Summary

• Adds a separate eigh_v2 linalg problem and leaderboard entry without changing the existing eigh implementation or rankings.
• Carries forward the important robustness ideas from the related eigh PRs: Improve eigh accuracy and benchmark balance #156 benchmark/accuracy balancing by @msaroufim, and eigh_py: reject physically-impossible benchmark times (roofline floor) #159/eigh_py: regenerate a fresh input each timed benchmark iteration #160/eigh_py: reject output-object deferral in the correctness check #161 roofline floor, fresh timed inputs, and output-deferral rejection by @robobryce.
• Does not carry the old profiler-capture cherry-pick from Wrap timed custom_kernel launches in a cudaProfiler capture range (qr_v2, eigh_py) #157 because profile mode is already present on main via Add Eigh profile mode #158.
• Adds block-diagonal correctness cases with varied block sizes, plus additional 512-shape benchmark distributions so precision choices need to respond to matrix quality rather than only public shape IDs.
• Simplifies the checker to the non-redundant hard gates: eigen-equation residual, eigenvalue error against torch.linalg.eigvalsh(A), and orthogonality. Reconstruction is skipped because it follows for square orthonormal Q when the eigen-equation holds.
• Keeps ranked runtime practical by making leaderboard mode use the same rechecked benchmark path instead of the previous 1000-repeat ranked loop.

Validation

• python3 -m py_compile problems/linalg/eigh_v2/eval.py problems/linalg/eigh_v2/reference.py problems/linalg/eigh_v2/task.py problems/linalg/eigh_v2/submissions/torch_eigh.py problems/linalg/eigh_v2/submissions/triton_diagonal_fast_path.py
• /Users/mark/Dev/kernelbot/.venv/bin/ruff check problems/linalg/eigh_v2
• git diff --check
• Local-only KernelBot debug setup against kernelbot_eigh_v2_debug on 127.0.0.1, with the local checkout registered through PROBLEM_DEV_DIR / PROBLEMS_REPO.
• Baseline torch_eigh.py local submissions on B200:
  • test: 41/41 pass
  • benchmark: 10/10 pass
  • real leaderboard submission after repeat-budget fix: pass, about 116s end-to-end locally; recorded phase durations included test at 7-10s, benchmark at 34-44s, and leaderboard at 44-48s.
• Adversarial local submissions:
  • Tensor subclass/output deferral failed in the evaluator with Q must be a plain torch.Tensor.
  • Cache/replay and harness timing patch attempts were rejected by KernelGuard on the normal local API.
  • With KernelGuard disabled only on a separate local debug API, cache/replay still failed evaluator correctness, and forged CUDA-event timing failed the new physical roofline floor.

Provenance

Resolved problem directory: problems/linalg/eigh_v2. Ranked/profile shapes come from eigh_v2/task.yml benchmarks:. Profile mode wraps the submitted kernel in the upstream custom_kernel NVTX region. Reference-kernels base used for this PR: origin/main at 4a1153e, with this branch at 9bcefc4.