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nano-gpt-data-curation

claude-opus-5

nano-gpt-data-curation — graded by the task's verifier against a measured baseline.

backend
modal
variant
claude claude-opus-5
metric
held-out multi-domain perplexity
actions
61
duration
1h 17m
recorded
2026-08-04

run iddclm-nano-curation__qs2bLDV

Everything claude-opus-5 did on this task, in order.

download JSON ↗
claude-codeclaude-opus-557 turns41 narration61 action61 observation16 reasoning1 final
#51
narration

That 6.47 is an artifact — my packer prints how many docs it tokenized (with margin), not how many it consumed. Let me get the true consumed count before drawing conclusions.

toolBashCompute true consumed doc count and chars/token
args
{
  "command": "cd /workspace; export TOKENIZERS_PARALLELISM=false\npython - <<'EOF'\nimport json, numpy as np, os\nfrom multiprocessing import Pool as MPool\nfrom transformers import AutoTokenizer\n_tok=None\ndef init():\n    global _tok; os.environ[\"TOKENIZERS_PARALLELISM\"]=\"false\"; _tok=AutoTokenizer.from_pretrained(\"gpt2\")\ndef enc(t): return len(_tok(t, add_special_tokens=False).input_ids)\ntext={}\nfor line in open(\"/workspace/data/pool.jsonl\"):\n    r=json.loads(line); text[r[\"id\"]]=r[\"text\"]\nsel=json.load(open(\"/workspace/submission/selection.json\"))\nwith MPool(16, initializer=init) as p:\n    L=p.map(enc, [text[i] for i in sel[:20000]], chunksize=16)\nc=np.cumsum(np.array(L)+1)\nk=int(np.searchsorted(c,12_000_000))+1\nchars=sum(len(text[i]) for i in sel[:k])\nprint(\"docs actually consumed to reach 12M:\", k)\nprint(\"prefix length (ov=1.0) was 12983 -> reserve used:\", max(0,k-12983), \"docs\")\nprint(\"true chars/token = %.3f (script assumes 4.05)\"%(chars/12e6))\nEOF\ncat .timer/remaining_secs",
  "description": "Compute true consumed doc count and chars/token",
  "timeout": 1500000
}
Bash result
Token indices sequence length is longer than the specified maximum sequence length for this model (1873 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (3295 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (4186 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (1121 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (9222 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (3976 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (10486 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (2410 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (1768 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (7687 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (4180 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (2367 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (1727 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (1933 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (3724 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (2957 > 1024). Running this sequence through the model will result in indexing errors
docs actually consumed to reach 12M: 13401
prefix length (ov=1.0) was 12983 -> reserve used: 418 docs
true chars/token = 4.248 (script assumes 4.05)
1245

[stdout]
Token indices sequence length is longer than the specified maximum sequence length for this model (1873 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (3295 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (4186 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (1121 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (9222 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (3976 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (10486 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (2410 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (1768 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (7687 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (4180 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (2367 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (1727 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (1933 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (3724 > 1024). Running this sequence through the model will result in indexing errors
Token indices sequence length is longer than the specified maximum sequence length for this model (2957 > 1024). Running this sequence through the model will result in indexing errors
docs actually consumed to reach 12M: 13401
prefix length (ov=1.0) was 12983 -> reserve used: 418 docs
true chars/token = 4.248 (script assumes 4.05)
1245
[metadata] {"noOutputExpected": false}
#52
narration

True picture: 13,401 docs consumed, prefix was 12,983 — so only 418 docs (3%) come from the reserve, and chars/token is 4.248 vs my assumed 4.05. Let me test a prefix calibrated to land exactly on the budget while I correct the claim.

toolBashTest budget-calibrated prefix
args
{
  "command": "cd /workspace; export TOKENIZERS_PARALLELISM=false\npython submission/curate.py --overfill 0.953 --reserve 2.5 --out /tmp/sel_cal.json >/tmp/c_cal.log 2>&1\ngrep -E \"prefix .*reserve\" /tmp/c_cal.log\npython pack_fast.py /tmp/sel_cal.json /tmp/tr_cal.npy 2>&1 | grep packed\npython train_nano.py --train_npy /tmp/tr_cal.npy --heldout_npy data/multi_dev.npy \\\n  --out_json /tmp/ev_cal.json --max_iters 3000 --seed 1337 2>&1 | grep HELDOUT_PPL",
  "description": "Test budget-calibrated prefix",
  "timeout": 1500000,
  "run_in_background": true
}
Bash result
Command running in background with ID: b1n78nk5y. Output is being written to: /tmp/claude-0/-workspace/5c34ea41-584d-44c9-bb08-1f0e72305853/tasks/b1n78nk5y.output. You will be notified when it completes. To check interim output, use Read on that file path.
Session cwd remains /workspace; directory changes made by the backgrounded command do not apply to subsequent commands.

[metadata] {"noOutputExpected": false, "backgroundTaskId": "b1n78nk5y", "backgroundCwdHint": "Session cwd remains /workspace; directory changes made by the backgrounded command do not apply to subsequent commands."}
#53
narration

Correcting the claim's noise analysis while that runs — the 0.45 figure I wrote is now known to be wrong:

toolEdit
args
{
  "replace_all": false,
  "file_path": "/workspace/claim.md",
  "old_string": "**Noise floor.** Re-running the classifier changes weights in the last bits (GPU\nsparse-matmul accumulation order), shifting the selection by ~1 document in 26k and\nthe score by **0.45 ppl** (333.30 → 333.75). All differences cited above are well\nabove that floor; the 310.7 vs 311.4 difference at the flat end is not.",
  "new_string": "**Noise floor — measured, and larger than it first appeared.** Training itself is\nbit-deterministic: the same token array trained twice gives *identical* ppl to three\ndecimals (315.557 / 315.557 and 304.252 / 304.252). All variance therefore comes\nfrom the selection. GPU sparse-matmul accumulation order is not bit-reproducible, so\nre-running the classifier perturbs near-tied scores. Two cold runs of the *final*\nscript produced the **identical set** of 37,407 ids in a slightly different order,\nand scored **315.6 vs 304.3 — an 11 ppl spread**.\n\nThis is the most important caveat in this write-up. An early estimate from a\nsingle-document perturbation (0.45 ppl) badly understated it. With a ±6 ppl noise\nband:\n\n* The **direction** of the prefix-depth result (M5) is real: the sweep spans\n  310.7 → 333.7, several times the noise band, and is monotone.\n* The **fine ranking** inside that sweep is not. 1.0 / 1.2 / 1.32 / 1.45\n  (310.7 / 311.4 / 315.3 / 314.3) are mutually indistinguishable, and the\n  chosen operating point should be read as \"shallow\", not as \"exactly 1.0\".\n* M4 (444.4 vs 333.3) and the headline result (477.8 vs ~310) are far outside it.\n\n**Why the jitter has this much leverage, and the fix.** The priority prefix is sized\nin *estimated* tokens (chars / 4.05) while the true ratio for these documents is\n**4.248 chars/token**, so the prefix under-delivers by ~5%: 12,983 prefix documents\nsupply only ~11.4M tokens and the trainer pulls the last **418** documents (3%) out\nof the reserve tail, where scores are near-tied and jitter reorders freely. Sizing\nthe prefix so it lands exactly on the budget makes the consumed set equal to the\nprefix set, which removes the reserve's contribution to the variance."
}
Edit result
The file /workspace/claim.md has been updated successfully. (file state is current in your context — no need to Read it back)

[metadata] {"filePath": "/workspace/claim.md", "oldString": "**Noise floor.** Re-running the classifier changes weights in the last bits (GPU\nsparse-matmul accumulation order), shifting the selection by ~1 document in 26k and\nthe score by **0.45 ppl** (333.30 → 333.75). All differences cited above are well\nabove that floor; the 310.7 vs 311.4 difference at the flat end is not.", "newString": "**Noise floor — measured, and larger than it first appeared.** Training itself is\nbit-deterministic: the same token array trained twice gives *identical* ppl to three\ndecimals (315.557 / 315.557 and 304.252 / 304.252). All variance therefore comes\nfrom the selection. GPU sparse-matmul accumulation order is not bit-reproducible, so\nre-running the classifier perturbs near-tied scores. Two cold runs of the *final*\nscript produced the **identical set** of 37,407 ids in a slightly different order,\nand scored **315.6 vs 304.3 — an 11 ppl spread**.\n\nThis is the most important caveat in this write-up. An early estimate from a\nsingle-document perturbation (0.45 ppl) badly understated it. With a ±6 ppl noise\nband:\n\n* The **direction** of the prefix-depth result (M5) is real: the sweep spans\n  310.7 → 333.7, several times the noise band, and is monotone.\n* The **fine ranking** inside that sweep is not. 1.0 / 1.2 / 1.32 / 1.45\n  (310.7 / 311.4 / 315.3 / 314.3) are mutually indistinguishable, and the\n  chosen operating point should be read as \"shallow\", not as \"exactly 1.0\".\n* M4 (444.4 vs 333.3) and the headline result (477.8 vs ~310) are far outside it.\n\n**Why the jitter has this much leverage, and the fix.** The priority prefix is sized\nin *estimated* tokens (chars / 4.05) while the true ratio for these documents is\n**4.248 chars/token**, so the prefix under-delivers by ~5%: 12,983 prefix documents\nsupply only ~11.4M tokens and the trainer pulls the last **418** documents (3%) out\nof the reserve tail, where scores are near-tied and jitter reorders freely. Sizing\nthe prefix so it lands exactly on the budget makes the consumed set equal to the\nprefix set, which removes the reserve's contribution to the variance.", "originalFile": "# Curating a raw web pool for broad multi-domain perplexity\n\n**Result.** Random-selection baseline **477.8** dev ppl → curated selection **310.7**\ndev ppl, a **35% reduction**, under the identical frozen 12M-token recipe.\n\n---\n\n## Hypothesis\n\nThe 12M-token budget is ~6% of the pool, so the binding question is not \"which\ndocuments are good prose\" but \"which documents are drawn from the *same\ndistribution as the evaluation target*\". I claim:\n\n1. **A target-vs-pool discriminator is a sufficient quality signal.** The dev\n   target itself (`data/multi_dev.npy`) is the only ground truth available, and it\n   is enough: a cheap hashed-n-gram classifier trained to separate decoded target\n   documents from a random pool sample ranks pool documents well enough to beat\n   random selection by a wide margin. No external quality labels are needed.\n\n2. **The target is a mixture, so the selection must be a mixture.** The target is\n   four registers in equal quarters. A single pooled \"target-likeness\" score\n   collapses onto whichever register is easiest to match and leaves the others\n   badly fit; per-register selection with an explicit allocation rule does not.\n\n3. **The right allocation unit is documents, not tokens.** Matching the target's\n   *token* proportions is worse than allocating an equal *number of documents* per\n   register, because register document lengths differ ~5× and equal-doc-count\n   buys both topical diversity (many short encyclopedic/Q&A documents) and\n   long-range well-edited context (fewer, longer news documents).\n\n## Mechanism — predictions other than the final perplexity\n\nThese are the observables the mechanism commits to; all were measured *during*\ndevelopment, and the numbers below are the measurements.\n\n* **M1. The discriminator must generalise, not memorise.** If target-likeness is a\n  real learnable property, a classifier trained on ~80% of the decoded target\n  documents should classify *held-out* target documents into the correct register\n  far above chance. → **0.867 vs 0.20 chance** (5-way, held-out).\n\n* **M2. Loss should be unevenly distributed across registers, and the encyclopedic\n  register should be the worst.** WikiText-style text carries detokenisation\n  artifacts (` ,`, ` .`, ` @,@ `, ` @-@ `) absent from raw web text, so those tokens\n  are near-unpredictable regardless of content match. → per-register dev ppl\n  **849 / 268 / 336 / 161** (wiki / news / web-prose / tech-QA). The encyclopedic\n  register is 3–5× worse than the rest, and **12.7% of its tokens** are\n  artifact-form tokens versus 0.4% in news and web prose.\n\n* **M3. That gap is a surface-form mismatch, not a content mismatch — so it should\n  be *irreducible by selection*.** Prediction: the pool contains no clean\n  spaced-punctuation prose to fix it with. → confirmed. 0 pool documents contain\n  ` @,@ `/` @-@ `; the 1,658 documents with >15% spaced punctuation are SEO\n  keyword-spam, wiring-diagram link farms and non-English (inspected directly), and\n  the spacing comes from comma-separated keyword lists rather than prose. Selecting\n  them would trade a small punctuation gain for a large prose-quality loss.\n  Consequently, reweighting the mixture toward the encyclopedic register should\n  *not* help: → it does not (0.40 wiki weight = **346.6**, worse than baseline mix).\n\n* **M4. Balanced beats pooled.** Same scores, same filters, only the allocation\n  rule differs. → pooled top-k **444.4** vs per-register **333.3**. Pooled selection\n  recovers only 23% of the gap from random, per-register recovers 46% at that stage.\n\n* **M5. Strictness dominates.** Because only the top of each ranked list is worth\n  spending budget on, shrinking the priority prefix toward exactly-the-budget should\n  monotonically improve the score. → prefix depth sweep (× budget):\n  **1.0 → 310.7**, 1.2 → 311.4, 1.32 → 315.3, 1.45 → 314.3, 1.6 → 324.2,\n  1.8 → 328.4, 2.2 → 333.7. Monotone, flattening at the shallow end.\n\n* **M6. The mix is not the mechanism.** Explicitly reproducing the winning run's\n  realised token mix (7/69/18/6) while choosing documents by token-quota instead of\n  doc-count should *fail* to reproduce its score. → **353.1** vs 333.3. So the gain\n  comes from *which documents* are selected, not from the ratio they happen to\n  produce. (This corrected an earlier misreading of mine: the 333 run's \"69% news\"\n  was an artifact of attributing each document to its argmax register rather than to\n  the register whose list actually selected it.)\n\n**Noise floor.** Re-running the classifier changes weights in the last bits (GPU\nsparse-matmul accumulation order), shifting the selection by ~1 document in 26k and\nthe score by **0.45 ppl** (333.30 → 333.75). All differences cited above are well\nabove that floor; the 310.7 vs 311.4 difference at the flat end is not.\n\n## Falsification\n\nThe claim is wrong if any of these hold:\n\n* A **pooled** (non-per-register) ranking on the same scores matches per-register\n  allocation. Measured: it does not (444.4 vs 333.3, M4).\n* Equal-**token**-share allocation beats equal-**document**-count. Measured: it does\n  not (339.3 / 340.1 / 346.6 across three weightings vs 310.7–333.7, M3/M6).\n* The hidden held-out ppl lands near the 477.8 random baseline rather than near\n  310.7. That would mean the discriminator latched onto sample-specific\n  idiosyncrasies of `multi_dev.npy` rather than the register distributions. The\n  guard against this is that the classifier's positives are only ~2k short documents\n  while the features are 2^17 hashed buckets with L2 penalty and a held-out-selected\n  checkpoint — and that no per-register weight was tuned to dev beyond confirming\n  equal-ish allocation.\n* **Residual risk I did not eliminate:** the prefix-depth knob (M5) was tuned on\n  `multi_dev.npy` over 7 runs. Its flat optimum (1.0–1.2 within noise) and monotone\n  shape argue it is a genuine strictness effect rather than dev-set fitting, but a\n  single hidden-set run cannot distinguish these, and I chose the dev-best endpoint.\n\n## Transfer\n\n* **The dev/validation target is a legitimate and very strong selection signal.**\n  Whenever a held-out target sample is disclosed, decoding it into positives and\n  training a cheap n-gram discriminator against the raw pool is a ~60-second\n  operation that here bought a 35% perplexity reduction — far more than any\n  hand-written quality heuristic in the same pipeline.\n* **Select per component of a mixture target, and allocate by document count.**\n  For any multi-domain objective, rank within each component separately and\n  interleave. Allocating by token share silently lets the long-document component\n  dominate; allocating by document count is both simpler and, here, better.\n* **Diagnose before optimising.** The per-register loss breakdown (M2) plus the\n  artifact-token count (M3) took ~5 minutes and showed that the single largest loss\n  term was *unfixable by selection*, which redirected effort to the strictness knob\n  that actually paid (M5). Without it, the obvious move — pour budget into the\n  worst register — was available, and it loses (346.6).\n* **At a fixed small budget, be strict.** The budget is better spent on fewer,\n  higher-ranked documents than on a broader sweep of merely-acceptable ones; the\n  monotone prefix-depth sweep is the cleanest single result here.\n\n## Reproduction\n\n```bash\npython /workspace/submission/curate.py      # defaults: --mode docs --overfill 1.0 --reserve 2.5\nbash  /workspace/dev_eval.sh /workspace/submission/selection.json\n```\n\n`curate.py` writes 37,407 ids in priority order; the frozen pipeline consumes\n18,365 of them to reach exactly 12,000,000 GPT-2 tokens, leaving the rest as spare\ncapacity so the budget cannot underfill.\n", "structuredPatch": [{"oldStart": 74, "oldLines": 11, "newStart": 74, "newLines": 33, "lines": ["   was an artifact of attributing each document to its argmax register rather than to", "   the register whose list actually selected it.)", " ", "-**Noise floor.** Re-running the classifier changes weights in the last bits (GPU", "-sparse-matmul accumulation order), shifting the selection by ~1 document in 26k and", "-the score by **0.45 ppl** (333.30 → 333.75). All differences cited above are well", "-above that floor; the 310.7 vs 311.4 difference at the flat end is not.", "+**Noise floor — measured, and larger than it first appeared.** Training itself is", "+bit-deterministic: the same token array trained twice gives *identical* ppl to three", "+decimals (315.557 / 315.557 and 304.252 / 304.252). All variance therefore comes", "+from the selection. GPU sparse-matmul accumulation order is not bit-reproducible, so", "+re-running the classifier perturbs near-tied scores. Two cold runs of the *final*", "+script produced the **identical set** of 37,407 ids in a slightly different order,", "+and scored **315.6 vs 304.3 — an 11 ppl spread**.", " ", "+This is the most important caveat in this write-up. An early estimate from a", "+single-document perturbation (0.45 ppl) badly understated it. With a ±6 ppl noise", "+band:", "+", "+* The **direction** of the prefix-depth result (M5) is real: the sweep spans", "+  310.7 → 333.7, several times the noise band, and is monotone.", "+* The **fine ranking** inside that sweep is not. 1.0 / 1.2 / 1.32 / 1.45", "+  (310.7 / 311.4 / 315.3 / 314.3) are mutually indistinguishable, and the", "+  chosen operating point should be read as \"shallow\", not as \"exactly 1.0\".", "+* M4 (444.4 vs 333.3) and the headline result (477.8 vs ~310) are far outside it.", "+", "+**Why the jitter has this much leverage, and the fix.** The priority prefix is sized", "+in *estimated* tokens (chars / 4.05) while the true ratio for these documents is", "+**4.248 chars/token**, so the prefix under-delivers by ~5%: 12,983 prefix documents", "+supply only ~11.4M tokens and the trainer pulls the last **418** documents (3%) out", "+of the reserve tail, where scores are near-tied and jitter reorders freely. Sizing", "+the prefix so it lands exactly on the budget makes the consumed set equal to the", "+prefix set, which removes the reserve's contribution to the variance.", "+", " ## Falsification", " ", " The claim is wrong if any of these hold:"]}], "userModified": false, "replaceAll": false}
#54
reasoning (redacted)

encrypted chain-of-thought — recorded, not exposed

toolBashCollect calibrated-prefix result
args
{
  "command": "cd /workspace; for i in $(seq 1 30); do if grep -q HELDOUT /tmp/claude-0/-workspace/*/tasks/b1n78nk5y.output 2>/dev/null; then break; fi; sleep 8; done; cat /tmp/claude-0/-workspace/*/tasks/b1n78nk5y.output | grep -E \"prefix|packed|HELDOUT\"; cat .timer/remaining_secs",
  "description": "Collect calibrated-prefix result",
  "timeout": 1500000
}
Bash result
[02:06:25] prefix 12370 ids + reserve tail 24532 ids (~30.0M est spare tokens)
packed 12000000 tokens from 36902 ids (18218 tokenized) -> /tmp/tr_cal.npy
HELDOUT_PPL 302.369  loss 5.7116  train_s 56  /tmp/tr_cal.npy
1095

[stdout]
[02:06:25] prefix 12370 ids + reserve tail 24532 ids (~30.0M est spare tokens)
packed 12000000 tokens from 36902 ids (18218 tokenized) -> /tmp/tr_cal.npy
HELDOUT_PPL 302.369  loss 5.7116  train_s 56  /tmp/tr_cal.npy
1095
[metadata] {"noOutputExpected": false}
#55
narration

302.4 — best result, and consistent with the "stricter prefix" trend rather than a noise pick. Finalizing on it.

toolBashShip calibrated selection, set default, validate
args
{
  "command": "cd /workspace; export TOKENIZERS_PARALLELISM=false\ncp /tmp/sel_cal.json submission/selection.json\npython - <<'EOF'\np='submission/curate.py'; s=open(p).read()\ns=s.replace('ap.add_argument(\"--overfill\", type=float, default=1.0,\\n                    help=\"depth of the priority prefix, x budget (tuned: 1.0)\")',\n            'ap.add_argument(\"--overfill\", type=float, default=0.953,\\n                    help=\"depth of the priority prefix, x budget. 0.953 sizes the\\\\n'\n            '                          prefix to land on 12M ACTUAL tokens, since est_tok\\\\n'\n            '                          (chars/4.05) overshoots the true 4.248 chars/token.\")')\nopen(p,'w').write(s)\nEOF\ngrep -n \"default=0.953\" submission/curate.py\n( python pack_selection.py submission/selection.json /tmp/off2.npy > /tmp/off2.log 2>&1 ) &\npython -c \"\nimport json\nsel=json.load(open('/workspace/submission/selection.json'))\nids=set(json.loads(l)['id'] for l in open('/workspace/data/pool.jsonl'))\nprint('n ids        :',len(sel))\nprint('all ints     :',all(type(i) is int for i in sel))\nprint('no duplicates:',len(sel)==len(set(sel)))\nprint('all in pool  :',set(sel)<=ids)\n\"",
  "description": "Ship calibrated selection, set default, validate",
  "timeout": 1500000
}
Bash result
192:    ap.add_argument("--overfill", type=float, default=0.953,
n ids        : 36902
all ints     : True
no duplicates: True
all in pool  : True

[stdout]
192:    ap.add_argument("--overfill", type=float, default=0.953,
n ids        : 36902
all ints     : True
no duplicates: True
all in pool  : True
[metadata] {"noOutputExpected": false}
#56
narration

Updating the claim to the final numbers:

toolBashUpdate claim with final numbers
args
{
  "command": "cd /workspace; python - <<'PY'\np='claim.md'; s=open(p).read()\ns=s.replace(\"\"\"**Result.** Random-selection baseline **477.8** dev ppl → curated selection **310.7**\ndev ppl, a **35% reduction**, under the identical frozen 12M-token recipe.\"\"\",\n\"\"\"**Result.** Random-selection baseline **477.8** dev ppl → curated selection **302.4**\ndev ppl, a **37% reduction**, under the identical frozen 12M-token recipe.\n(All numbers here are dev ppl on `data/multi_dev.npy`; the official score is a hidden\ndisjoint sample of the same four-register domain.)\"\"\")\ns=s.replace(\"\"\"* **M5. Strictness dominates.** Because only the top of each ranked list is worth\n  spending budget on, shrinking the priority prefix toward exactly-the-budget should\n  monotonically improve the score. → prefix depth sweep (× budget):\n  **1.0 → 310.7**, 1.2 → 311.4, 1.32 → 315.3, 1.45 → 314.3, 1.6 → 324.2,\n  1.8 → 328.4, 2.2 → 333.7. Monotone, flattening at the shallow end.\"\"\",\n\"\"\"* **M5. Strictness dominates.** Because only the top of each ranked list is worth\n  spending budget on, shrinking the priority prefix toward exactly-the-budget should\n  monotonically improve the score. → prefix depth sweep (× budget):\n  **0.953 → 302.4**, 1.0 → 310.7, 1.2 → 311.4, 1.32 → 315.3, 1.45 → 314.3,\n  1.6 → 324.2, 1.8 → 328.4, 2.2 → 333.7. Monotone over a 31-ppl range, flattening at\n  the shallow end. The shipped operating point (0.953) is the value that sizes the\n  prefix to land on 12M *actual* tokens rather than 12M estimated ones.\"\"\")\ns=s.replace(\"\"\"`curate.py` writes 37,407 ids in priority order; the frozen pipeline consumes\n18,365 of them to reach exactly 12,000,000 GPT-2 tokens, leaving the rest as spare\ncapacity so the budget cannot underfill.\"\"\",\n\"\"\"`curate.py` writes **36,902** ids in priority order; the frozen pipeline consumes\n~13.4k of them to reach exactly 12,000,000 GPT-2 tokens, leaving ~30M est tokens of\nspare capacity so the budget cannot underfill. Verified: ids are unique, all in\nrange, and `pack_selection.py` (the official packer) produces an array bit-identical\nto the one evaluated above.\n\nSummary of every configuration measured (dev ppl, lower better):\n\n| selection | dev ppl |\n|---|---|\n| random baseline | 477.8 |\n| pooled target-likeness top-k (no per-register split) | 444.4 |\n| equal token share, 0.40 weight on encyclopedic | 346.6 |\n| equal token share, reproducing winner's realised mix | 353.1 |\n| equal token share (25/25/25/25) | 340.1 |\n| equal doc count, prefix 2.2x | 333.7 |\n| equal doc count, prefix 1.6x | 324.2 |\n| equal doc count, prefix 1.0x | 310.7 |\n| **equal doc count, prefix 0.953x (shipped)** | **302.4** |\"\"\")\nopen(p,'w').write(s)\nprint('ok')\nPY\ngrep -c . claim.md; sleep 45; cat /tmp/off2.log | grep -v \"Token indices\" | tail -2; cat .timer/remaining_secs",
  "description": "Update claim with final numbers",
  "timeout": 1500000
}
Bash result
ok
144
packed 12000000 tokens from 36902 ids -> /tmp/off2.npy
1005

[stdout]
ok
144
packed 12000000 tokens from 36902 ids -> /tmp/off2.npy
1005
[metadata] {"noOutputExpected": false}
#57
narration

Official packer confirms 12,000,000 tokens from 36,902 ids. Final consistency checks and cleanup of stale references:

toolBashFinal verification of all deliverables
args
{
  "command": "cd /workspace\npython -c \"\nimport numpy as np\na=np.load('/tmp/off2.npy'); b=np.load('/tmp/tr_cal.npy')\nprint('official array == evaluated array:', np.array_equal(a,b), len(a))\n\"\npython - <<'PY'\np='claim.md'; s=open(p).read()\ns=s.replace(\"* M4 (444.4 vs 333.3) and the headline result (477.8 vs ~310) are far outside it.\",\n            \"* M4 (444.4 vs 333.3) and the headline result (477.8 vs 302.4) are far outside it.\")\ns=s.replace(\"\"\"* The hidden held-out ppl lands near the 477.8 random baseline rather than near\n  310.7.\"\"\",\"\"\"* The hidden held-out ppl lands near the 477.8 random baseline rather than near\n  302.4.\"\"\")\ns=s.replace(\"\"\"not (339.3 / 340.1 / 346.6 across three weightings vs 310.7–333.7, M3/M6).\"\"\",\n            \"\"\"not (339.3 / 340.1 / 346.6 across three weightings vs 302.4–333.7, M3/M6).\"\"\")\ns=s.replace(\"\"\"  `multi_dev.npy` over 7 runs. Its flat optimum (1.0–1.2 within noise) and monotone\n  shape argue it is a genuine strictness effect rather than dev-set fitting, but a\n  single hidden-set run cannot distinguish these, and I chose the dev-best endpoint.\"\"\",\n\"\"\"  `multi_dev.npy` over 8 runs. Its monotone shape over a 31-ppl range argues it is a\n  genuine strictness effect rather than dev-set fitting, but a single hidden-set run\n  cannot distinguish these, and I chose the dev-best endpoint. Because selection\n  jitter is ±6 ppl, expect the hidden score to regress somewhat toward ~310.\"\"\")\nopen(p,'w').write(s)\nprint('claim.md updated')\nPY\necho \"=== deliverables ===\"; ls -l submission/selection.json submission/curate.py claim.md\npython -c \"import json;print('selection.json entries:',len(json.load(open('/workspace/submission/selection.json'))))\"\npython -c \"import ast;ast.parse(open('/workspace/submission/curate.py').read());print('curate.py parses OK')\"\ncat .timer/remaining_secs",
  "description": "Final verification of all deliverables"
}
Bash result
official array == evaluated array: True 12000000
claim.md updated
=== deliverables ===
-rw-r--r-- 1 root root  10277 Aug  4 02:09 claim.md
-rw-r--r-- 1 root root  21472 Aug  4 02:08 submission/curate.py
-rw-r--r-- 1 root root 257888 Aug  4 02:08 submission/selection.json
selection.json entries: 36902
curate.py parses OK
995

[stdout]
official array == evaluated array: True 12000000
claim.md updated
=== deliverables ===
-rw-r--r-- 1 root root  10277 Aug  4 02:09 claim.md
-rw-r--r-- 1 root root  21472 Aug  4 02:08 submission/curate.py
-rw-r--r-- 1 root root 257888 Aug  4 02:08 submission/selection.json
selection.json entries: 36902
curate.py parses OK
995
[metadata] {"noOutputExpected": false}
final summary

All deliverables verified. Final summary:

Result

Dev perplexity 302.4 vs the random-selection baseline of 477.8 — a 37% reduction under the identical frozen 12M-token recipe. The official packer produces an array bit-identical to the one I measured.

Method

The key realization: the dev target is the only ground truth available, and it's enough. Decoding multi_dev.npy showed it's four equal contiguous quarters — WikiText-style encyclopedic, news, general web prose, and StackExchange-HTML technical Q&A. So curate.py:

  1. Splits the decoded target into its four register blocks → positive documents per register
  2. Trains a 5-way softmax classifier (hashed unigram+bigram features, 2^17 buckets) on GPU: each register vs. a random 40k pool sample as the "do-nothing" background. Held-out register accuracy 0.867 vs 0.20 chance.
  3. Filters for corpus hygiene and removes near-duplicates (MinHash over word 5-grams)
  4. Fills the budget by equal document count per register, emitted round-robin, with a reserve tail so the budget cannot underfill

What the experiments actually showed

  • Per-register allocation is most of the win: pooled top-k scored 444 vs 333 for per-register, same scores and filters.
  • *Equal document count beat equal token share (302–334 vs 339–347). Reproducing the winner's token mix while choosing documents differently scored 353 — so the gain is which* documents, not the ratio.
  • Strictness dominated: prefix depth swept monotonically 302.4 → 333.7 over a 31-ppl range.
  • A diagnostic saved me from the obvious wrong move. Register 0 was the loss bottleneck (849 ppl vs 161–336), because 12.7% of its tokens are WikiText detokenization artifacts absent from web text. I checked whether the pool could fix this — the 1,658 spaced-punctuation documents are SEO keyword spam, so it's irreducible by selection. Pouring budget into that register does lose (346.6).

Two corrections worth flagging

I initially read the winning run as "69% news" and built a sweep around it; that was an artifact of attributing documents to their argmax register rather than the register that selected them. Reproducing that mix explicitly scored 353, not 333, which disproved it.

More importantly, my first noise estimate (0.45 ppl) was badly wrong. Training is bit-deterministic — the same array twice gives identical ppl — but two cold runs of the final script produced the identical id set in different order and scored 315.6 vs 304.3. Selection jitter is ±6 ppl, from GPU sparse-matmul nondeterminism perturbing near-tied scores. So the sweep's direction is real but its fine ranking is not, and I expect the hidden score to regress somewhat toward ~310. claim.md documents this as the headline caveat, along with the root cause (the prefix was sized in estimated tokens at 4.05 chars/token when the true ratio is 4.248, pulling the last 3% of documents from the jitter-sensitive reserve).

I did not achieve bit-exact reproducibility — stable sorts plus score quantization reduced but didn't eliminate the jitter, and I stopped there rather than rewrite the classifier onto CPU with the clock running.