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flash_attn_mma.py
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import argparse
import math
import os
import random
import time
from functools import partial
from typing import Optional
import numpy as np
import torch
from flash_attn import flash_attn_func
from torch import Tensor
from torch.nn import functional as F
from torch.nn.attention import SDPBackend, sdpa_kernel
from torch.utils.cpp_extension import load
torch.set_grad_enabled(False)
torch.set_printoptions(
precision=6, threshold=8, edgeitems=3, linewidth=120, sci_mode=False
)
def get_args():
parser = argparse.ArgumentParser()
parser.add_argument("--no-rand-q", "--no-rq", action="store_true")
parser.add_argument("--no-rand-k", "--no-rk", action="store_true")
parser.add_argument("--no-rand-v", "--no-rv", action="store_true")
parser.add_argument("--no-rand-qkv", "--no-rqkv", action="store_true")
parser.add_argument("--run-torch-unfused", "--torch", action="store_true")
parser.add_argument("--run-torch-sdpa", "--sdpa", action="store_true")
parser.add_argument("--check", action="store_true")
parser.add_argument("--check-all", action="store_true")
parser.add_argument("--show-all", "--show", action="store_true")
parser.add_argument("--show-matrix", action="store_true")
parser.add_argument(
"--only-flops-matmul", "--flops-mm", action="store_true"
)
parser.add_argument(
"--run-acc-f32", "--acc-f32", "--f32", action="store_true"
)
parser.add_argument("--B", type=int, default=None)
parser.add_argument("--H", type=int, default=None)
parser.add_argument("--N", type=int, default=None)
parser.add_argument("--D", type=int, default=None)
parser.add_argument("--seed", type=int, default=None)
parser.add_argument("--sleep", type=float, default=0.05)
parser.add_argument("--debug", action="store_true")
parser.add_argument("--verbose", "--v", action="store_true")
parser.add_argument("--warmup", "--w", type=int, default=1)
parser.add_argument("--iters", "--i", type=int, default=5)
parser.add_argument("--range-k", "--gk", action="store_true")
parser.add_argument("--build-others", "--others", action="store_true")
parser.add_argument(
"--tag-hints", "--tags", "--hints", type=str, default=None
)
return parser.parse_args()
args = get_args()
def set_rand_seed(seed: int = 1):
random.seed(seed)
np.random.seed(seed)
torch.manual_seed(seed)
torch.cuda.manual_seed_all(seed)
def get_device_name():
device_name = torch.cuda.get_device_name(torch.cuda.current_device())
# since we will run GPU on WSL2, so add WSL2 tag.
if "Laptop" in device_name:
device_name += " WSL2"
return device_name
def get_device_capability():
return torch.cuda.get_device_capability(torch.cuda.current_device())
def get_build_sources():
build_sources = []
# Basic
build_sources.append("./mma/basic/flash_attn_mma_split_kv.cu")
build_sources.append("./mma/basic/flash_attn_mma_split_q.cu")
build_sources.append("./mma/basic/flash_attn_mma_share_kv.cu")
build_sources.append("./mma/basic/flash_attn_mma_share_qkv.cu")
build_sources.append("./mma/basic/flash_attn_mma_tiling_qk.cu")
build_sources.append("./mma/basic/flash_attn_mma_tiling_qkv.cu")
build_sources.append("./mma/basic/flash_attn_mma_share_kv_F32F16F16F32.cu")
build_sources.append("./mma/basic/flash_attn_mma_share_qkv_F32F16F16F32.cu")
build_sources.append("./mma/basic/flash_attn_mma_tiling_qk_F32F16F16F32.cu")
build_sources.append(
"./mma/basic/flash_attn_mma_tiling_qkv_F32F16F16F32.cu"
)
# Swizzle
build_sources.append("./mma/swizzle/flash_attn_mma_share_kv_swizzle_q.cu")
build_sources.append("./mma/swizzle/flash_attn_mma_share_kv_swizzle_qk.cu")
build_sources.append("./mma/swizzle/flash_attn_mma_share_kv_swizzle_qkv.cu")
build_sources.append("./mma/swizzle/flash_attn_mma_share_qkv_swizzle_q.cu")
build_sources.append("./mma/swizzle/flash_attn_mma_share_qkv_swizzle_qk.cu")
build_sources.append(
"./mma/swizzle/flash_attn_mma_share_qkv_swizzle_qkv.cu"
)
build_sources.append("./mma/swizzle/flash_attn_mma_tiling_qk_swizzle_q.cu")
build_sources.append("./mma/swizzle/flash_attn_mma_tiling_qk_swizzle_qk.cu")
build_sources.append(
"./mma/swizzle/flash_attn_mma_tiling_qk_swizzle_qkv.cu"
)
build_sources.append("./mma/swizzle/flash_attn_mma_tiling_qkv_swizzle_q.cu")
build_sources.append(
"./mma/swizzle/flash_attn_mma_tiling_qkv_swizzle_qk.cu"
)
build_sources.append(
"./mma/swizzle/flash_attn_mma_tiling_qkv_swizzle_qkv.cu"
)
build_sources.append(
"./mma/swizzle/flash_attn_mma_tiling_qkv_swizzle_q_F32F16F16F32.cu"
)
build_sources.append(
"./mma/swizzle/flash_attn_mma_tiling_qkv_swizzle_qk_F32F16F16F32.cu"
)
build_sources.append(
"./mma/swizzle/flash_attn_mma_tiling_qkv_swizzle_qkv_F32F16F16F32.cu"
)
# Others
if args.build_others:
build_sources.append("./mma/others/flash_attn_mma_share_qkv_Os2g.cu")
build_sources.append(
"./mma/others/flash_attn_mma_share_kv_F32F16F16F32_rr.cu"
)
build_sources.append(
"./mma/others/flash_attn_mma_share_qkv_F32F16F16F32_rr.cu"
)
# Pybind
build_sources.append("./pybind/flash_attn.cc")
return build_sources
def get_project_dir():
return os.path.dirname(
os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
)
project_dir = get_project_dir()
def get_build_cuda_cflags(build_pkg: bool = False):
device_name = get_device_name()
project_dir = get_project_dir()
extra_cuda_cflags = []
extra_cuda_cflags.append("-O3")
extra_cuda_cflags.append("-std=c++17")
extra_cuda_cflags.append("-U__CUDA_NO_HALF_OPERATORS__")
extra_cuda_cflags.append("-U__CUDA_NO_HALF_CONVERSIONS__")
extra_cuda_cflags.append("-U__CUDA_NO_HALF2_OPERATORS__")
extra_cuda_cflags.append("-U__CUDA_NO_BFLOAT16_CONVERSIONS__")
extra_cuda_cflags.append("--expt-relaxed-constexpr")
extra_cuda_cflags.append("--expt-extended-lambda")
extra_cuda_cflags.append("--use_fast_math")
extra_cuda_cflags.append("-DFLASH_ATTN_MMA_DEBUG" if args.debug else "")
extra_cuda_cflags.append(
"-DBUILD_FLASH_ATTN_MMA_OTHERS" if args.build_others else ""
)
extra_cuda_cflags.append(
"-DBUILD_FLASH_ATTN_MMA_L20" if "L20" in device_name else ""
)
extra_cuda_cflags.append(
"-DBUILD_FLASH_ATTN_MMA_4090" if "4090" in device_name else ""
)
extra_cuda_cflags.append(
"-DBUILD_FLASH_ATTN_MMA_3080" if "3080" in device_name else ""
)
extra_cuda_cflags.append(
"-diag-suppress 177" if not build_pkg else "--ptxas-options=-v"
)
extra_cuda_cflags.append(
"-Xptxas -v" if not build_pkg else "--ptxas-options=-O3"
)
extra_cuda_cflags.append(f"-I {project_dir}/kernels/flash-attn")
extra_cuda_cflags.append(f"-I {project_dir}/kernels/flash-attn/utils")
extra_cuda_cflags.append(f"-I {project_dir}/kernels/flash-attn/mma")
extra_cuda_cflags.append(f"-I {project_dir}/kernels/flash-attn/mma/basic")
extra_cuda_cflags.append(f"-I {project_dir}/kernels/flash-attn/mma/swizzle")
extra_cuda_cflags.append(f"-I {project_dir}/kernels/flash-attn/mma/others")
extra_cuda_cflags.append(f"-I {project_dir}/kernels/flash-attn/cutlass")
extra_cuda_cflags.append(f"-I {project_dir}/kernels/flash-attn/pybind")
extra_cuda_cflags.append(f"-I {project_dir}/third-party/cutlass/include")
extra_cuda_cflags.append(
f"-I {project_dir}/third-party/cutlass/tools/util/include"
)
return extra_cuda_cflags
def get_build_cflags():
extra_cflags = []
extra_cflags.append("-std=c++17")
extra_cflags.append(
"-DBUILD_FLASH_ATTN_MMA_OTHERS" if args.build_others else ""
)
return extra_cflags
def pretty_print_line(m: str = "", sep: str = "-", width: int = 150):
res_len = width - len(m)
left_len = int(res_len / 2)
right_len = res_len - left_len
pretty_line = sep * left_len + m + sep * right_len
print(pretty_line)
if args.D and args.D > 256:
args.run_torch_sdpa = True
pretty_print_line()
print(args)
pretty_print_line()
# Load the CUDA kernel as a python module
lib = load(
name="flash_attn_lib",
sources=get_build_sources(),
extra_cuda_cflags=get_build_cuda_cflags(),
extra_cflags=get_build_cflags(),
verbose=args.verbose,
)
if not args.build_others:
fake_fa_func = lambda q, k, v, o, s: o # fake FA func
setattr(lib, "flash_attn_mma_stages_split_q_shared_qkv_Os2g", fake_fa_func)
setattr(
lib, "flash_attn_mma_stages_split_q_shared_kv_acc_f32_rr", fake_fa_func
)
setattr(
lib, "flash_attn_mma_stages_split_q_shared_qkv_acc_f32_rr", fake_fa_func
)
def get_mha_tflops(
B: int, H: int, N: int, D: int, secs: float = 1.0, only_matmul: bool = False
):
# Q @ K^T FLOPs
flops_qk = B * H * N * N * (2 * D - 1)
# Scaling FLOPs
flops_scaling = B * H * N * N
# Safe_Softmax FLOPs
flops_row_max = B * H * N * (N - 1) # row max
flops_subtract_max = B * H * N * N # sub max
flops_exp = B * H * N * N # pointwise exp
flops_row_sum = B * H * N * (N - 1) # row sum
flops_normalization = B * H * N * N # normalization
flops_safe_softmax = (
flops_row_max
+ flops_subtract_max
+ flops_exp
+ flops_row_sum
+ flops_normalization
)
# P @ V FLOPs
flops_pv = B * H * N * D * (2 * N - 1)
# Total FLOPs
total_flops = flops_qk + flops_scaling + flops_safe_softmax + flops_pv
if only_matmul:
total_flops = flops_qk + flops_pv
# Convert to TFLOPS
# 1 TFLOPS = 10^12 FLOPS
# ref: https://imgtec.eetrend.com/blog/2021/100062210.html.
tflops = total_flops * 1e-12 / (secs)
return tflops
MAX_TFLOPS = -1
STATIS_INFO: dict[str, list[float]] = {}
TOATL_TFLOPS: dict[str, float] = {}
def run_benchmark(
perf_func: callable,
q: torch.Tensor,
k: torch.Tensor,
v: torch.Tensor,
tag: str,
out: Optional[torch.Tensor] = None,
s: Optional[torch.Tensor] = None, # DEBUG
stages: int = -1,
warmup: int = args.warmup,
iters: int = args.iters,
show_matrix: bool = args.show_matrix,
only_show_improved: bool = not args.show_all,
):
global MAX_TFLOPS
global MAX_HEADDIM_CFG
tag_hints: str = args.tag_hints # e.g "share-qkv,tiling-kv,swizzle"
if tag_hints:
tag_hints: list = tag_hints.strip().split(",")
tag_hints.append("flash")
tag_hints.append("sdpa")
tag_hints.append("unfused")
hit_hints = False
for hint in tag_hints:
if hint in tag:
hit_hints = True
if not hit_hints:
return None, None
if not args.build_others:
others_tags = ["s2g", "rr"]
for o_tag in others_tags:
if o_tag in tag:
return None, None
if "sdpa" in tag and (not args.run_torch_sdpa):
return None, None
if "unfused" in tag and (not args.run_torch_unfused):
return None, None
if "acc-f32" in tag and (not args.run_acc_f32):
return None, None
B, H, N, D = q.size()
if "flash" in tag:
B, N, H, D = q.size()
max_supported_D = MAX_HEADDIM_CFG.get(tag, None)
# skip if headdim not supported.
if max_supported_D is not None:
if D > max_supported_D:
return None, None
if out is not None:
out.fill_(0)
if s is not None:
s.fill_(0)
if out is not None:
for i in range(warmup):
if stages >= 1:
if s is not None:
perf_func(q, k, v, out, s, stages)
else:
perf_func(q, k, v, out, stages)
else:
perf_func(q, k, v, out)
else:
for i in range(warmup):
_ = perf_func(q, k, v)
torch.cuda.synchronize()
start = time.time()
# iters
if out is not None:
for i in range(iters):
if stages >= 1:
if s is not None:
perf_func(q, k, v, out, s, stages)
else:
perf_func(q, k, v, out, stages)
else:
perf_func(q, k, v, out)
else:
for i in range(iters):
out = perf_func(q, k, v)
torch.cuda.synchronize()
end = time.time()
total_secs = end - start
total_time = (end - start) * 1000 # ms
mean_time = total_time / iters
mean_secs = total_secs / iters
TFLOPS = get_mha_tflops(
B, H, N, D, mean_secs, only_matmul=args.only_flops_matmul
)
out_info = f"{tag}"
out_val_first = out.flatten()[:3].detach().cpu().numpy().tolist()
out_val_last = out.flatten()[-3:].detach().cpu().numpy().tolist()
out_val_first = [round(v, 8) for v in out_val_first]
out_val_last = [round(v, 8) for v in out_val_last]
out_val = out_val_first[:2]
out_val.append(out_val_last[-1])
out_val = [f"{v:<12}" for v in out_val]
# caculate TFLOPS improved.
if TFLOPS > MAX_TFLOPS:
if MAX_TFLOPS > 0:
improve = ((TFLOPS - MAX_TFLOPS) / MAX_TFLOPS) * 100
improve = round(improve, 2)
else:
improve = 0
MAX_TFLOPS = TFLOPS
print(
f"{out_info:>50}: {out_val}, time:{str(mean_time)[:8]}ms, "
f"TFLOPS:{TFLOPS:<6.2f}(+{improve:.2f}%)"
)
else:
if (not only_show_improved) or (("flash" in tag) or ("sdpa" in tag)):
print(
f"{out_info:>50}: {out_val}, time:{str(mean_time)[:8]}ms, "
f"TFLOPS:{TFLOPS:<6.2f}"
)
if show_matrix:
print(out)
time.sleep(args.sleep)
torch.cuda.synchronize()
return out.clone(), mean_time
def get_qkvo(B, H, N, D):
if not (args.no_rand_q or args.no_rand_qkv):
q = torch.randn((B, H, N, D), dtype=torch.half, device="cuda")
else:
q = torch.ones(B, H, N, D, device="cuda", dtype=torch.half).contiguous()
if not (args.no_rand_k or args.no_rand_qkv):
k = torch.randn((B, H, N, D), dtype=torch.half, device="cuda")
else:
k = torch.ones(B, H, N, D, device="cuda", dtype=torch.half).contiguous()
if args.range_k:
for i in range(N):
k[:, :, i, :] = (i + 1) / N
k = k.cuda().half().contiguous()
if not (args.no_rand_v or args.no_rand_qkv):
v = torch.randn((B, H, N, D), dtype=torch.half, device="cuda")
else:
v = torch.ones(B, H, N, D, device="cuda", dtype=torch.half).contiguous()
o = torch.zeros(B, H, N, D, device="cuda", dtype=torch.half).contiguous()
# transpose (H,N) -> (N,H) for FA2.
fq = q.transpose(1, 2).contiguous()
fk = k.transpose(1, 2).contiguous()
fv = v.transpose(1, 2).contiguous()
# transpose (N,D) -> (D,N) for V smem swizzle.
tk = k.transpose(-2, -1).contiguous() # [B,H,N,D] -> [B,H,D,N]
tv = v.transpose(-2, -1).contiguous() # [B,H,N,D] -> [B,H,D,N]
return q, k, v, o, fq, fk, fv, tk, tv
# un-fused naive attn
def unfused_standard_attn(q: torch.Tensor, k: torch.Tensor, v: torch.Tensor):
att = q @ k.transpose(-2, -1) * (1.0 / math.sqrt(k.size(-1)))
att = F.softmax(att, dim=-1)
y = att @ v
return y
def sdpa(q: Tensor, k: Tensor, v: Tensor, use_flash: bool = False):
if not use_flash:
with sdpa_kernel(SDPBackend.EFFICIENT_ATTENTION):
out: Tensor = F.scaled_dot_product_attention(q, k, v)
else:
with sdpa_kernel(SDPBackend.FLASH_ATTENTION):
out: Tensor = F.scaled_dot_product_attention(q, k, v)
return out
def check_all_close(
out_flash_or_sdpa: torch.Tensor,
out_mma: torch.Tensor,
tag: str = "out_mma",
check_all: bool = False,
is_flash: bool = True,
):
if any((out_flash_or_sdpa is None, out_mma is None)):
return
if is_flash:
true_tag = "out_flash"
out_flash_or_sdpa = out_flash_or_sdpa.transpose(1, 2)
else:
true_tag = "out_sdpa"
if check_all:
for i in range(int(N / 8)):
if i < 4:
pretty_print_line()
print(f"{true_tag}[:, :, {(i*8)}:{(i+1)*8}, :]:\n")
print(out_flash_or_sdpa[:, :, (i * 8) : (i + 1) * 8, :].float())
print(f"{tag}[:, :, {(i*8)}:{(i+1)*8}, :]:\n")
print(out_mma[:, :, (i * 8) : (i + 1) * 8, :].float())
pretty_print_line()
diff = torch.abs(out_flash_or_sdpa - out_mma)
all_close = str(torch.allclose(out_flash_or_sdpa, out_mma, atol=1e-2))
pretty_print_line(
f"{true_tag} vs {tag:<25}, all close: {all_close:<6}, "
f"max diff: {diff.max().item():.6f}, min diff: {diff.min().item():.6f}, "
f"mean diff: {diff.mean().item():.6f}"
)
Bs = [1, 4, 8] if not args.B else [args.B]
Hs = [1, 4, 8] if not args.H else [args.H]
Ns = [1024, 2048, 4096, 8192] if not args.N else [args.N]
Ds = [64, 128, 256, 512] if not args.D else [args.D]
# batch_size, n_head, seq_len, head_dim (B,H,N,D)
BHNDs = [(B, H, N, D) for B in Bs for H in Hs for N in Ns for D in Ds]
# max headdim supported for different methods. skip if D > max_D.
MAX_HEADDIM_CFG: dict[str, int] = {
# FA2, SDPA, Naive MHA.
"(flash)": 256,
"(sdpa)": 4096, # may no limit
"(unfused)": 4096, # may no limit
# Split-KV
"mma(split-kv+stage1)": 128,
"mma(split-kv+stage2)": 128,
# Split-Q
"mma(split-q+stage1)": 128,
"mma(split-q+stage2)": 128,
# Split-Q + Shared KV SMEM
"mma(split-q+share-kv+stage1)": 256,
"mma(split-q+share-kv+stage2)": 128,
"mma(split-q+share-kv+swizzle-q+stage1)": 256,
"mma(split-q+share-kv+swizzle-q+stage2)": 128,
"mma(split-q+share-kv+swizzle-qk+stage1)": 256,
"mma(split-q+share-kv+swizzle-qk+stage2)": 128,
"mma(split-q+share-kv+swizzle-qkv+stage1)": 256,
"mma(split-q+share-kv+swizzle-qkv+stage2)": 128,
"mma(split-q+share-kv+acc-f32+stage1)": 256,
"mma(split-q+share-kv+acc-f32+stage2)": 128,
# Split-Q + Fully Shared QKV SMEM
"mma(split-q+share-qkv+stage1)": 256,
"mma(split-q+share-qkv+stage2)": 128,
"mma(split-q+share-qkv+swizzle-q+stage1)": 256,
"mma(split-q+share-qkv+swizzle-q+stage2)": 128,
"mma(split-q+share-qkv+swizzle-qk+stage1)": 256,
"mma(split-q+share-qkv+swizzle-qk+stage2)": 128,
"mma(split-q+share-qkv+swizzle-qkv+stage1)": 256,
"mma(split-q+share-qkv+swizzle-qkv+stage2)": 128,
"mma(split-q+share-qkv+acc-f32+stage1)": 256,
"mma(split-q+share-qkv+acc-f32+stage2)": 128,
# Split-Q + QK Fine-grained Tiling
"mma(split-q+tiling-qk+stage1)": 1024,
"mma(split-q+tiling-qk+stage2)": 1024,
"mma(split-q+tiling-qk+swizzle-q+stage1)": 1024,
"mma(split-q+tiling-qk+swizzle-q+stage2)": 1024,
"mma(split-q+tiling-qk+swizzle-qk+stage1)": 1024,
"mma(split-q+tiling-qk+swizzle-qk+stage2)": 1024,
"mma(split-q+tiling-qk+swizzle-qkv+stage1)": 256,
"mma(split-q+tiling-qk+swizzle-qkv+stage2)": 256,
"mma(split-q+tiling-qk+acc-f32+stage1)": 1024,
"mma(split-q+tiling-qk+acc-f32+stage2)": 1024,
# Split-Q + Fully QKV Fine-grained Tiling
"mma(split-q+tiling-qkv+stage1)": 1024,
"mma(split-q+tiling-qkv+stage2)": 1024,
"mma(split-q+tiling-qkv+acc-f32+stage1)": 1024,
"mma(split-q+tiling-qkv+acc-f32+stage2)": 1024,
"mma(split-q+tiling-qkv+swizzle-q+stage1)": 1024,
"mma(split-q+tiling-qkv+swizzle-q+stage2)": 1024,
"mma(split-q+tiling-qkv+swizzle-qk+stage1)": 1024,
"mma(split-q+tiling-qkv+swizzle-qk+stage2)": 1024,
"mma(split-q+tiling-qkv+swizzle-qkv+stage1)": 1024,
"mma(split-q+tiling-qkv+swizzle-qkv+stage2)": 1024,
"mma(split-q+tiling-qkv+acc-f32+swizzle-q+stage1)": 1024,
"mma(split-q+tiling-qkv+acc-f32+swizzle-q+stage2)": 1024,
"mma(split-q+tiling-qkv+acc-f32+swizzle-qk+stage1)": 1024,
"mma(split-q+tiling-qkv+acc-f32+swizzle-qk+stage2)": 1024,
"mma(split-q+tiling-qkv+acc-f32+swizzle-qkv+stage1)": 1024,
"mma(split-q+tiling-qkv+acc-f32+swizzle-qkv+stage2)": 1024,
# Others, O s2g, etc.
"mma(split-q+share-qkv+o-s2g+stage1)": 256,
"mma(split-q+share-qkv+o-s2g+stage2)": 128,
"mma(split-q+share-kv+acc-f32+rr+stage1)": 256,
"mma(split-q+share-kv+acc-f32+rr+stage2)": 128,
"mma(split-q+share-qkv+acc-f32+rr+stage1)": 256,
"mma(split-q+share-qkv+acc-f32+rr+stage2)": 256,
"mma(split-q+tiling-qk+acc-f32+rr+stage1)": 1024,
"mma(split-q+tiling-qk+acc-f32+rr+stage2)": 1024,
}
seed = args.seed if args.seed else random.choice(range(10000))
set_rand_seed(seed)
pretty_print_line()
pretty_print_line(
f"B: batch_size, H: n_head, N: seq_len, D: head_dim, "
f"seed: {seed}, Warmup: {args.warmup}, Iters: {args.iters}"
)
run_torch_sdpa = args.run_torch_sdpa
for B, H, N, D in BHNDs:
MAX_TFLOPS = -1
q, k, v, o, fq, fk, fv, tk, tv = get_qkvo(B, H, N, D)
if D > 256:
args.run_torch_sdpa = True
else:
args.run_torch_sdpa = run_torch_sdpa
torch.cuda.synchronize()
pretty_print_line()
pretty_print_line(
f"B={B}, H={H}, N={N}, D={D}, Warmup: {args.warmup}, Iters: {args.iters}"
)
# Naive MHA.
out_unfused, _ = run_benchmark(unfused_standard_attn, q, k, v, "(unfused)")
# Split-KV
out_mma_split_kv1, _ = run_benchmark(
lib.flash_attn_mma_stages_split_kv,
q,
k,
v,
"mma(split-kv+stage1)",
o,
stages=1,
)
out_mma_split_kv2, _ = run_benchmark(
lib.flash_attn_mma_stages_split_kv,
q,
k,
v,
"mma(split-kv+stage2)",
o,
stages=2,
)
# Split-Q
out_mma_split_q1, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q,
q,
k,
v,
"mma(split-q+stage1)",
o,
stages=1,
)
out_mma_split_q2, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q,
q,
k,
v,
"mma(split-q+stage2)",
o,
stages=2,
)
# Split-Q + Shared KV SMEM + Swizzle
out_mma_share_kv1, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_shared_kv,
q,
k,
v,
"mma(split-q+share-kv+stage1)",
o,
stages=1,
)
out_mma_share_kv2, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_shared_kv,
q,
k,
v,
"mma(split-q+share-kv+stage2)",
o,
stages=2,
)
out_mma_share_kv_f321, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_shared_kv_acc_f32,
q,
k,
v,
"mma(split-q+share-kv+acc-f32+stage1)",
o,
stages=1,
)
out_mma_share_kv_f322, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_shared_kv_acc_f32,
q,
k,
v,
"mma(split-q+share-kv+acc-f32+stage2)",
o,
stages=2,
)
out_mma_share_kv_sq1, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_shared_kv_swizzle_q,
q,
k,
v,
"mma(split-q+share-kv+swizzle-q+stage1)",
o,
stages=1,
)
out_mma_share_kv_sq2, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_shared_kv_swizzle_q,
q,
k,
v,
"mma(split-q+share-kv+swizzle-q+stage2)",
o,
stages=2,
)
out_mma_share_kv_sqk1, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_shared_kv_swizzle_qk,
q,
k,
v,
"mma(split-q+share-kv+swizzle-qk+stage1)",
o,
stages=1,
)
out_mma_share_kv_sqk2, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_shared_kv_swizzle_qk,
q,
k,
v,
"mma(split-q+share-kv+swizzle-qk+stage2)",
o,
stages=2,
)
out_mma_share_kv_sqkv1, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_shared_kv_swizzle_qkv,
q,
k,
tv,
"mma(split-q+share-kv+swizzle-qkv+stage1)",
o,
stages=1,
)
out_mma_share_kv_sqkv2, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_shared_kv_swizzle_qkv,
q,
k,
tv,
"mma(split-q+share-kv+swizzle-qkv+stage2)",
o,
stages=2,
)
# Split-Q + Fully Shared QKV SMEM + Swizzle
out_mma_share_qkv1, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_shared_qkv,
q,
k,
v,
"mma(split-q+share-qkv+stage1)",
o,
stages=1,
)
out_mma_share_qkv2, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_shared_qkv,
q,
k,
v,
"mma(split-q+share-qkv+stage2)",
o,
stages=2,
)
out_mma_share_qkv_f321, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_shared_qkv_acc_f32,
q,
k,
v,
"mma(split-q+share-qkv+acc-f32+stage1)",
o,
stages=1,
)
out_mma_share_qkv_f322, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_shared_qkv_acc_f32,
q,
k,
v,
"mma(split-q+share-qkv+acc-f32+stage2)",
o,
stages=2,
)
out_mma_share_qkv_sq1, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_shared_qkv_swizzle_q,
q,
k,
v,
"mma(split-q+share-qkv+swizzle-q+stage1)",
o,
stages=1,
)
out_mma_share_qkv_sq2, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_shared_qkv_swizzle_q,
q,
k,
v,
"mma(split-q+share-qkv+swizzle-q+stage2)",
o,
stages=2,
)
out_mma_share_qkv_sqk1, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_shared_qkv_swizzle_qk,
q,
k,
v,
"mma(split-q+share-qkv+swizzle-qk+stage1)",
o,
stages=1,
)
out_mma_share_qkv_sqk2, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_shared_qkv_swizzle_qk,
q,
k,
v,
"mma(split-q+share-qkv+swizzle-qk+stage2)",
o,
stages=2,
)
out_mma_share_qkv_sqkv1, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_shared_qkv_swizzle_qkv,
q,
k,
tv,
"mma(split-q+share-qkv+swizzle-qkv+stage1)",
o,
stages=1,
)
out_mma_share_qkv_sqkv2, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_shared_qkv_swizzle_qkv,
q,
k,
tv,
"mma(split-q+share-qkv+swizzle-qkv+stage2)",
o,
stages=2,
)
# Split-Q + QK Fine-grained Tiling + Swizzle
out_mma_tiling_qk1, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_tiling_qk,
q,
k,
v,
"mma(split-q+tiling-qk+stage1)",
o,
stages=1,
)
out_mma_tiling_qk2, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_tiling_qk,
q,
k,
v,
"mma(split-q+tiling-qk+stage2)",
o,
stages=2,
)
out_mma_tiling_qk_f321, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_tiling_qk_acc_f32,
q,
k,
v,
"mma(split-q+tiling-qk+acc-f32+stage1)",
o,
stages=1,
)
out_mma_tiling_qk_f322, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_tiling_qk_acc_f32,
q,
k,
v,
"mma(split-q+tiling-qk+acc-f32+stage2)",
o,
stages=2,
)
out_mma_tiling_qk_sq1, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_tiling_qk_swizzle_q,
q,
k,
v,
"mma(split-q+tiling-qk+swizzle-q+stage1)",
o,
stages=1,
)
out_mma_tiling_qk_sq2, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_tiling_qk_swizzle_q,
q,
k,
v,
"mma(split-q+tiling-qk+swizzle-q+stage2)",
o,
stages=2,
)
out_mma_tiling_qk_sqk1, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_tiling_qk_swizzle_qk,
q,
k,
v,
"mma(split-q+tiling-qk+swizzle-qk+stage1)",
o,
stages=1,
)
out_mma_tiling_qk_sqk2, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_tiling_qk_swizzle_qk,
q,
k,
v,
"mma(split-q+tiling-qk+swizzle-qk+stage2)",
o,
stages=2,
)
out_mma_tiling_qk_sqkv1, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_tiling_qk_swizzle_qkv,
q,
k,
tv,
"mma(split-q+tiling-qk+swizzle-qkv+stage1)",
o,
stages=1,
)
out_mma_tiling_qk_sqkv2, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_tiling_qk_swizzle_qkv,
q,
k,
tv,
"mma(split-q+tiling-qk+swizzle-qkv+stage2)",
o,
stages=2,
)
# Split-Q + QKV Fully Fine-grained Tiling
out_mma_tiling_qkv1, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_tiling_qkv,
q,
k,
v,
"mma(split-q+tiling-qkv+stage1)",
o,
stages=1,
)
out_mma_tiling_qkv2, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_tiling_qkv,
q,
k,
v,
"mma(split-q+tiling-qkv+stage2)",
o,
stages=2,
)
out_mma_tiling_qkv_sq1, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_tiling_qkv_swizzle_q,
q,
k,
v,
"mma(split-q+tiling-qkv+swizzle-q+stage1)",
o,
stages=1,
)
out_mma_tiling_qkv_sq2, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_tiling_qkv_swizzle_q,
q,
k,
v,
"mma(split-q+tiling-qkv+swizzle-q+stage2)",
o,
stages=2,
)
out_mma_tiling_qkv_sqk1, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_tiling_qkv_swizzle_qk,
q,
k,
v,
"mma(split-q+tiling-qkv+swizzle-qk+stage1)",
o,
stages=1,
)
out_mma_tiling_qkv_sqk2, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_tiling_qkv_swizzle_qk,
q,
k,
v,
"mma(split-q+tiling-qkv+swizzle-qk+stage2)",
o,
stages=2,
)
out_mma_tiling_qkv_sqkv1, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_tiling_qkv_swizzle_qkv,
q,
k,
v,
"mma(split-q+tiling-qkv+swizzle-qkv+stage1)",
o,
stages=1,
)
out_mma_tiling_qkv_sqkv2, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_tiling_qkv_swizzle_qkv,
q,
k,
v,
"mma(split-q+tiling-qkv+swizzle-qkv+stage2)",
o,
stages=2,
)
out_mma_tiling_qkv_f321, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_tiling_qkv_acc_f32,
q,
k,
v,
"mma(split-q+tiling-qkv+acc-f32+stage1)",
o,
stages=1,
)
out_mma_tiling_qkv_f322, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_tiling_qkv_acc_f32,
q,
k,
v,
"mma(split-q+tiling-qkv+acc-f32+stage2)",
o,
stages=2,
)
out_mma_tiling_qkv_fsq1, _ = run_benchmark(
lib.flash_attn_mma_stages_split_q_tiling_qkv_acc_f32_swizzle_q,