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AstrAI/csrc/bench/benchmark_gemv.py
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ViperEkura 28d11f1610 chore: relocate kernel benchmarks to csrc/bench
- Move benchmark_gemv.py, benchmark_swiglu.py, and benchmark_gemv_common.py from scripts/tools/ to csrc/bench/ so kernel benchmarks live next to the kernels they measure
- Update reproduction commands in decode_linear_benchmark.md, swiglu_benchmark.md, and cuda_kernels.md
- Codify the placement convention in AGENTS.md: kernel benchmarks in csrc/bench/, pure-CUDA harnesses in csrc/tests/*.cu, engine and evaluation benchmarks in scripts/
2026-09-03 21:06:33 +08:00

334 lines
10 KiB
Python

"""Benchmark decode-time linear shapes before enabling custom GEMV dispatch.
The benchmark deliberately calls ``torch.nn.functional.linear`` directly. It
establishes the per-architecture cuBLAS baseline that later GEMV primitives and
dispatch decisions must beat.
"""
from __future__ import annotations
import json
import math
import statistics
from dataclasses import asdict, dataclass
from datetime import datetime, timezone
from pathlib import Path
from typing import Callable, Iterable
import click
import torch
import torch.nn.functional as F
@dataclass(frozen=True)
class LinearShape:
name: str
n: int
k: int
DEFAULT_SHAPES = (
LinearShape("q_proj", 1536, 1536),
LinearShape("k_proj", 256, 1536),
LinearShape("v_proj", 256, 1536),
LinearShape("attn_out", 1536, 1536),
LinearShape("mlp_up", 6912, 1536),
LinearShape("mlp_gate", 6912, 1536),
LinearShape("mlp_down", 1536, 6912),
LinearShape("lm_head", 100000, 1536),
)
DTYPES = {"bfloat16": torch.bfloat16, "float16": torch.float16}
def parse_positive_ints(value: str) -> tuple[int, ...]:
"""Parse a comma-separated, duplicate-free list of positive integers."""
try:
values = tuple(dict.fromkeys(int(item.strip()) for item in value.split(",")))
except ValueError as exc:
raise click.BadParameter("expected comma-separated integers") from exc
if not values or any(item <= 0 for item in values):
raise click.BadParameter("values must be positive integers")
return values
def parse_shape(value: str) -> LinearShape:
"""Parse NAME:N:K into a benchmark shape."""
parts = value.split(":")
if len(parts) != 3 or not parts[0]:
raise click.BadParameter("shape must use NAME:N:K")
try:
n, k = (int(item) for item in parts[1:])
except ValueError as exc:
raise click.BadParameter("N and K must be integers") from exc
if n <= 0 or k <= 0:
raise click.BadParameter("N and K must be positive")
return LinearShape(parts[0], n, k)
def estimate_io_bytes(
m: int, n: int, k: int, element_size: int, *, has_bias: bool
) -> int:
"""Estimate bytes touched once by Y[M,N] = X[M,K] @ W[N,K].T."""
elements = m * k + n * k + m * n
if has_bias:
elements += n
return elements * element_size
def percentile(values: Iterable[float], quantile: float) -> float:
ordered = sorted(values)
if not ordered:
raise ValueError("percentile requires at least one sample")
rank = (len(ordered) - 1) * quantile
lower = math.floor(rank)
upper = math.ceil(rank)
if lower == upper:
return ordered[lower]
fraction = rank - lower
return ordered[lower] * (1 - fraction) + ordered[upper] * fraction
def summarize_latency(samples_ms: list[float]) -> dict[str, float]:
return {
"median_ms": statistics.median(samples_ms),
"p90_ms": percentile(samples_ms, 0.90),
"p99_ms": percentile(samples_ms, 0.99),
"min_ms": min(samples_ms),
"max_ms": max(samples_ms),
}
def measure_cuda_ms(
operation: Callable[[], torch.Tensor], *, warmup: int, iterations: int, trials: int
) -> list[float]:
for _ in range(warmup):
operation()
torch.cuda.synchronize()
samples = []
for _ in range(trials):
start = torch.cuda.Event(enable_timing=True)
end = torch.cuda.Event(enable_timing=True)
start.record()
for _ in range(iterations):
operation()
end.record()
end.synchronize()
samples.append(start.elapsed_time(end) / iterations)
return samples
def count_cuda_kernels(
operation: Callable[[], torch.Tensor], repeats: int = 5
) -> float:
"""Profile a few calls and return the average device events per call."""
with torch.profiler.profile(
activities=[
torch.profiler.ProfilerActivity.CPU,
torch.profiler.ProfilerActivity.CUDA,
],
acc_events=True,
) as profile:
for _ in range(repeats):
operation()
torch.cuda.synchronize()
device_type = torch.autograd.DeviceType.CUDA
events = [event for event in profile.events() if event.device_type == device_type]
return len(events) / repeats
def capture_linear(
x: torch.Tensor, weight: torch.Tensor, bias: torch.Tensor | None
) -> tuple[torch.cuda.CUDAGraph, torch.Tensor]:
for _ in range(3):
F.linear(x, weight, bias)
torch.cuda.synchronize()
graph = torch.cuda.CUDAGraph()
with torch.cuda.graph(graph):
output = F.linear(x, weight, bias)
return graph, output
def benchmark_case(
shape: LinearShape,
m: int,
*,
dtype: torch.dtype,
mode: str,
bias_enabled: bool,
warmup: int,
iterations: int,
trials: int,
) -> dict[str, object]:
x = torch.randn((m, shape.k), device="cuda", dtype=dtype)
weight = torch.randn((shape.n, shape.k), device="cuda", dtype=dtype)
bias = torch.randn(shape.n, device="cuda", dtype=dtype) if bias_enabled else None
graph = None
graph_output = None
if mode == "graph":
graph, graph_output = capture_linear(x, weight, bias)
def operation() -> torch.Tensor:
graph.replay()
return graph_output
else:
def operation() -> torch.Tensor:
return F.linear(x, weight, bias)
samples_ms = measure_cuda_ms(
operation, warmup=warmup, iterations=iterations, trials=trials
)
latency = summarize_latency(samples_ms)
io_bytes = estimate_io_bytes(
m, shape.n, shape.k, x.element_size(), has_bias=bias is not None
)
median_seconds = latency["median_ms"] / 1000
result: dict[str, object] = {
"name": shape.name,
"m": m,
"n": shape.n,
"k": shape.k,
"mode": mode,
"bias": bias is not None,
"estimated_io_bytes": io_bytes,
"effective_bandwidth_gbps": io_bytes / median_seconds / 1e9,
"cuda_kernel_launches_per_call": count_cuda_kernels(operation),
**latency,
"samples_ms": samples_ms,
}
return result
def render_markdown(payload: dict[str, object]) -> str:
metadata = payload["metadata"]
assert isinstance(metadata, dict)
results = payload["results"]
assert isinstance(results, list)
lines = [
"# Decode linear baseline",
"",
f"- GPU: {metadata['gpu_name']}",
f"- Compute capability: {metadata['compute_capability']}",
f"- PyTorch / CUDA: {metadata['torch_version']} / {metadata['cuda_version']}",
f"- Dtype: {metadata['dtype']}",
"",
"| Layer | M | N | K | Mode | Median (ms) | p99 (ms) | GB/s | CUDA kernels/call |",
"|---|---:|---:|---:|---|---:|---:|---:|---:|",
]
for item in results:
assert isinstance(item, dict)
lines.append(
"| {name} | {m} | {n} | {k} | {mode} | {median_ms:.4f} | "
"{p99_ms:.4f} | {effective_bandwidth_gbps:.1f} | "
"{cuda_kernel_launches_per_call:.2f} |".format(**item)
)
lines.append("")
return "\n".join(lines)
def device_metadata(dtype_name: str) -> dict[str, object]:
props = torch.cuda.get_device_properties(0)
return {
"timestamp_utc": datetime.now(timezone.utc).isoformat(),
"gpu_name": props.name,
"compute_capability": f"{props.major}.{props.minor}",
"total_memory_bytes": props.total_memory,
"torch_version": torch.__version__,
"cuda_version": torch.version.cuda,
"dtype": dtype_name,
}
@click.command(help=__doc__)
@click.option("--output", type=click.Path(path_type=Path), required=True)
@click.option("--markdown-output", type=click.Path(path_type=Path))
@click.option("--m-values", default="1,2,4,8,16,32", show_default=True)
@click.option(
"--shape",
"shape_values",
multiple=True,
help="Override defaults with repeatable NAME:N:K shapes.",
)
@click.option("--dtype", type=click.Choice(tuple(DTYPES)), default="bfloat16")
@click.option("--mode", type=click.Choice(("eager", "graph", "both")), default="both")
@click.option("--bias/--no-bias", default=False)
@click.option("--warmup", type=click.IntRange(min=1), default=10, show_default=True)
@click.option(
"--iterations", type=click.IntRange(min=1), default=100, show_default=True
)
@click.option("--trials", type=click.IntRange(min=1), default=20, show_default=True)
@click.option("--seed", type=int, default=0, show_default=True)
def benchmark_command(
output: Path,
markdown_output: Path | None,
m_values: str,
shape_values: tuple[str, ...],
dtype: str,
mode: str,
bias: bool,
warmup: int,
iterations: int,
trials: int,
seed: int,
) -> None:
if not torch.cuda.is_available():
raise click.ClickException("CUDA is required")
parsed_m = parse_positive_ints(m_values)
shapes = tuple(parse_shape(item) for item in shape_values) or DEFAULT_SHAPES
modes = ("eager", "graph") if mode == "both" else (mode,)
torch.manual_seed(seed)
torch.cuda.manual_seed_all(seed)
results = []
for shape in shapes:
for m in parsed_m:
for current_mode in modes:
click.echo(
f"{shape.name}: M={m} N={shape.n} K={shape.k} {current_mode}"
)
results.append(
benchmark_case(
shape,
m,
dtype=DTYPES[dtype],
mode=current_mode,
bias_enabled=bias,
warmup=warmup,
iterations=iterations,
trials=trials,
)
)
payload: dict[str, object] = {
"schema_version": 1,
"metadata": device_metadata(dtype),
"parameters": {
"m_values": list(parsed_m),
"shapes": [asdict(shape) for shape in shapes],
"modes": list(modes),
"bias": bias,
"warmup": warmup,
"iterations": iterations,
"trials": trials,
"seed": seed,
},
"results": results,
}
output.parent.mkdir(parents=True, exist_ok=True)
output.write_text(json.dumps(payload, indent=2) + "\n", encoding="utf-8")
if markdown_output is not None:
markdown_output.parent.mkdir(parents=True, exist_ok=True)
markdown_output.write_text(render_markdown(payload), encoding="utf-8")
if __name__ == "__main__":
benchmark_command()