| name | qcu |
| description | examples/qcu 目录的完整生成 skill：经 Cython 桥测 C++ CUDA 后端；含 dev73_5 多重网格性能基准套件（clean/bench/verify/collect/mktable/plots）。 |
CLAUDE.md — examples/qcu
C++ CUDA backend tests via the Cython bridge. These exercise libqcu.so from Python.
Test Files
| File | What it tests |
|---|
conftest.cuda.py | Basic CUDA availability and context |
conftest.mpi.py | MPI grid setup and halo exchange |
conftest.wilson.bistabcg.py | Wilson BiStabCG via C++ backend |
conftest.wilson.bistabcg.dslash.py | Wilson BiStabCG dslash kernel |
conftest.wilson.cg.py | Wilson CG solver |
conftest.clover.py | Clover term construction |
conftest.clover.bistabcg.py | Clover BiStabCG solver |
conftest.clover.bistabcg.dslash.py | Clover BiStabCG dslash |
conftest.clover.multigrid.py | Clover multigrid V-cycle solver |
Usage
mpirun -np 1 python examples/qcu/conftest.clover.multigrid.py
Output: convergence log → logs/clover_multigrid.log, performance report → logs/clover_multigrid_report.log
Dev73_5 Multigrid Benchmark Suite
Development scripts for the dev73_5 multigrid performance milestone. They benchmark applyCloverMultigridQcu against the Clover BiStabCG reference (applyCloverBistabCgQcu) across precision / lattice / solver-parameter sweeps, and feed logs/dev73_5.* (report, LaTeX tables, PNG figures).
Scripts are archived under examples/qcu/dev73/ (outputs → logs/dev73/):
| File | Purpose |
|---|
dev73/mg_dev73_5_clean.py | Clean, isolated-process timing of a single config (ref/mg interleaved, min+median speedup) |
dev73/mg_dev73_5_bench.py | Extended performance benchmark — precision / lattice / solver-parameter sweeps vs BiStabCG |
dev73/mg_dev73_5_verify.py | Correctness checks — SU(3) gauge, solution error, null-vector zero-mode/orthogonality, C++ vs Python coarse dslash |
dev73/mg_dev73_5_collect.py | Aggregate clean/bench/verify JSON into logs/dev73_5_results.json |
dev73/mg_dev73_5_mktable.py | Emit LaTeX table snippets (logs/dev73_5_tbl_*.tex) for dev73_5.tex |
dev73/mg_dev73_5_plots.py | Generate convergence / hotspot / speedup / time PNG figures into logs/ |
Newer dev74 / dev74_1 suites live in examples/qcu/dev74/ (outputs → logs/dev74/); the test11/test12 integration suites live in logs/test11/, logs/test12/ (see the test12 skill).
Dev84 Multigrid 攻坚套件（当前版）
examples/qcu/dev84/main.py — 子命令 run / multi / run_gcr / hotspot（带 --only 门控），产物镜像 out/*.json 与 logs/dev84/；报告 examples/qcu/dev84/dev84_report.md。
结论（16×32×32×48 统一格子）：粗空间 ρ_V=0.9759（连续谱无孤立低模簇），MG>2 目标不可达；
体积标度 1.5× 体量仅 0.421×，「大格子有利」证伪。但净优化使 V100 上 MG 首次稳定超 BiStabCG
1.13–1.16×，自适应校正门控再降 MG_2L −18%。机制：CUDA Graph 段回放（8 迭代/段）、零拷贝标量、守卫标量内核、粗解开销 3246→4ms、V-cycle 156→60ms。
剖析工具边界：nvprof 可用（权威）；torch.profiler/kineto 捕不到跨线程 C++ 内核；nsys 在 WSL2 失效。
