| 1 | # SPDX-License-Identifier: Apache-2.0 |
| 2 | # SPDX-FileCopyrightText: Copyright contributors to the vLLM project |
| 3 | """Benchmark the fused MoE-LoRA fast path (one-shot) vs two-kernel baseline. |
| 4 | |
| 5 | The "one_shot" provider goes through `vllm.lora.ops.triton_ops.fused_moe_lora` |
| 6 | which dispatches to the single-kernel one-shot implementation when |
| 7 | fully_sharded=False (the prefill default). |
| 8 | |
| 9 | The "two_kernel" provider drives `fused_moe_lora_shrink` + `fused_moe_lora_expand` |
| 10 | directly, bypassing the dispatch and matching the legacy two-kernel path's |
| 11 | work distribution. This isolates the win from kernel fusion. |
| 12 | |
| 13 | Run: |
| 14 | .venv/bin/python -m benchmarks.kernels.benchmark_fused_moe_lora_one_shot |
| 15 | .venv/bin/python -m benchmarks.kernels.benchmark_fused_moe_lora_one_shot \\ |
| 16 | --model qwen3moe |
| 17 | """ |
| 18 | |
| 19 | from __future__ import annotations |
| 20 | |
| 21 | import argparse |
| 22 | import os |
| 23 | import random |
| 24 | |
| 25 | import torch |
| 26 | |
| 27 | from vllm import _custom_ops as ops |
| 28 | from vllm.lora.ops.triton_ops import ( |
| 29 | fused_moe_lora, |
| 30 | fused_moe_lora_expand, |
| 31 | fused_moe_lora_shrink, |
| 32 | ) |
| 33 | from vllm.triton_utils import triton |
| 34 | |
| 35 | DTYPE = torch.bfloat16 |
| 36 | DEVICE = "cuda" |
| 37 | |
| 38 | |
| 39 | # ----- input fabrication ----------------------------------------------------- |
| 40 | |
| 41 | |
| 42 | def _round_up(x: int, base: int) -> int: |
| 43 | return ((x + base - 1) // base) * base |
| 44 | |
| 45 | |
| 46 | def _ceildiv(x: int, y: int) -> int: |
| 47 | return (x + y - 1) // y |
| 48 | |
| 49 | |
| 50 | def _assign_loras(num_tokens: int, num_sequences: int, max_loras: int) -> torch.Tensor: |
| 51 | tokens_per_seq = num_tokens // num_sequences |
| 52 | rem = num_tokens % num_sequences |
| 53 | out = torch.empty(num_tokens, dtype=torch.int32) |
| 54 | start = 0 |
| 55 | for i in range(num_sequences): |
| 56 | end = start + tokens_per_seq + (1 if i < rem else 0) |
| 57 | out[start:end] = random.randint(0, max_loras - 1) |
| 58 | start = end |
| 59 | return out |
| 60 | |
| 61 | |
| 62 | def _assign_experts(num_tokens: int, num_experts: int, top_k: int): |
| 63 | expert_indices = torch.empty((num_tokens, top_k), dtype=torch.int32) |
| 64 | for i in range(num_tokens): |
| 65 | expert_indices[i] = torch.randperm(num_experts)[:top_k] |
| 66 | weights = torch.rand((num_tokens, top_k), dtype=torch.float32) |
| 67 | weights = weights / weights.sum(dim=1, keepdim=True) |
| 68 | return expert_indices, weights |
| 69 | |
| 70 | |
| 71 | def _make_inputs( |
| 72 | M: int, |
| 73 | K: int, |
| 74 | N_per_slice: int, |
| 75 | rank: int, |
| 76 | num_experts: int, |
| 77 | top_k: int, |
| 78 | max_loras: int, |
| 79 | num_slices: int, |
| 80 | block_size_m: int, |
| 81 | ): |
| 82 | """Mirrors the production caller's tensor layout.""" |
| 83 | torch.manual_seed(0) |
| 84 | random.seed(0) |
| 85 | |
| 86 | num_sequences = max(1, min(M, 8)) |
| 87 | topk_ids_cpu, topk_weights_cpu = _assign_experts(M, num_experts, top_k) |
| 88 | token_lora_cpu = _assign_loras(M, num_sequences, max_loras) |
| 89 | lora_ids_cpu = torch.full((max_loras + 1,), -1, dtype=torch.int32) |
| 90 | uniq = torch.unique(token_lora_cpu, sorted=True) |
| 91 | lora_ids_cpu[: uniq.size(0)].copy_(uniq) |
| 92 | |
| 93 | topk_ids = topk_ids_cpu.to(DEVICE) |
| 94 | topk_weights = topk_weights_cpu.to(device=DEVICE, dtype=DTYPE) |
| 95 | token_lora_mapping = token_lora_cpu.to(DEVICE) |
| 96 | lora_ids = lora_ids_cpu.to(DEVICE) |
| 97 | adapter_enabled = torch.ones(max_loras + 1, dtype=torch.int32, device=DEVICE) |
| 98 | |
| 99 | lora_a = [ |
| 100 | torch.randn((max_loras, num_experts, rank, K), dtype=DTYPE, device=DEVICE) |
| 101 | / max(K, 1) ** 0.5 |
| 102 | for _ in range(num_slices) |
| 103 | ] |
| 104 | lora_b = [ |
| 105 | torch.randn( |
| 106 | (max_loras, num_experts, N_per_slice, rank), |
| 107 | dtype=DTYPE, |
| 108 | device=DEVICE, |
| 109 | ) |
| 110 | / max(rank, 1) ** 0.5 |
| 111 | for _ in range(num_slices) |
| 112 | ] |
| 113 | hidden = torch.randn((M, K), dtype=DTYPE, device=DEVICE) |
| 114 | out_template = torch.zeros( |
| 115 | (M, top_k, num_slices * N_per_slice), dtype=DTYPE, device=DEVICE |
| 116 | ) |
| 117 | |
| 118 | # Sorted-path metadata (the prefill default). |
| 119 | max_pad = topk_ids.numel() + num_experts * (block_size_m - 1) |
| 120 | max_pad = _round_up(max_pad, block_size_m) |
| 121 | max_blocks = _ceildiv(max_pad, block_size_m) |
| 122 | sorted_token_ids = torch.empty( |
| 123 | (max_loras * max_pad,), dtype=torch.int32, device=DEVICE |
| 124 | ) |
| 125 | expert_ids = torch.empty( |
| 126 | (max_loras * max_blocks,), dtype=torch.int32, device=DEVICE |
| 127 | ) |
| 128 | num_post = torch.empty((max_loras,), dtype=torch.int32, device=DEVICE) |
| 129 | ops.moe_lora_align_block_size( |
| 130 | topk_ids, |
| 131 | token_lora_mapping, |
| 132 | num_experts, |
| 133 | block_size_m, |
| 134 | max_loras, |
| 135 | max_pad, |
| 136 | max_blocks, |
| 137 | sorted_token_ids, |
| 138 | expert_ids, |
| 139 | num_post, |
| 140 | adapter_enabled, |
| 141 | lora_ids, |
| 142 | ) |
| 143 | expert_ids = expert_ids.view(max_loras, -1).contiguous() |
| 144 | sorted_token_ids = sorted_token_ids.view(max_loras, -1).contiguous() |
| 145 | num_active = torch.tensor([max_loras + 1], dtype=torch.int32, device="cpu") |
| 146 | |
| 147 | return dict( |
| 148 | hidden=hidden, |
| 149 | lora_a=lora_a, |
| 150 | lora_b=lora_b, |
| 151 | topk_weights=topk_weights, |
| 152 | sorted_token_ids=sorted_token_ids, |
| 153 | expert_ids=expert_ids, |
| 154 | num_post=num_post, |
| 155 | token_lora_mapping=token_lora_mapping, |
| 156 | lora_ids=lora_ids, |
| 157 | num_active=num_active, |
| 158 | adapter_enabled=adapter_enabled, |
| 159 | out_template=out_template, |
| 160 | # bookkeeping |
| 161 | M=M, |
| 162 | K=K, |
| 163 | N_per_slice=N_per_slice, |
| 164 | rank=rank, |
| 165 | num_experts=num_experts, |
| 166 | top_k=top_k, |
| 167 | max_loras=max_loras, |
| 168 | num_slices=num_slices, |
| 169 | block_size_m=block_size_m, |
| 170 | ) |
| 171 | |
| 172 | |
| 173 | # ----- providers ------------------------------------------------------------- |
| 174 | |
| 175 | |
| 176 | def _run_one_shot(inp: dict): |
| 177 | """Drive `fused_moe_lora` with fully_sharded=False -> one-shot fast path.""" |
| 178 | out = inp["out_template"].clone() |
| 179 | fused_moe_lora( |
| 180 | out, |
| 181 | inp["hidden"], |
| 182 | inp["lora_a"], |
| 183 | inp["lora_b"], |
| 184 | inp["topk_weights"], |
| 185 | inp["sorted_token_ids"], |
| 186 | inp["expert_ids"], |
| 187 | inp["num_post"], |
| 188 | inp["token_lora_mapping"], |
| 189 | inp["rank"], |
| 190 | inp["top_k"], |
| 191 | inp["lora_ids"], |
| 192 | inp["num_active"], |
| 193 | inp["adapter_enabled"], |
| 194 | inp["block_size_m"], |
| 195 | 64, |
| 196 | 32, |
| 197 | 8, |
| 198 | 4, |
| 199 | 3, |
| 200 | 1, |
| 201 | inp["block_size_m"], |
| 202 | 64, |
| 203 | 32, |
| 204 | 8, |
| 205 | 4, |
| 206 | 3, |
| 207 | 1, |
| 208 | False, |
| 209 | False, |
| 210 | 0, |
| 211 | ) |
| 212 | return out |
| 213 | |
| 214 | |
| 215 | def _run_two_kernel(inp: dict): |
| 216 | """Drive `fused_moe_lora_shrink` + `fused_moe_lora_expand` directly, |
| 217 | bypassing the dispatch. Matches the legacy two-kernel work distribution. |
| 218 | """ |
| 219 | M = inp["M"] |
| 220 | top_k = inp["top_k"] |
| 221 | rank = inp["rank"] |
| 222 | num_slices = inp["num_slices"] |
| 223 | N_per_slice = inp["N_per_slice"] |
| 224 | K = inp["K"] |
| 225 | num_experts = inp["num_experts"] |
| 226 | block_m = inp["block_size_m"] |
| 227 | |
| 228 | intermediate = torch.zeros((num_slices, M, top_k, rank), dtype=DTYPE, device=DEVICE) |
| 229 | out = inp["out_template"].clone() |
| 230 | EM = inp["sorted_token_ids"].shape[1] |
| 231 | num_tokens = M * top_k |
| 232 | |
| 233 | fused_moe_lora_shrink( |
| 234 | intermediate, |
| 235 | inp["hidden"], |
| 236 | inp["lora_a"], |
| 237 | inp["topk_weights"], |
| 238 | inp["sorted_token_ids"], |
| 239 | inp["expert_ids"], |
| 240 | inp["num_post"], |
| 241 | inp["token_lora_mapping"], |
| 242 | top_k, |
| 243 | inp["lora_ids"], |
| 244 | inp["adapter_enabled"], |
| 245 | torch.device(DEVICE), |
| 246 | rank, |
| 247 | M, |
| 248 | EM, |
| 249 | K, |
| 250 | num_tokens, |
| 251 | num_experts, |
| 252 | num_slices, |
| 253 | block_m, |
| 254 | 64, |
| 255 | 32, |
| 256 | 8, |
| 257 | 4, |
| 258 | 3, |
| 259 | 1, |
| 260 | inp["num_active"], |
| 261 | False, |
| 262 | ) |
| 263 | fused_moe_lora_expand( |
| 264 | out, |
| 265 | intermediate, |
| 266 | inp["lora_b"], |
| 267 | inp["topk_weights"], |
| 268 | inp["sorted_token_ids"], |
| 269 | inp["expert_ids"], |
| 270 | inp["num_post"], |
| 271 | inp["token_lora_mapping"], |
| 272 | top_k, |
| 273 | inp["lora_ids"], |
| 274 | inp["adapter_enabled"], |
| 275 | torch.device(DEVICE), |
| 276 | rank, |
| 277 | M, |
| 278 | EM, |
| 279 | K, |
| 280 | num_tokens, |
| 281 | num_experts, |
| 282 | num_slices, |
| 283 | rank, |
| 284 | N_per_slice, |
| 285 | block_m, |
| 286 | 64, |
| 287 | 32, |
| 288 | 8, |
| 289 | 4, |
| 290 | 3, |
| 291 | 1, |
| 292 | inp["num_active"], |
| 293 | False, |
| 294 | 0, |
| 295 | ) |
| 296 | return out |
| 297 | |
| 298 | |
| 299 | PROVIDER_FNS = { |
| 300 | "one_shot": _run_one_shot, |
| 301 | "two_kernel": _run_two_kernel, |
| 302 | } |
| 303 | |
| 304 | |
| 305 | # ----- model presets --------------------------------------------------------- |
| 306 | |
| 307 | |
| 308 | MODEL_PRESETS: dict[str, dict] = { |
| 309 | # Mixtral-8x7B style: E=8, top_k=2, hidden=4096, intermediate=14336 |
| 310 | "mixtral": dict( |
| 311 | K=4096, |
| 312 | N_per_slice=7168, |
| 313 | num_experts=8, |
| 314 | top_k=2, |
| 315 | max_loras=4, |
| 316 | num_slices=2, |
| 317 | block_size_m=64, |
| 318 | ), |
| 319 | # Qwen3-MoE / DeepSeek-V2 style: E=64, top_k=8, hidden=2048, inter=1408 |
| 320 | "qwen3moe": dict( |
| 321 | K=2048, |
| 322 | N_per_slice=1408, |
| 323 | num_experts=64, |
| 324 | top_k=8, |
| 325 | max_loras=4, |
| 326 | num_slices=2, |
| 327 | block_size_m=64, |
| 328 | ), |
| 329 | # GLM-5.1 (zai-org/GLM-5.1-FP8): E=256, top_k=8, hidden=6144, |
| 330 | # moe_intermediate=2048 |
| 331 | "glm5_1": dict( |
| 332 | K=6144, |
| 333 | N_per_slice=2048, |
| 334 | num_experts=256, |
| 335 | top_k=8, |
| 336 | max_loras=4, |
| 337 | num_slices=2, |
| 338 | block_size_m=64, |
| 339 | ), |
| 340 | } |
| 341 | |
| 342 | |
| 343 | M_RANGE = [16, 64, 256, 1024, 4096, 16384] |
| 344 | RANK_RANGE = [8, 16, 32, 64] |
| 345 | |
| 346 | |
| 347 | def get_benchmark(model: str, max_loras: int | None = None): |
| 348 | preset = dict(MODEL_PRESETS[model]) |
| 349 | if max_loras is not None: |
| 350 | preset["max_loras"] = max_loras |
| 351 | |
| 352 | @triton.testing.perf_report( |
| 353 | triton.testing.Benchmark( |
| 354 | x_names=["M", "rank"], |
| 355 | x_vals=[(M, R) for M in M_RANGE for R in RANK_RANGE], |
| 356 | line_arg="provider", |
| 357 | line_vals=list(PROVIDER_FNS.keys()), |
| 358 | line_names=["one_shot (fused)", "two_kernel (legacy)"], |
| 359 | styles=[("red", "-"), ("blue", "-")], |
| 360 | ylabel="ms", |
| 361 | plot_name=f"fused_moe_lora-{model}-loras{preset['max_loras']}", |
| 362 | args={"preset": preset}, |
| 363 | ) |
| 364 | ) |
| 365 | def benchmark(M, rank, provider, preset): |
| 366 | inp = _make_inputs( |
| 367 | M=M, |
| 368 | K=preset["K"], |
| 369 | N_per_slice=preset["N_per_slice"], |
| 370 | rank=rank, |
| 371 | num_experts=preset["num_experts"], |
| 372 | top_k=preset["top_k"], |
| 373 | max_loras=preset["max_loras"], |
| 374 | num_slices=preset["num_slices"], |
| 375 | block_size_m=preset["block_size_m"], |
| 376 | ) |
| 377 | fn = PROVIDER_FNS[provider] |
| 378 | quantiles = [0.5, 0.2, 0.8] |
| 379 | ms, min_ms, max_ms = triton.testing.do_bench( |
| 380 | lambda: fn(inp), quantiles=quantiles |
| 381 | ) |
| 382 | return ms, max_ms, min_ms |
| 383 | |
| 384 | return benchmark |
| 385 | |
| 386 | |
| 387 | # ----- correctness sanity --------------------------------------------------- |
| 388 | |
| 389 | |
| 390 | def calculate_diff(model: str, M: int, rank: int, max_loras: int | None = None): |
| 391 | preset = dict(MODEL_PRESETS[model]) |
| 392 | if max_loras is not None: |
| 393 | preset["max_loras"] = max_loras |
| 394 | inp = _make_inputs( |
| 395 | M=M, |
| 396 | K=preset["K"], |
| 397 | N_per_slice=preset["N_per_slice"], |
| 398 | rank=rank, |
| 399 | num_experts=preset["num_experts"], |
| 400 | top_k=preset["top_k"], |
| 401 | max_loras=preset["max_loras"], |
| 402 | num_slices=preset["num_slices"], |
| 403 | block_size_m=preset["block_size_m"], |
| 404 | ) |
| 405 | out_one = _run_one_shot(inp) |
| 406 | out_two = _run_two_kernel(inp) |
| 407 | max_abs = (out_one.float() - out_two.float()).abs().max().item() |
| 408 | print( |
| 409 | f" model={model:<9} M={M:<6} rank={rank:<3} " |
| 410 | f"max|one_shot - two_kernel|={max_abs:.4g} " |
| 411 | f"ref|max|={out_two.float().abs().max().item():.3g}" |
| 412 | ) |
| 413 | if max_abs <= 5e-2: |
| 414 | print(" ✅ outputs match within bf16 tolerance") |
| 415 | else: |
| 416 | print(" ❌ outputs differ beyond expected bf16 noise") |
| 417 | |
| 418 | |
| 419 | # ----- main ------------------------------------------------------------------ |
| 420 | |
| 421 | |
| 422 | if __name__ == "__main__": |
| 423 | parser = argparse.ArgumentParser() |
| 424 | parser.add_argument( |
| 425 | "--model", |
| 426 | type=str, |
| 427 | default="mixtral", |
| 428 | choices=list(MODEL_PRESETS.keys()), |
| 429 | help="Model preset to sweep", |
| 430 | ) |
| 431 | parser.add_argument( |
| 432 | "--save-path", |
| 433 | type=str, |
| 434 | default="./configs/fused_moe_lora_one_shot/", |
| 435 | help="Directory to save benchmark results", |
| 436 | ) |
| 437 | parser.add_argument( |
| 438 | "--check-only", |
| 439 | action="store_true", |
| 440 | help="Run correctness sanity check only, no perf sweep", |
| 441 | ) |
| 442 | parser.add_argument( |
| 443 | "--max-loras", |
| 444 | type=int, |
| 445 | default=None, |
| 446 | help="Override max_loras in the model preset (number of LoRA adapters " |
| 447 | "active in the batch). Defaults to the preset's value.", |
| 448 | ) |
| 449 | args = parser.parse_args() |
| 450 | |
| 451 | print(f"Correctness check ({args.model}):") |
| 452 | calculate_diff(args.model, M=256, rank=32, max_loras=args.max_loras) |
| 453 | if args.check_only: |
| 454 | raise SystemExit(0) |
| 455 | |
| 456 | effective_max_loras = ( |
| 457 | args.max_loras |
| 458 | if args.max_loras is not None |
| 459 | else MODEL_PRESETS[args.model]["max_loras"] |
| 460 | ) |
| 461 | print(f"\nGPU: {torch.cuda.get_device_name()}") |
| 462 | print(f"Model preset: {args.model} max_loras={effective_max_loras}\n") |
| 463 | benchmark = get_benchmark(args.model, max_loras=args.max_loras) |
| 464 | os.makedirs(args.save_path, exist_ok=True) |
| 465 | benchmark.run(print_data=True, save_path=args.save_path) |