myxce/.wolf/bugs/bug-1433.md
Rongsong Shen d26ff8870d
feat(buglog): one Markdown record per bug, checked against a record standard
The buglog was one 27K-line JSON file whose fields covered only symptom,
root cause and fix, as free text: 2% of entries named the code version a
bug was found on, 12% the build profile, 36% a way to reproduce, and 58% of
the file was OpenWolf hook auto-detections ("Missing guard clause",
"Function not marked async" on .md files).

- .claude/skills/buglog/bug-record.md: the record standard. Eight
  sections (Summary as the title, Description, Environment, Reproduction;
  Root cause, Fix, Verification, References once fixed), each with the
  content it must contain -- e.g. Environment needs the OS, the libc the
  failing binary loads (from its ELF interpreter: glibc 2.42 in the nix
  shell vs 2.40 on the host), toolchain, build profile and commit.
- .wolf/bugs/<id>.md: 500 records migrated from buglog.json; every field
  verified to round-trip. They carry legacy: true and an explicit "not
  recorded" where the old log had no such field; component derived from
  file paths, severity from keywords (else unknown), fix_commits from
  hashes in status_note/fix that git resolves (91 of 463 fixed).
- .wolf/buglog-archive.json: the 710 hook auto-detections, verbatim.
- .wolf/buglog.json is now an index generated from the records, keeping
  the fields OpenWolf's hooks and `openwolf bug search` read.
- scripts/buglog.py rewritten: new (template + Environment collected from
  the machine and --binary), check, status (refuses a status the record
  doesn't support; fixed needs Root cause, Fix, Verification and
  --commit hashes git resolves), note, recur, set, show, list, triage,
  env, index. 29 unittest cases in scripts/tests/test_buglog.py.
- scripts/git-hooks/pre-commit runs `check --staged`: incomplete staged
  records, a legacy record hand-changed to fixed without the fix-time
  sections, a new record claiming legacy: true, or a stale index refuse
  the commit.
- scripts/gitea-sync.py reads the records: issue body = the record's
  sections plus linked fix commits (origin remote, GITEA_COMMIT_REPO to
  override), and a body hash so an issue's text is refreshed when the
  record changes.
- bug-1866 rewritten to the full standard as the worked example.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
2026-09-28 03:40:11 +00:00

3.5 KiB

id status status_updated status_note component severity timestamp last_seen occurrences files tags related fix_commits legacy
bug-1433 fixed 2026-09-27 255b0faa: peer-control traffic while CTRL_ELECTING classified VTASK_LIVE_BLOCK (become-leader tail preads) controller unknown 2026-07-10T10:59:00Z 2026-09-19T09:00:00Z 1
src/controller/persist.c
src/controller/ha.c
raft
promotion
vtask
thread-role
liveness
audit-finding
bug-1198-class
bug-1431
bug-1432
bug-1198
255b0faa
true

bug-1433: controller-invariant-audit (2026-07-10, /xce-audit-invariants) async-I/O-thread-role dimension…

Description

controller-invariant-audit (2026-07-10, /xce-audit-invariants) async-I/O-thread-role dimension: bug-1431 round-2 force-flush fix (persist_promotion_advance_committed calling flusher_flush_once, a blocking fdatasync) is reachable via the real multi-node winning-vote-reply dispatch path on a VTASK_LIVENESS-classified vtask worker -- a task class the design documents as never admission-gated / never expected to block. This is the same bug class as bug-1198 (HA_REPL_SEND_SNAPSHOT persist_checkpoint on VTASK_LIVENESS), which was previously closed by offloading the blocking work off that worker class entirely.

Environment

Not recorded (migrated from buglog.json).

Reproduction

Not recorded (migrated from buglog.json).

Root cause

raft_cb_become_leader (the .on_become_leader raft-library callback) is invoked synchronously from within peer_ctrl_msg_handler -> peer_ctrl_dispatch_to_pool -> peer_ctrl_classify (ha.c ~5935-5940), which HARDCODES VTASK_LIVENESS for every inbound peer-control packet including vote replies -- the doc comment above it explicitly states "everything this handler dispatches is liveness work today" and was written BEFORE this session added a blocking fdatasync call reachable from that same path. ha_dispatch_election_start/raft_election_start_vtask_entry (the VTASK_LIVE_BLOCK dispatch used for the RDHUP-failover and single-node self-grant election-START triggers) does NOT cover the separate, later "win the election / become leader" event, which fires on vote-REPLY arrival via a completely different dispatch chain.

Fix

Removed the flusher_flush_once force-flush from persist_promotion_advance_committed entirely -- round-3 (durable-capped only, no blocking calls) plus the already-shipped bug-1432 immediate-first-heartbeat fix together close the original visibility-latency gap non-blockingly (confirmed by two live soaks: 6-round chaotic committed_job_loss=0/committed_divergence=0 PASS, 6-round sequential+leadership-coverage PASS). TRACKED RESIDUAL (not fixed this session): persist_apply_pump_run_sync (added earlier this session for the bug-1043-family apply-lag fix, also called from raft_cb_become_leader on the same VTASK_LIVENESS path) does bounded pread() of recently-written WAL segments -- lower practical risk than fdatasync (almost always page-cache-hot) but still, strictly, blocking I/O on a never-blocks task class. Removing it is NOT safe (reopens bug-1043-family job loss). Proper fix needs either reclassifying the winning-vote-reply case in peer_ctrl_classify or dispatching promotion tail onto a fresh VTASK_LIVE_BLOCK vtask -- both larger changes deferred to a dedicated follow-up with its own soak-validation pass. Comments at both call sites corrected to stop falsely claiming VTASK_LIVE_BLOCK safety.

Verification

Not recorded (migrated from buglog.json).

References

  • Related: bug-1431, bug-1432, bug-1198