Chaotic election churn (config-upgrade-snapshot task 8.6's force_elect_node
rotation) can leave a standby log-conflicted after a rejoin. Fixing this
needed three compounding layers, each unit-green but still failing the
identical live scenario until the next layer landed:
1. ha_raft_on_repl_nack (ha.c/ha.h): routes a WAL-ACK NACK into the raft
library's nextIndex backoff and immediately repl_start_catchup's the
standby at the corrected position, instead of the 16-strike silent
eviction with no catch-up driver after it. Correct from the start, but
live soak still failed identically: nothing ever produced the NACK this
code was waiting for.
2. Standby-side NACK sending: ha_apply_term_entry_via_library's logOk-reject
path now calls a new ha_send_wal_ack_reply_ex(..., success=0) instead of
silently dropping the reject. ha_send_wal_ack_reply had hardcoded
success=1 unconditionally -- the only WalAckReply sender in the
controller -- making (1)'s NACK-routing correct but unreachable dead
code. New ha_wal_ack_send_hook (XCE_TESTING) lets a unit test observe
the NACK without a live endpoint. Live-confirmed the NACK now reaches
the primary -- but the scenario still failed for a third reason.
3. ha_compute_repl_stream_ceiling_lsn (ha.c/ha.h): ha_stream_wal_to_standby's
catch-up range was hard-bounded at committed_lsn, which can never advance
in this exact scenario because advancing it requires an ACK from the very
standby that's stuck catching up (2-of-3 alive, this standby is the only
path to a new majority) -- a self-referential deadlock. Widens the
STREAM_WAL ceiling (and the convergence check gating it) to the leader's
own log tail, matching raft.tla's real AppendEntries semantics
(leaderCommit is advisory, never a send-cap), while reusing bug-1478's
exact guard so this doesn't reopen that trap (never widen onto a trailing
local-only checkpoint's own unstreamable LSN).
Verification: controller_unit_test 1053/1053 PASS, clean twice, including
new regression tests for all three layers (test_config_repl.c,
test_term_safety_adapter.c, test_ha_role.c), each RED-confirmed against its
pre-fix behavior before the real fix was restored. Three successive live
run-ha-soak.sh --config-upgrade re-runs tracked each layer landing; the
final run passed end-to-end -- all 3 force_elect_node rounds succeeded
(ctrl-2: 3/3 jobs acked term=6; ctrl-3: 3/3 jobs acked term=7, never
previously reached), zero materialized-state divergence, zero job loss.
Unblocks config-upgrade-snapshot task 8.6.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Only 21 of 86 test_*.c group functions called their own nested
UNITY_BEGIN()/UNITY_END(). Each nested call reset Unity's global
NumberOfTests/TestFailures counters, so controller_test.c's final
`return UNITY_END();` -- the value meson test actually gates on --
only ever reflected whichever small window of tests ran since the
LAST nested reset, silently discarding pass/fail evidence for
everything before it (measured: 16 of 972 total tests in one run).
The same nested-BEGIN calls also caused PASS/FAIL banners to show
the wrong source file for tests in files that don't reset it
themselves (Unity.TestFile just carries over from whichever group
last called UNITY_BEGIN()).
Fix: replace every nested UNITY_BEGIN() with UnitySetTestFile(__FILE__)
(sets file attribution only, no counter reset) and drop the matching
UNITY_END(); add the same UnitySetTestFile(__FILE__) as the first
statement to the other group functions that had neither. The 2
genuinely standalone binaries (test_job_array_sched_push.c,
test_job_array_apiserver_push.c -- each has its own int main(), not
registered via controller_test.c's TEST() macro) are untouched.
Verified: single consolidated summary now reads
"972 Tests 0 Failures 0 Ignored OK", exactly matching the
ground-truth RUN_TEST call-site count across all 83 registered
group files (976 total minus 4 belonging to the 2 standalone
binaries). Every PASS/FAIL banner now names its own true source
file. Full xce-build.sh all regression pass clean (Ok: 9, Fail: 0).
No production code touched -- test-harness plumbing only.
Two coupled fixes for a live commit-stall (committed_lsn pinned at the own-term
NOOP while a 3-node cluster was durable to LSN 5 — jobs acked but never committed):
bug-991: the WAL catch-up applied_lsn was advanced to lsn+1 (next-to-apply) in
the three live/catch-up apply paths, but recovery/checkpoint/init and the leader's
catch-up streamer treat it as last-held. The over-advertise made the streamer skip
an LSN -> library logOk wedge -> no WalAck. Fixed to last-held (= lsn).
Option A (design reconsideration of REVIEW ISSUE 3): removed the
committed = min(durable-majority, raft_commit_index) ceiling. Under single-writer
the durable-majority watermark is already (term,lsn)-current-term-safe (term-carrying
replication + (term,lsn) reconcile/truncate-before-durable + own-term NOOP gate +
post-election truncate-to-safe), so the library commit_index was a redundant,
starvation-prone gate that pinned committed below the safe durable majority whenever
the library lagged. The durable-majority barrier + own-term writable gate are now
authoritative; raft_commit_index is inert-advisory.
Safety: reviewer-verified the durable-majority watermark is (term,lsn)-safe and
Figure-8 holds via the own-term gate (new RED->GREEN test); bug-851 cannot recur.
Live: commit trace 4->5 + walcompare committed-prefix identical across 3 nodes.
177 unit tests pass.
Closes bug-990: the live replicator repl_broadcast wire-encoded term=0
(entry.term was never set), so standbys persisted hdr.term=0 and took the
legacy direct-apply path instead of the library (term,lsn) intake. Now the
live broadcast and catch-up streamer carry the leader's real term + AE prev
tuple; ha_apply_wal_catchup_entry routes every term-carrying entry through
raft_on_append_entries_request -> on_persist_entry (leader term stamped),
retiring the term-0 direct-apply. Standbys now persist the leader's real term
and reconcile by (term,lsn); the live commit chain is end-to-end.
848/849/850 + persist-before-ACK + commit-barrier + bug-960 preserved.
Proven at integration level; the definitive live STRICT_TERM failover run is
env-blocked here (bug-924 overlayfs) and recommended on a real fs.
Includes fix for bug-960: endpoint-type-aware peer-index resolution
(promoted-vote relative vs heartbeat-standby absolute) with fail-loud
bounds check, preventing an out-of-bounds match_index[] write / wrong-peer
false-quorum on the replication ACK path.
Replaces the stub: builds a WalCatchupEntry AppendEntries to standbys[peer_idx].ep
carrying prev_log_index/prev_log_term; for n_entries==1 sources the entry at
prev_log_index+1 from the local WAL (term via persist_entry_term, type+payload via
ha_read_wal_entry_at); n_entries==0 emits a zero-entry heartbeat. Async send
(xce_wal_batch_req_raw), payload freed on all paths. 2 tests via a capture seam.
Review-applied: corrected the misleading repl.c comment — leader_commit is accepted
but NOT yet wire-encoded (deferred to task 3.2: WalCatchupEntry leaderCommit field +
standby intake). Reviewer APPROVED; per-group 0 failures.
on_get_entry_term → persist_entry_term (recorded term, 0=absent, legacy-0→1; caveat
documented per 1.3 review). on_truncate_from → persist_truncate_wal_above(p, index-1)
(delete LSN>=index), returns rc for library/leader retry; non-promotable fence intact;
replaces the committed-boundary heuristic on the library-driven path. New
truncate_term_index_locked keeps the in-memory per-LSN term index consistent on both
truncate paths (under lock, cutoff-aligned) → no stale-term read after truncation.
3 tests, reviewer APPROVED, per-group 0 failures.
Replaces the iter-1 stub: persist_set_term(p, term) stamps the leader/library term
into hdr.term, then role-routes the write — primary via persist_wal_async, standby
via persist_wal_write_replicated(p, index, ...). Persist failure returns non-zero
(no false ACK; durable_lsn unchanged); bug-850 contiguity guard + persist-before-ACK
preserved beneath. In-flight raft_entry_blob_t {type,payload_len} envelope added to
wal_types.h (never enters the 40-byte header). 3 tests, reviewer APPROVED.
Deferred (recorded in tasks.md): task 3.1 must retire the hand-rolled primary append
so current_lsn tracks the library index; task 3.2 must not call on_persist_entry on
heartbeats. Per-group 0 failures (pre-existing test_commit_barrier_reply leak aside).
persist_set_term sets the live election term so appends stamp hdr.term (fixes the
G1 term-0 stamping); replay_wal builds an in-memory per-LSN term index (freed in
persist_fini, no on-disk change); persist_entry_term reads it back (0=absent).
Legacy-0 -> WAL_LEGACY_TERM=1 at read-back only (raw 0 retained so present-legacy-0
is distinguishable from absent). 40-byte wal_entry_hdr_t preserved (value fix, R1.7).
5 new tests (test_term_safety_adapter.c); reviewer APPROVED. Feeds task 2.2.
All controller test groups report 0 failures; the meson full-suite timeout is the
bug-924 overlayfs /tmp fdatasync artifact, not this task.
