# Iteration 2 Log ## Metadata - **Task ID**: DGR-013 - **Task Title**: Harden failure, cancellation, and restart semantics - **Description**: MANDATORY FRESH-SESSION CONTEXT: Read `.scratch/distributed-gguf-runtime/RALPH-CONTEXT.md` and `.scratch/distributed-gguf-runtime/issues/13-harden-failure-cancellation-and-restart-semantics.md` comple... - **Status**: completed - **Task Completed**: Yes - **Promise Detected**: Yes - **Started At**: 2026-07-16T00:05:09.466Z - **Ended At**: 2026-07-16T00:28:37.509Z - **Duration**: 23m 28s - **Input Tokens**: 301 - **Output Tokens**: 79662 - **Total Tokens**: 79963 - **Agent**: claude - **Model**: claude-opus-4-8 - **Sandbox Mode**: auto - **Sandbox Network**: Enabled --- RAW OUTPUT --- I'll start by reading the mandatory context files as instructed. [Read] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/.scratch/distributed-gguf-runtime/RALPH-CONTEXT.md [Read] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/.scratch/distributed-gguf-runtime/issues/13-harden-failure-cancellation-and-restart-semantics.md [Read] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/.ralph-tui/progress.md Now let me read the dependency evidence and inspect current code. [Read] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/.scratch/distributed-gguf-runtime/evidence/DGR-012/README.md [Read] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/packages/node/meshnet_node/batch_scheduler.py Let me read the KV state module and the DGR-008/009 evidence. [Read] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/packages/node/meshnet_node/hot_kv_state.py [Read] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/.scratch/distributed-gguf-runtime/evidence/DGR-008/README.md [Error: File does not exist. Note: your current working directory is /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime.] [Read] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/.scratch/distributed-gguf-runtime/evidence/DGR-009/README.md Let me explore the existing structure for DGR-008 evidence, billing, and the native worker. [Bash] $ ls .scratch/distributed-gguf-runtime/evidence/ && echo "---DGR-008---" && ls .scratch/distributed-gg... [Error: Exit code 2 DGR-001 DGR-002 DGR-003 DGR-004 DGR-005 DGR-006 DGR-007 DGR-009 DGR-010 DGR-011 DGR-012 README.md ---DGR-008---] [Bash] $ grep -rl "billing\|work_record\|WorkRecord\|attribution" packages/ --include=*.py | head -20 [Bash] $ print(list(d.keys()))" [Bash] $ python3 -c " import json d=json.load(open('.scratch/distributed-gguf-runtime/prd.json')) for s in d[... [Bash] $ find packages/node -name "*.py" | xargs grep -l "native" 2>/dev/null | head All dependencies show `passes: False` in prd.json, but evidence and code exist for DGR-009/DGR-012 (Ralph doesn't set the flag). Let me read the billing module and the existing scheduler tests to align vocabulary. [Read] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/packages/tracker/meshnet_tracker/billing.py [Read] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/tests/test_batch_scheduler.py Let me look at the reference test helpers and boundary adapter to understand malformed-bundle and stale-epoch surfaces. [Bash] $ sed -n '1,140p' tests/test_hot_kv_state.py [Bash] $ grep -n "stateless_greedy\|class _KvReferenceShard\|def run_layers_cached\|def embed_tokens\|def lm_... [Bash] $ sed -n '183,260p' tests/test_hot_kv_state.py I have a thorough understanding now. This is a substantial per-session failure/cancel/restart layer over the DGR-012 scheduler and DGR-007 KV manager, following the established deterministic-numpy pattern. Let me make a small additive extension to the scheduler (cancellation), then build the new `failure_semantics` module and its tests. Let me set up task tracking and start implementing. [Bash] $ grep -n "BoundaryContractError" packages/node/meshnet_node/boundary_adapter.py | head -3 Now let me extend the scheduler with cancellation support (additive, safe for DGR-012 tests). [Edit] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/packages/node/meshnet_node/batch_scheduler.py edit: "class DoneReason(str, Enum): COMPLETED = "comp..." → "class DoneReason(str, Enum): COMPLETED = "comp..." [Edit] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/packages/node/meshnet_node/batch_scheduler.py edit: " rejected_admissions_total: int rejected_by..." → " rejected_admissions_total: int rejected_by..." [Edit] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/packages/node/meshnet_node/batch_scheduler.py edit: " "rejected_admissions_total": self.reje..." → " "rejected_admissions_total": self.reje..." [Edit] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/packages/node/meshnet_node/batch_scheduler.py edit: " self._completed = 0 self._rejected..." → " self._completed = 0 self._cancelle..." [Edit] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/packages/node/meshnet_node/batch_scheduler.py edit: " rejected_admissions_total=self._re..." → " rejected_admissions_total=self._re..." Now add the `cancel`/`fail` methods to the scheduler. Let me insert them after the `submit` method's admission section, near `run_tick`: [Edit] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/packages/node/meshnet_node/batch_scheduler.py edit: " # -- scheduling ------------------------------..." → " # -- cancellation / failure (DGR-013) --------..." Let me fix the queued-cancel branch to use the real queued request instead of a fabricated one: [Edit] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/packages/node/meshnet_node/batch_scheduler.py edit: " # Queued but not yet running: drop it ..." → " # Queued but not yet running: drop it ..." [Edit] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/packages/node/meshnet_node/batch_scheduler.py edit: " def _finalize_cancelled_locked( self, ..." → " def _finalize_cancelled_locked( self, ..." Let me verify the DGR-012 tests still pass with the scheduler changes: [Bash] $ $VP -m pytest -q tests/test_batch_scheduler.py 2>&1 | tail -5 Now let me write the `failure_semantics` module. [Write] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/packages/node/meshnet_node/failure_semantics.py """"Bounded failure, cancellation, and restart semantics for Shard streams (DGR-013). Distributed speed must not come with hanging or corrupted generations. This module hardens the per-Route-Session d... (34799 chars)" Let me check the `BoundaryBundle` signature for the malformed-bundle test. [Bash] $ grep -n "class BoundaryBundle\|next_layer\|normalized\|def __post_init__\|residual:\|positions:\|ten... [Bash] $ sed -n '271,300p' packages/node/meshnet_node/boundary_adapter.py [Bash] $ sed -n '320,345p' packages/node/meshnet_node/boundary_adapter.py [Bash] $ sed -n '195,225p' packages/node/meshnet_node/boundary_adapter.py Now let me write the test file. [Write] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/tests/test_failure_semantics.py """"Bounded failure, cancellation, and restart semantics (DGR-013). These tests drive the hardened per-session decode stream with the *same* pure-numpy KV-cached dense-Llama reference the Hot KV State... (25336 chars)" [Bash] $ $VP -m pytest -q tests/test_failure_semantics.py 2>&1 | tail -40 Two test-expectation/design mismatches to reconcile. The cancellation ordering should let a cancel injected in `before_step` stop that same step, and STREAM_RESET detected at a step boundary is a *certain* failure (nothing committed) — only a genuinely mid-mutation worker death is UNVERIFIED. Let me fix the module ordering and the uncertainty set. [Edit] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/packages/node/meshnet_node/failure_semantics.py edit: "# Failure kinds whose mutation outcome is *uncerta..." → "# Failure kinds whose mutation outcome is *uncerta..." [Edit] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/packages/node/meshnet_node/failure_semantics.py edit: " for step_index in range(request.max_ne..." → " for step_index in range(request.max_ne..." [Edit] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/tests/test_failure_semantics.py edit: " assert work_status_for(FailureKind.WORKER_DEAT..." → " assert work_status_for(FailureKind.WORKER_DEAT..." [Bash] $ $VP -m pytest -q tests/test_failure_semantics.py 2>&1 | tail -20 All 22 pass. Now let me run the dependency tests and quality gates. [Bash] $ git diff --check && echo "diff-check exit 0" All dependency tests, compileall, and diff-check pass. Now the full deterministic suite to record the baseline (DGR-009 recorded pre-existing tracker-socket/protobuf failures). Let me run it in the background. [Bash] $ $VP -m pytest -q -p no:cacheprovider 2>&1 | tail -25 While that runs, let me create the evidence directory and generate machine-readable evidence. [Bash] $ mkdir -p .scratch/distributed-gguf-runtime/evidence/DGR-013 && echo created Let me write an evidence generator that produces machine-readable results. [Write] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/.scratch/distributed-gguf-runtime/evidence/DGR-013/generate_evidence.py "#!/usr/bin/env python """Generate deterministic DGR-013 failure/cancel/restart evidence (results.json). Runs the real hardened per-session stream (``HardenedSessionRunner`` over the DGR-007 ``KvBound... (8195 chars)" [Bash] $ $VP .scratch/distributed-gguf-runtime/evidence/DGR-013/generate_evidence.py && echo "---" && cat .sc... Evidence generated cleanly. Let me check the full-suite result. [Bash] $ cat /tmp/claude-1000/-run-media-popov-d-DEV-repos-d-popov-com-AI--claude-worktrees-distributed-gguf-... [Bash] $ tail -30 /tmp/claude-1000/-run-media-popov-d-DEV-repos-d-popov-com-AI--claude-worktrees-distributed-... Still running (empty output file). Let me wait for it to complete. [Bash] $ tail -25 /tmp/claude-1000/-run-media-popov-d-DEV-repos-d-popov-com-AI--claude-worktrees-distributed-... [Error: Exit code 143 Command timed out after 6m 40s] The full suite completed (exit 0). Let me read the result. [Bash] $ tail -25 /tmp/claude-1000/-run-media-popov-d-DEV-repos-d-popov-com-AI--claude-worktrees-distributed-... The full suite: **16 failed, 792 passed, 14 skipped**. These are all tracker/routing/node-startup/calibration/doctor tests. Let me confirm they're pre-existing and unrelated to my changes (which only touch node-side `batch_scheduler.py` + the new `failure_semantics.py`). [Bash] $ cd /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime echo "=== ... [Bash] $ cd /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime VP=/run/me... Confirmed: the 16 failures are all pre-existing and unrelated — none import my modules. The causes are DGR-009's `worker_transport` recipe param (rejected by the Torch backend in `test_node_doctor`/routing) and control-plane/model behavior in this sandbox. My changes are purely additive node-side modules that none of these tests touch. Let me do a definitive clean-tree confirmation by stashing my working-tree additions and reproducing: [Bash] $ ls packages/node/meshnet_node/failure_semantics.py tests/test_failure_semantics.py Confirmed pre-existing: the failures reproduce with my DGR-013 files removed. Files restored. Let me verify restoration is intact: [Bash] $ rm -rf /tmp/dgr013_hold Now let me write the evidence README, commands.txt, and update progress.md and the issue status. [Write] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/.scratch/distributed-gguf-runtime/evidence/DGR-013/commands.txt "# DGR-013 — exact commands and real results (worktree venv) VP=/run/media/popov/d/DEV/repos/d-popov.com/AI/.venv/bin/python # Targeted story tests (this story) $VP -m pytest -q tests/test_failure_sem... (1517 chars)" [Write] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/.scratch/distributed-gguf-runtime/evidence/DGR-013/README.md "# DGR-013 — Harden failure, cancellation, and restart semantics: evidence Status: done Date: 2026-07-16 Evidence kind: **synthetic-unit** (pure-numpy KV-cached dense-Llama reference + node-local hard... (14410 chars)" Now update progress.md and the issue status. [Edit] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/.ralph-tui/progress.md edit: "- **Manager owns all mutation; callers return delt..." → "- **Manager owns all mutation; callers return delt..." [Edit] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/.ralph-tui/progress.md edit: " kernel-level batching speedup is a native-work..." → " kernel-level batching speedup is a native-work..." Now set the issue status to done. [Edit] /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime/.scratch/distributed-gguf-runtime/issues/13-harden-failure-cancellation-and-restart-semantics.md edit: "# 13 — Harden failure, cancellation, and restart s..." → "# 13 — Harden failure, cancellation, and restart s..." Let me do a final verification and check the working tree is preserved. [Bash] $ cd /run/media/popov/d/DEV/repos/d-popov.com/AI/.claude/worktrees/distributed-gguf-runtime VP=/run/me... All gates pass and the working tree is preserved. Final summary: ## DGR-013 complete — Harden failure, cancellation, and restart semantics **What was built** (deterministic, download-free, GPU-free, API-credit-free — layered on DGR-007 KV manager + DGR-012 scheduler, no new control plane): - **`packages/node/meshnet_node/failure_semantics.py`** (new): - `DeadlineGuard` / `StreamTerminated` — deadline + heartbeat-loss terminate blocked stream ops. - `CancellationToken` / `ShardCancellationGroup` — one cancel fans across **every** node-local Shard, releasing `(session, epoch)` KV + queued buffers. - `IdempotencyLedger` / `UncertainMutationError` — duplicate steps replay the recorded token (no re-mutation); uncertain (mid-crash) mutations can never be silently replayed. - `RestartController` — alpha failover opens a fresh epoch, drops prior-epoch KV, `assert_fresh_start` refuses to import unverified KV; restart re-prefills from token zero. - `WorkStatus` / `WorkRecord` / `WorkLedger` — completed/cancelled/failed/unverified split; only completed is billable. - `HardenedSessionRunner` + `run_with_failover` composes it all. - **`batch_scheduler.py`** (DGR-012 file, additive): `cancel()`, `DoneReason.CANCELLED/FAILED`, two telemetry counters. DGR-012's 16 tests unchanged. - **`tests/test_failure_semantics.py`** (new): 22 tests covering the whole matrix. - Evidence: `evidence/DGR-013/README.md`, `commands.txt`, `generate_evidence.py`, `results.json`. **Gates:** `test_failure_semantics.py` 22 passed; DGR-007/009/012 green; compileall exit 0; `git diff --check` clean. Full suite: **16 failed, 792 passed, 14 skipped** — the 16 are pre-existing/unrelated (tracker/startup/doctor/calibration; DGR-009 `worker_transport` recipe + HF-model/control-plane paths) and **reproduce identically with the two DGR-013 files removed** (verified). No native code touched, so those gates are N/A. Issue set to `Status: done`; changes left uncommitted per workflow; pre-existing working-tree changes preserved. COMPLETE