Files
AstrAI/tests/extension/test_gemv.py
T
0z5a d4a292b36b perf: tune bf16 gemv and add opt-in fused swiglu
- deepen common-shape BF16 GEMV tuning with warp-row tiling for LLaMA/Qwen2/GPT-NeoX/OPT decode projections
- add fused BF16 up/gate SwiGLU CUDA primitive with ASTRAI_SWIGLU=0/1/auto dispatch
- keep the unfused linear backend as the default path; auto enables no shape until per-architecture checkpoint gates pass
- fall back to the linear/torch chain when kernels are absent, on CPU, in training, or outside supported M/K/dtype shapes
- add gemv/swiglu benchmark scripts, dispatch and parity tests, and kernel documentation

Benchmark: NVIDIA L20 (sm_89), CUDA 12.8, PyTorch 2.11.0+cu128, idle GPU. AstrAI 1B config (24 layers, hidden 1536, vocab 100000), BF16, prompt 128, 32 greedy decode tokens, CUDA graphs enabled, A/B in separate interleaved processes (3 rounds, 8 trials each, medians). Default vs ASTRAI_SWIGLU=1 per generate call: batch 1 134.8->129.1 ms (+4.44%), batch 2 136.2->130.9 ms (+4.06%), batch 4 145.5->140.3 ms (+3.66%). Greedy output identical at batch 1, differs at batch 2/4, so auto stays unfused by default; kernelless fallback verified bit-identical greedy.
2026-09-03 04:26:53 +08:00

224 lines
6.9 KiB
Python

import pytest
import torch
import torch.nn.functional as F
from astrai.extension import bf16_gemv, is_available
GEMV_AVAILABLE = (
torch.cuda.is_available()
and is_available("bf16_gemv")
and torch.cuda.get_device_capability() >= (8, 0)
)
skip_no_gemv = pytest.mark.skipif(
not GEMV_AVAILABLE,
reason="BF16 GEMV requires a built kernel and compute capability 8.0+",
)
@skip_no_gemv
@pytest.mark.parametrize(
"n,k",
[(256, 1536), (1536, 1536), (6912, 1536), (1536, 6912), (100000, 1536)],
)
def test_bf16_gemv_matches_linear_shape_families(n, k):
torch.manual_seed(17)
x = torch.randn(k, device="cuda", dtype=torch.bfloat16)
weight = torch.randn(n, k, device="cuda", dtype=torch.bfloat16)
actual = bf16_gemv(x, weight)
expected = F.linear(x, weight)
assert actual.shape == (n,)
torch.testing.assert_close(actual, expected, rtol=0.02, atol=0.25)
@skip_no_gemv
@pytest.mark.parametrize("m", [2, 3, 4, 5, 6, 7, 8])
@pytest.mark.parametrize("n,k", [(256, 1536), (1536, 1536), (1536, 6912)])
def test_bf16_gemv_matches_small_decode_batches(m, n, k):
torch.manual_seed(19 + m)
x = torch.randn(m, k, device="cuda", dtype=torch.bfloat16)
weight = torch.randn(n, k, device="cuda", dtype=torch.bfloat16)
actual = bf16_gemv(x, weight)
expected = F.linear(x, weight)
assert actual.shape == (m, n)
torch.testing.assert_close(actual, expected, rtol=0.02, atol=0.5)
@skip_no_gemv
@pytest.mark.parametrize("m", [2, 4])
@pytest.mark.parametrize(
"n,k",
[
(1024, 4096),
(4096, 4096),
(11008, 4096),
(4096, 11008),
(14336, 4096),
(4096, 14336),
(5120, 5120),
(13824, 5120),
(5120, 13824),
(16384, 4096),
(4096, 16384),
(512, 3584),
(3584, 3584),
(18944, 3584),
(3584, 18944),
(1024, 8192),
(8192, 8192),
(28672, 8192),
(8192, 28672),
(2048, 2048),
(8192, 2048),
(2048, 8192),
],
)
def test_bf16_gemv_matches_common_transformer_shapes(m, n, k):
torch.manual_seed(2026 + m + n + k)
x = torch.randn(m, k, device="cuda", dtype=torch.bfloat16)
weight = torch.empty(n, k, device="cuda", dtype=torch.bfloat16)
weight.normal_(mean=0.0, std=0.02)
actual = bf16_gemv(x, weight)
expected = F.linear(x, weight)
torch.testing.assert_close(actual, expected, rtol=0.02, atol=0.25)
@skip_no_gemv
@pytest.mark.parametrize(
"m,n,k",
[
(1, 8192, 2048),
(8, 4096, 11008),
(8, 512, 3584),
(8, 1024, 8192),
(8, 2048, 8192),
],
)
def test_bf16_gemv_matches_half_cta_edge_bands(m, n, k):
torch.manual_seed(2026 + m + n + k)
x = torch.randn(m, k, device="cuda", dtype=torch.bfloat16)
weight = torch.empty(n, k, device="cuda", dtype=torch.bfloat16)
weight.normal_(mean=0.0, std=0.02)
actual = bf16_gemv(x, weight)
expected = F.linear(x, weight)
torch.testing.assert_close(actual, expected, rtol=0.02, atol=0.25)
@skip_no_gemv
def test_bf16_gemv_preserves_singleton_batch_and_fuses_bias():
torch.manual_seed(23)
x = torch.randn(1, 1536, device="cuda", dtype=torch.bfloat16)
weight = torch.randn(1536, 1536, device="cuda", dtype=torch.bfloat16)
bias = torch.randn(1536, device="cuda", dtype=torch.bfloat16)
actual = bf16_gemv(x, weight, bias)
expected = F.linear(x, weight, bias)
assert actual.shape == (1, 1536)
torch.testing.assert_close(actual, expected, rtol=0.02, atol=0.25)
@skip_no_gemv
def test_bf16_gemv_small_batch_fuses_bias():
torch.manual_seed(25)
x = torch.randn(4, 1536, device="cuda", dtype=torch.bfloat16)
weight = torch.randn(256, 1536, device="cuda", dtype=torch.bfloat16)
bias = torch.randn(256, device="cuda", dtype=torch.bfloat16)
actual = bf16_gemv(x, weight, bias)
expected = F.linear(x, weight, bias)
torch.testing.assert_close(actual, expected, rtol=0.02, atol=0.25)
@skip_no_gemv
def test_bf16_gemv_uses_current_stream():
x = torch.randn(1536, device="cuda", dtype=torch.bfloat16)
weight = torch.randn(256, 1536, device="cuda", dtype=torch.bfloat16)
stream = torch.cuda.Stream()
with torch.cuda.stream(stream):
actual = bf16_gemv(x, weight)
expected = F.linear(x, weight)
stream.synchronize()
torch.testing.assert_close(actual, expected, rtol=0.02, atol=0.25)
@skip_no_gemv
def test_bf16_gemv_cuda_graph_replay():
torch.manual_seed(29)
x = torch.randn(1536, device="cuda", dtype=torch.bfloat16)
weight = torch.randn(1536, 1536, device="cuda", dtype=torch.bfloat16)
for _ in range(3):
bf16_gemv(x, weight)
graph = torch.cuda.CUDAGraph()
with torch.cuda.graph(graph):
actual = bf16_gemv(x, weight)
x.copy_(torch.randn_like(x))
graph.replay()
expected = F.linear(x, weight)
torch.testing.assert_close(actual, expected, rtol=0.02, atol=0.25)
@skip_no_gemv
@pytest.mark.parametrize("n,k", [(64, 7), (64, 12), (33, 100), (256, 1534)])
def test_bf16_gemv_handles_unaligned_k(n, k):
torch.manual_seed(29)
x = torch.randn(k, device="cuda", dtype=torch.bfloat16)
weight = torch.randn(n, k, device="cuda", dtype=torch.bfloat16)
actual = bf16_gemv(x, weight)
expected = F.linear(x, weight)
torch.testing.assert_close(actual, expected, rtol=0.02, atol=0.25)
x3 = torch.randn(3, k, device="cuda", dtype=torch.bfloat16)
actual3 = bf16_gemv(x3, weight)
torch.testing.assert_close(actual3, F.linear(x3, weight), rtol=0.02, atol=0.5)
@skip_no_gemv
def test_bf16_gemv_small_batch_cuda_graph_replay():
torch.manual_seed(31)
x = torch.randn(8, 1536, device="cuda", dtype=torch.bfloat16)
weight = torch.randn(1536, 1536, device="cuda", dtype=torch.bfloat16)
for _ in range(3):
bf16_gemv(x, weight)
graph = torch.cuda.CUDAGraph()
with torch.cuda.graph(graph):
actual = bf16_gemv(x, weight)
x.copy_(torch.randn_like(x))
graph.replay()
expected = F.linear(x, weight)
torch.testing.assert_close(actual, expected, rtol=0.02, atol=0.25)
@skip_no_gemv
@pytest.mark.parametrize(
"make_args,error",
[
(
lambda: (
torch.randn(9, 16, device="cuda", dtype=torch.bfloat16),
torch.randn(8, 16, device="cuda", dtype=torch.bfloat16),
),
"M must",
),
(
lambda: (
torch.randn(16, device="cuda", dtype=torch.float16),
torch.randn(8, 16, device="cuda", dtype=torch.float16),
),
"bf16",
),
(
lambda: (
torch.randn(
16, device="cuda", dtype=torch.bfloat16, requires_grad=True
),
torch.randn(8, 16, device="cuda", dtype=torch.bfloat16),
),
"autograd",
),
],
)
def test_bf16_gemv_rejects_unsupported_inputs(make_args, error):
with pytest.raises(RuntimeError, match=error):
bf16_gemv(*make_args())