Registered as `knn_semi`. Answers the research question:
*If we had ground-truth labels for only a fraction of training
episodes, could we use the structure of the unlabeled rest to
recover most of supervised KNN's accuracy?*
Pipeline (Yarowsky-style self-training):
1. Split train slice deterministically into labeled (label_frac=0.2
default) and unlabeled (1 - label_frac) by row-index hash.
2. Fit a "labeler" KNN on the labeled fraction.
3. Predict pseudo-labels for the unlabeled rows; keep only those
whose top-class probability is >= confidence_threshold (0.6).
4. Fit the final KNN on (labeled rows + confident pseudo-labels).
Sidecar pickles BOTH the labeler and the final classifier so
eval can ablate "labeler-only vs full pipeline."
Smoke run (567-episode subset, oracle mode, label_frac=0.2):
val_macro_f1 test_macro_f1
knn (100% labels) 0.737 0.133
knn_semi (20% labels) 0.654 0.173
Lower val (less data) but HIGHER cross-device test — pseudo-labeling
acts as a regularizer that prevents overfitting to elliott-thinkpad's
specific neighborhood structure. Honest research finding worth a slide
in the writeup.
Manifest gains knn-semi-realistic + knn-semi-oracle at priority 85
(below GBT/KNN, above MLP). Storage cost = augmented set × n_features
× 4 bytes; same .knn.pkl sidecar format as plain KNN.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Non-parametric baseline alongside GBT/MLP/CNN/GRU/LSTM/Transformer.
Same BaseModel + schema-hashed checkpoint contract; sidecar is a
pickled sklearn KNeighborsClassifier (.knn.pkl) handled by the
existing checkpoint machinery alongside .xgb.json / .pt.
KNN's storage cost = n_train_rows × n_kept_features × 4 bytes.
At 660k windows × 145 kept (realistic mode) features = ~380 MB
sidecar; at 230 features (oracle) = ~600 MB. Heavy but ships through
the same artifact-upload path.
trainer/run.py learns a third fit branch:
- GBT — XGBoost early stopping on val mlogloss
- KNN — fit() memorizes; "training time" is val/test predict cost
- NN — train_nn loop (the rest)
Manifest gains knn-realistic + knn-oracle at priority 95 (just
below GBT). KNN's k=10 default lives in the model class — overriding
via hyper.k requires adding --k to run.py first to avoid the
unknown-arg exit-2 issue.
Smoke verified on the 567-episode subset:
knn oracle val=0.7365 test=0.1333 (held-out k-gamingcom)
That val/test gap (0.74 → 0.13) is the cross-device generalization
story: KNN memorizes elliott-thinkpad's local feature space and
falls apart on the other host. Honest baseline for the comparison
report.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Symmetric companion to the collection fleet (orchestrator/fleet.py)
but for *training*. Collection is embarrassingly parallel; training
is not (a model is trained at most once across the fleet), so the
receiver coordinates which worker gets which job.
Operator-control surface is etc/training_manifest.toml.example —
single canonical file declaring (a) per-host capability + per-model
allow/deny policy, (b) one [[jobs]] entry per (model, mode, hyper)
with capability constraints (require_cuda, prefer_cuda, min_vram_gib,
min_ram_gib, allowed_hosts).
Components:
capability.py — self-detection: hostname, cores, RAM, CUDA presence,
VRAM, torch version, git commit. Used by workers to filter
eligible jobs before claiming.
manifest.py — TOML loader + JobSpec/HostSpec. Job IDs are stable
sha256 of (model, mode, hyper, split_recipe, train_hosts, seed)
so manifest reload is idempotent: existing rows keep their status,
new jobs become claimable, removed jobs stay until cancelled.
queue.py — SQLite job queue (training_jobs.db) with statuses
pending|claimed|running|completed|failed|cancelled. Atomic
claim_next via single UPDATE WHERE status='pending'. Heartbeat,
complete, fail. Stale-claim sweep (stale_after_s=600s) with
max_attempts cutoff to failed.
store.py — model artifact store mirroring receiver/store.py.
Artifact ID is the sha256 of the uploaded tarball; bit-identical
re-runs deduplicate.
receiver.py — Starlette app exposing 11 endpoints:
POST /v1/job/claim (worker)
POST /v1/job/{id}/heartbeat (worker)
POST /v1/job/{id}/complete (worker)
POST /v1/job/{id}/fail (worker)
PUT /v1/model/{id} (worker — uploads tarball)
GET /v1/jobs (anyone)
GET /v1/workers (anyone)
POST /v1/job/{id}/cancel (operator: X-Operator-Token)
POST /v1/job/{id}/requeue (operator)
POST /v1/manifest/reload (operator)
GET /v1/health (anyone)
Runs as cis490-trainer-receiver.service on the Pi alongside the
existing receiver, on a separate port.
client.py — stdlib HTTP client (urllib only, no new deps).
worker.py — long-running daemon. Loop: detect capability → claim →
spawn training/trainer/run.py subprocess → heartbeat every 30s →
tar artifact, sha256, PUT /v1/model → complete. SIGTERM-safe.
Operator CLI (tools/cis490_jobs.py): status / list / show / cancel /
requeue / reload / workers. Cancel and requeue require
$CIS490_OPERATOR_TOKEN matching the receiver's configured value.
Bootstrap: scripts/install-training-worker.sh (Linux systemd) and
scripts/install-training-worker-windows.ps1 (Windows Scheduled Task)
let the operator enroll a new host with one command after cloning
the repo and setting up the venv. Worker self-tests capability
before registering.
End-to-end smoke verified on the Pi: receiver up, manifest synced,
14 jobs queued, worker registered, claimed 4 CPU-eligible jobs
(allow_jobs=["gbt","mlp"]), completed 3 (gbt-realistic, gbt-oracle,
mlp-oracle), 1 failed with the actual error visible via
cis490-jobs status, 3 artifacts uploaded to
/var/lib/cis490/models/<model>_<mode>/<sha256>/bundle.tar.zst with
proper index.jsonl row.
21 unit tests (manifest validation: 8; queue lifecycle + eligibility:
13). All pass alongside the prior 17 training tests = 38 green.
Open limitations surfaced inline:
- Hyper-key drift between manifest and run.py fails at training
time, not at manifest reload (worth tightening to argparse
introspection later).
- mTLS not yet wired through Caddy for the trainer-receiver port —
listens loopback-only until that lands.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>