size"]
block_shape = model_config["block_shape"] # Tuple (BLOCK_N, BLOCK_K)
dtype = model_config["dtype"] # e.g., torch.bfloat16
print(
f"Config: E={E}, topk={topk}, H={H}, I_shard={I}, dtype={dtype}, block_shape={block_shape}"
)
# --- Input Data ---
# Use bf16/fp16 for input activation based on model config
x = torch.randn((batch_size, H), device="cuda", dtype=dtype)
# --- Weights (Generate in higher precision, then convert to FP8) ---
# Generate weights suitable for FP8 conversion (e.g., scaled appropriately)
w1_hp = torch.randn((E, I, H), device="cuda", dtype=torch.float32)
w2_hp = torch.randn((E, H, I // 2), device="cuda", dtype=torch.float32)
w1 = to_fp8(w1_hp)
w2 = to_fp8(w2_hp)
# --- Scales for FP8 Weights ---
block_n, block_k = block_shape
# Calculate number of blocks needed
w1_blocks_dim1 = (I + block_n - 1) // block_n
w1_blocks_dim2 = (H + block_k - 1) // block_k
w2_blocks_dim1 = (H + block_n - 1) // block_n
w2_blocks_dim2 = (I // 2 + block_k - 1) // block_k
# Scales are typically float32 or float16/bfloat16
scale_dtype = torch.float32 # Or dtype if scales match model dtype
w1_scale = torch.full(
(E, w1_blocks_dim1, w1_blocks_dim2), 1, device="cuda", dtype=scale_dtype
) # Avoid zero scales
w2_scale = torch.full(
(E, w2_blocks_dim1, w2_blocks_dim2), 1, device="cuda", dtype=scale_dtype
) # Avoid zero scales
# --- Routing Information ---
topk_weights = torch.softmax(
torch.rand(batch_size, topk, device="cuda", dtype=dtype), dim=-1
)
topk_ids = torch.randint(0, E, (batch_size, topk), dtype=torch.int32, device="cuda")
a1_strides = torch.full((E,), H, dtype=torch.int64, device="cuda")
c1_strides = torch.full((E,), I, dtype=torch.int64, device="cuda")
a2_strides = torch.full((E,), I // 2, dtype=torch.int64, device="cuda")
c2_strides = torch.full((E,), H, dtype=torch.int64, device="cuda")
workspace = torch.empty(
(7182 * 1024), device="cuda", dtype=torch.uint8
) # Allocate sufficient workspace
# Pointer arrays (often filled by the kernel or a prep step, but needed as args)
a_ptrs = torch.empty((E,), dtype=torch.int64, device="cuda")
b_ptrs = torch.empty((E,), dtype=torch.int64, device="cuda")
out_ptrs = torch.empty((E,), dtype=torch.int64, device="cuda")
a_scales_ptrs = torch.empty((E,), dtype=torch.int64, device="cuda")
b_scales_ptrs = torch.empty((E,), dtype=torch.int64, device="cuda")
expert_offsets = torch.empty((E + 1,), dtype=torch.int32, device="cuda")
problem_sizes1 = torch.empty((E, 3), dtype=torch.int32, device="cuda")
problem_sizes2 = torch.empty((E, 3), dtype=torch.int32, device="cuda")
# --- Lambdas for Benchmarking ---
cutlass_lambda = lambda: cutlass_fused_experts_fp8(
x,
w1.transpose(1, 2), # Transposed
w2.transpose(1, 2), # Transposed
w1_scale.transpose(1, 2),
w2_scale.transpose(1, 2),
topk_weights,
topk_ids,
a1_strides,
c1_strides,
a2_strides,
c2_strides,
workspace,
a_ptrs,
b_ptrs,
out_ptrs,
a_scales_ptrs,
b_scales_ptrs,
expert_offsets,
problem_sizes1,
problem_sizes2,
)
# Note: Triton expects non-transposed weights
moe_config = MoeRunnerConfig(inplace=False)
triton_lambda = lambda: fused_experts(
x,
w1,
w2,
(topk_weights, topk_ids, "dummy"),
moe_config,
use_fp8_w8a8=True,
w1_scale=w1_scale,
w2_scale=w2_scale,
block_shape=block_shape,
)
# --- Warmup ---
print("Warming up...")
for _ in range(10):
_ = cutlass_lambda()
_ = triton_lambda()
torch.cuda.synchronize()
# --- Benchmarking ---
quantiles = [0.5, 0.2, 0.8]
print(f"Benchmarking Cutlass fused_experts...")
cutlass_ms, cutlass_min, cutlass_max = triton.testing.do_bench_cudagraph(
cutlass_lambda, rep=1000, quantiles=quantiles
)
print(f"Benchmarking Triton fused_experts...")
triton_ms, triton_min, triton_max = triton.testing.do_bench_cudagraph(
triton_lambda, rep=1000, quantiles=quantiles
)
print(
f"Cutlass fused_experts time: {cutlass_ms:.3f} ms (median) [{cutlass_min:.3f} - {cutlass_max:.3f}]"
)
print(
f"Triton fused_experts time: {triton_ms:.3f} ms (median) [{triton_min:.3f} - {triton_max:.3f}]"
)
# --- Correctness Check ---
if check:
print("Running correctness check...")
with torch.no_grad():
# Run CUTLASS version (requires transposed weights)
y_cutlass = cutlass_fused_experts_fp8(
x,
w1.transpose(1, 2), # Transposed
w2.transpose(1, 2), # Transposed
w1_scale.transpose(1, 2),
w2_scale.transpose(1, 2),
topk_weights,
topk_ids,
a1_strides,
c1_strides,
a2_strides,
c2_strides,
workspace,
a_ptrs,
b_ptrs,
out_ptrs,
a_scales_ptrs,
b_scales_ptrs,
expert_offsets,
problem_sizes1,
problem_sizes2,
)
# Run Triton version (requires original shape weights, use inplace=False)
y_triton = fused_experts(
x,
w1, # Original shape
w2, # Original shape
(topk_weights, topk_ids, "dummy"),
moe_config,
use_fp8_w8a8=True,
w1_scale=w1_scale,
w2_scale=w2_scale,
block_shape=block_shape,
)
diff = calc_diff(y_cutlass, y_triton)
print(f"Diff: {diff:.6f}")
# Tolerance might need adjustment based on FP8 specifics and kernel differences
# FP8 comparisons often require higher tolerance than FP16/BF16
assert diff < 1e-4, f"Diff too high! {diff}"
print("Correctness check passed.")
def main(tp_size=8, batch_sizes=[1, 4, 8, 16, 32, 64, 128, 256, 512], check=False):
model_config = get_model_config(tp_size)
print("Model Config:", model_config)
for batch_size in batch_sizes:
run_test(tp_size, batch_size, model_config, check)
if __name__ == "__main__":
parser = argparse.ArgumentParser()
parser.add_argument("--tp-size", type=int, default=8, help="Tensor Parallel size")
parser.add_argument(
"--batch-sizes",
type=int,
nargs="+",
default=[
1,
4,
8,
16,
32,
64,
128,
256,
512,
1024,
2048,
4096,
8192,
], # Adjusted default
help="List of batch sizes to test",
)
parser.add_argument("--check", action="store_true", help="Enable check mode")
args = parser.parse_args()
print(f"Running benchmarks with TP size: {args.tp_size}")
print(f"Testing batch sizes: {args.batch_sizes}")
main(tp_size=args.tp_size, batch_sizes=args.batch_sizes, check=args.check)