Files
AstrAI/docs/developer/decode_linear_benchmark.md
T
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

2.1 KiB

Decode linear shape benchmark

csrc/bench/benchmark_gemv.py records the F.linear baseline used to decide whether a BF16 GEMV or small-M kernel should enter automatic inference dispatch. It does not change model execution or select a custom kernel.

The default matrix covers the AstrAI 1B q/k/v/out projections, MLP up/gate/down, and LM head for M=1,2,4,8,16,32. Each shape runs in eager and CUDA Graph replay modes. Results include device-event latency samples, p50/p90/p99, estimated effective IO bandwidth, and CUDA kernel launches per call.

CUDA_VISIBLE_DEVICES=0 python csrc/bench/benchmark_gemv.py \
  --output results/decode_linear.json \
  --markdown-output results/decode_linear.md

Use --shape NAME:N:K repeatedly to override the preset and --m-values to change the decode batch sizes. Compare each GPU architecture only with its own baseline; do not use absolute A100-versus-L20 numbers as a dispatch criterion. Keep the raw JSON as the source of truth and generate tables with --markdown-output rather than transcribing measurements by hand.

For direct A/B coverage of the custom kernel and guarded dispatcher across traditional LLaMA and GPT-NeoX decode shapes, use:

CUDA_VISIBLE_DEVICES=0 PYTHONPATH=. python csrc/bench/benchmark_gemv_common.py \
  --suite all --family traditional --m 2 4 \
  --output results/gemv_common.json

The kernel suite compares the directly callable primitive with F.linear. Use repeatable --shape-label and --chain-label filters for a focused run. The synthetic-chain suite alternates ASTRAI_GEMV=0 and auto, includes dependent MLP work and Python dispatch, and rotates through distinct weights. Automatic dispatch is keyed on the decode batch size alone (M in [2, 4] on compute capability 8.0+); use --candidate-mode 1 to characterize a family before widening that band. The checked-in final evidence always uses auto. It is deliberately not labeled a whole-model throughput benchmark. Both suites report median/p90 CUDA-event latency plus maximum absolute error, relative L2 error, and row-wise argmax parity.