Skip to content

Record: Fused LeakyReLU² + Online GPTQ + Parallel Muon — val_bpb 1.117 (1-seed)#1072

Draft
vimeto wants to merge 1 commit intoopenai:mainfrom
vimeto:main
Draft

Record: Fused LeakyReLU² + Online GPTQ + Parallel Muon — val_bpb 1.117 (1-seed)#1072
vimeto wants to merge 1 commit intoopenai:mainfrom
vimeto:main

Conversation

@vimeto
Copy link
Copy Markdown

@vimeto vimeto commented Mar 29, 2026

Fused LeakyReLU² + Online GPTQ + Parallel Muon

val_bpb: 1.117 (1-seed, stride=16, pending 3-seed confirmation)
Artifact: 15.95 MB (with selective ±1 pruning)
No TTT — pure neural model with sliding window evaluation

Key Innovations

1. Fused Triton MLP Kernel — Custom Triton kernel fusing F.linear → LeakyReLU(0.5) → square into one GPU pass. Eliminates the 1536-dim intermediate tensor write to HBM per layer. Result: 70ms/step (vs 87ms without) on 8xH100 SXM → 33% more training steps in the same wallclock.

2. Online Hessian GPTQ — Hessian matrices (H = X^T X) accumulated during training via separate uncompiled forward passes every 25 steps. Eliminates the train-time vs GPTQ-time tradeoff: full 600s training budget + Full GPTQ quality.

3. Selective ±1 Pruning — After INT6 quantization, adaptively zeros the least-significant ±1 weights (sorted by scale²) to precisely control artifact size to ≤16MB.

Results

Seed Steps Step avg Pre-quant Sliding BPB Stride Artifact
1337 7,904 70.0ms 1.1290 1.1170 16 15.95MB
42 pending
2025 pending

3-seed runs pending due to cloud GPU infrastructure instability. Projected 3-seed mean: ~1.117.

Architecture

11L/512d, 8H/4KV GQA, LeakyReLU(0.5)², XSA all 11 layers, BigramHash 4096, VE128 layers 9-10, SmearGate, Partial RoPE 16/64, U-Net skips, LN Scale 1/√(layer+1), logit softcap 30.

Training

Parallel Muon (parameter banking, 3-phase overlapped reduce-scatter/all-gather, no DDP) + Adam. 786K batch, warmdown=3000, QAT@0.5, EMA 0.997, SWA every 50. Online Hessian GPTQ INT6 + LZMA preset=9 + selective ±1 pruning.

Comparison

Entry Sliding BPB TTT?
This (projected) 1.117 No
Merged SOTA (PR #549) 1.1194 Yes
PR #549 pre-TTT 1.1218 No

Credits

Built on: PR #549 (Parallel Muon), PR #414 (base arch), PR #198 (XSA), PR #287 (Partial RoPE), PR #493 (LeakyReLU²), modded-nanogpt (fused kernel pattern).

icryo added a commit to icryo/parameter-golf that referenced this pull request Mar 29, 2026
… reset

Combines the best of three approaches:
  PR openai#1060 (1.1122): coprime loader + Full GPTQ + XSA-all
  PR openai#1072 (1.117):  fused Triton MLP (matmul+activation, 70ms/step)
  Ours:              TTT periodic reset (anti-drift)

Expected: ~7900 steps (vs 6700) with PR openai#1060 quality innovations
= best training throughput + best quantization + best eval.

Fused MLP kernel from PR openai#1072 uses TMA TensorDescriptors (H100 only).
Falls back to standard path on non-Hopper GPUs.

TTT sweep tests 4 configs on the same trained checkpoint:
  sota_ttt, pr1039, reset/100, reset/50

Total H100 time: ~10min train + 4×7min TTT ≈ 40 min

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
icryo added a commit to icryo/parameter-golf that referenced this pull request Mar 30, 2026
Both from top submissions, zero code risk:
  MUON_BACKEND_STEPS=4 (PR openai#1089): 4 NS iterations vs 5
    Saves ~1-2ms/step, proven at 1.1086 BPB
  BIGRAM_VOCAB_SIZE=4096 (PR openai#1072): larger hash table
    More n-gram patterns, proven at 1.117 BPB

MLP 3.5x investigated but doesn't fit 16MB budget (+2.2MB).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Labels

None yet

Projects

None yet

Development

Successfully merging this pull request may close these issues.

1 participant