| 1 | # SPDX-License-Identifier: Apache-2.0 |
| 2 | # SPDX-FileCopyrightText: Copyright contributors to the vLLM project |
| 3 | """Benchmark the RDNAHybridW4A16LinearKernel across decode and prefill shapes. |
| 4 | |
| 5 | Usage: |
| 6 | python benchmark_int4_gemm.py |
| 7 | python benchmark_int4_gemm.py --models Qwen/Qwen3-4B |
| 8 | python benchmark_int4_gemm.py --group-size 128 |
| 9 | """ |
| 10 | |
| 11 | import argparse |
| 12 | import copy |
| 13 | import itertools |
| 14 | import os |
| 15 | |
| 16 | import torch |
| 17 | |
| 18 | from vllm.triton_utils import triton |
| 19 | |
| 20 | # --------------------------------------------------------------------------- |
| 21 | # Weight shapes: [K, N], TP_SPLIT_DIM |
| 22 | # --------------------------------------------------------------------------- |
| 23 | WEIGHT_SHAPES = { |
| 24 | "Qwen/Qwen3-4B": [ |
| 25 | ([2560, 3840], 1), # qkv_proj |
| 26 | ([2560, 2560], 0), # o_proj |
| 27 | ([2560, 19456], 1), # gate_up_proj |
| 28 | ([9728, 2560], 0), # down_proj |
| 29 | ], |
| 30 | "Qwen/Qwen2.5-7B-Instruct": [ |
| 31 | ([3584, 4608], 1), |
| 32 | ([3584, 3584], 0), |
| 33 | ([3584, 37888], 1), |
| 34 | ([18944, 3584], 0), |
| 35 | ], |
| 36 | "trymirai/SmolLM2-1.7B-Instruct-AWQ": [ |
| 37 | ([2048, 6144], 1), # qkv_proj |
| 38 | ([2048, 2048], 0), # o_proj |
| 39 | ([2048, 16384], 1), # gate_up_proj |
| 40 | ([8192, 2048], 0), # down_proj |
| 41 | ], |
| 42 | "RedHatAI/Qwen3-8B-quantized.w4a16": [ |
| 43 | ([4096, 6144], 1), # qkv_proj |
| 44 | ([4096, 4096], 0), # o_proj |
| 45 | ([4096, 24576], 1), # gate_up_proj |
| 46 | ([12288, 4096], 0), # down_proj |
| 47 | ], |
| 48 | } |
| 49 | |
| 50 | |
| 51 | # --------------------------------------------------------------------------- |
| 52 | # Weight packing |
| 53 | # --------------------------------------------------------------------------- |
| 54 | def prepare_hybrid_weights(K, N, group_size, device="cuda"): |
| 55 | """Create random weights for benchmarking. |
| 56 | |
| 57 | Returns (w_q_skinny, w_s_skinny, w_fp16, w_zp). The triton path derives |
| 58 | its int32 view from w_q_skinny, so no separate int32 buffer is returned. |
| 59 | """ |
| 60 | num_groups = K // group_size |
| 61 | |
| 62 | # Random packed weights — actual values don't matter for throughput |
| 63 | w_q_skinny_i32 = torch.randint( |
| 64 | 0, 2**31, (N, K // 8), dtype=torch.int32, device=device |
| 65 | ) |
| 66 | w_q_skinny = w_q_skinny_i32.view(torch.int8).contiguous() |
| 67 | w_s_skinny = torch.randn(N, num_groups, dtype=torch.float16, device=device) * 0.01 |
| 68 | |
| 69 | # Raw per-group zero-points for asymmetric benchmarks |
| 70 | w_zp = torch.randint(0, 16, (N, num_groups), dtype=torch.int32, device=device).to( |
| 71 | torch.float16 |
| 72 | ) |
| 73 | |
| 74 | # FP16 baseline for F.linear |
| 75 | w_fp16 = torch.randn(N, K, dtype=torch.float16, device=device) * 0.01 |
| 76 | |
| 77 | return w_q_skinny, w_s_skinny, w_fp16, w_zp |
| 78 | |
| 79 | |
| 80 | # --------------------------------------------------------------------------- |
| 81 | # Benchmark |
| 82 | # --------------------------------------------------------------------------- |
| 83 | PROVIDERS = ["torch-fp16", "hybrid-w4a16", "hybrid-w4a16-zp"] |
| 84 | |
| 85 | |
| 86 | @triton.testing.perf_report( |
| 87 | triton.testing.Benchmark( |
| 88 | x_names=["batch_size"], |
| 89 | x_vals=[1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096], |
| 90 | x_log=False, |
| 91 | line_arg="provider", |
| 92 | line_vals=PROVIDERS, |
| 93 | line_names=PROVIDERS, |
| 94 | ylabel="TFLOP/s (larger is better)", |
| 95 | plot_name="FP16 vs Hybrid W4A16", |
| 96 | args={}, |
| 97 | ) |
| 98 | ) |
| 99 | def benchmark(batch_size, provider, N, K, group_size, weights): |
| 100 | M = batch_size |
| 101 | device = "cuda" |
| 102 | dtype = torch.float16 |
| 103 | a = torch.randn((M, K), device=device, dtype=dtype) |
| 104 | |
| 105 | quantiles = [0.5, 0.2, 0.8] |
| 106 | |
| 107 | if provider == "torch-fp16": |
| 108 | w_fp16 = weights["w_fp16"] |
| 109 | ms, min_ms, max_ms = triton.testing.do_bench_cudagraph( |
| 110 | lambda: torch.nn.functional.linear(a, w_fp16), |
| 111 | quantiles=quantiles, |
| 112 | ) |
| 113 | elif provider in ("hybrid-w4a16", "hybrid-w4a16-zp"): |
| 114 | from vllm.model_executor.kernels.linear.mixed_precision import ( |
| 115 | rdna_hybrid_w4a16 as _k, |
| 116 | ) |
| 117 | |
| 118 | _rdna_hybrid_w4a16_apply_impl = _k._rdna_hybrid_w4a16_apply_impl |
| 119 | from vllm.utils.platform_utils import num_compute_units |
| 120 | |
| 121 | w = weights |
| 122 | cu_count = num_compute_units() |
| 123 | use_zp = provider == "hybrid-w4a16-zp" |
| 124 | |
| 125 | def run(): |
| 126 | return _rdna_hybrid_w4a16_apply_impl( |
| 127 | a, |
| 128 | w["w_q_skinny"], |
| 129 | w["w_s_skinny"], |
| 130 | w["w_zp"] if use_zp else None, |
| 131 | None, # bias |
| 132 | cu_count, |
| 133 | group_size, |
| 134 | ) |
| 135 | |
| 136 | ms, min_ms, max_ms = triton.testing.do_bench_cudagraph( |
| 137 | run, |
| 138 | quantiles=quantiles, |
| 139 | ) |
| 140 | else: |
| 141 | return 0.0, 0.0, 0.0 |
| 142 | |
| 143 | to_tflops = lambda t_ms: (2 * M * N * K) * 1e-12 / (t_ms * 1e-3) |
| 144 | return to_tflops(ms), to_tflops(max_ms), to_tflops(min_ms) |
| 145 | |
| 146 | |
| 147 | def prepare_shapes(args): |
| 148 | KN_model_names = [] |
| 149 | for model, tp_size in itertools.product(args.models, args.tp_sizes): |
| 150 | for KN, tp_dim in copy.deepcopy(WEIGHT_SHAPES[model]): |
| 151 | KN[tp_dim] //= tp_size |
| 152 | KN.append(model) |
| 153 | KN_model_names.append(KN) |
| 154 | return KN_model_names |
| 155 | |
| 156 | |
| 157 | if __name__ == "__main__": |
| 158 | parser = argparse.ArgumentParser( |
| 159 | description="Benchmark RDNAHybridW4A16LinearKernel" |
| 160 | ) |
| 161 | parser.add_argument( |
| 162 | "--models", |
| 163 | nargs="+", |
| 164 | type=str, |
| 165 | default=["Qwen/Qwen3-4B"], |
| 166 | choices=list(WEIGHT_SHAPES.keys()), |
| 167 | ) |
| 168 | parser.add_argument("--tp-sizes", nargs="+", type=int, default=[1]) |
| 169 | parser.add_argument("--group-size", type=int, default=128) |
| 170 | parser.add_argument("--save-path", type=str, default=None) |
| 171 | args = parser.parse_args() |
| 172 | |
| 173 | for K, N, model in prepare_shapes(args): |
| 174 | group_size = args.group_size |
| 175 | print(f"\n{'=' * 70}") |
| 176 | print(f"{model}, N={N} K={K}, group_size={group_size}") |
| 177 | print(f"{'=' * 70}") |
| 178 | |
| 179 | w_q_skinny, w_s_skinny, w_fp16, w_zp = prepare_hybrid_weights(K, N, group_size) |
| 180 | |
| 181 | weights = { |
| 182 | "w_q_skinny": w_q_skinny, |
| 183 | "w_s_skinny": w_s_skinny, |
| 184 | "w_fp16": w_fp16, |
| 185 | "w_zp": w_zp, |
| 186 | } |
| 187 | |
| 188 | save_path = args.save_path or f"bench_int4_res_n{N}_k{K}" |
| 189 | os.makedirs(save_path, exist_ok=True) |
| 190 | benchmark.run( |
| 191 | print_data=True, |
| 192 | show_plots=False, |
| 193 | save_path=save_path, |
| 194 | N=N, |
| 195 | K=K, |
| 196 | group_size=group_size, |
| 197 | weights=weights, |
| 198 | ) |
| 199 | |
| 200 | print("\nBenchmark finished!") |