bug-1433: raft_cb_become_leader runs synchronously off peer_ctrl_dispatch_to_pool,
which hardcodes VTASK_LIVENESS for every inbound peer-control packet including
vote replies. The bug-1431 round-2 fix (flusher_flush_once force-flush in
persist_promotion_advance_committed) was reachable from that never-blocks task
class -- same bug family as bug-1198. Removed the force-flush; round-3
(durable-capped only) plus the already-shipped bug-1432 immediate-first-heartbeat
fix close the visibility-latency gap non-blockingly. TRACKED RESIDUAL:
persist_apply_pump_run_sync is still reachable on the same VTASK_LIVENESS path
and does bounded pread() -- lower risk (page-cache-hot) but strictly still
blocking I/O; not safe to remove outright (reopens bug-1043-family job loss),
needs its own follow-up (reclassify peer_ctrl_classify's winning-vote-reply case
or dispatch promotion tail onto a fresh VTASK_LIVE_BLOCK vtask).
bug-1434: persist_promotion_advance_committed and ha_standby_advance_committed_and_apply
raced on persist_t.committed_lsn via an unlocked load-then-conditional-store during
the promotion window (before ha->role flips to CTRL_PRIMARY) -- a losing racer could
regress committed_lsn. Added persist_committed_lsn_advance_atomic (CAS retry loop,
lock-free) and routed both call sites through it.
Validated: 19/19 unit test suites, 6-round chaotic soak (0 loss/divergence) + 6-round
sequential+leadership-coverage soak, both PASS. Also folds in raft-apply-decoupling
and raft-ha-core-safety validate-impl phase bumps to "implemented" and clears
config-upgrade-snapshot's now-satisfied entity-bearing-snapshots block.
Wire persist_apply_pump_run() to call persist_take_pending_apply()
immediately after each entry's apply_committed_entry() call,
invoking the registered continuation strictly after the mutation.
Adds jobsubmit_reply_success_once() (job.c) so a successful job
submission finally sends a client reply once every array element
applies -- closes the standing gap from task 3.2 where committed
submissions never got a response.
Fixes bug-1415: commit_resolve_pending() dispatches the commit
continuation and the apply-pump kick as two independent
VTASK_LIVE_BLOCK vtasks with no completion-order guarantee. On any
real multi-vcpu pool (the production default, n_vcpus=8), if the
apply pump won the race and advanced last_applied_lsn past an LSN
before its continuation registered, the registration was permanently
orphaned -- the job would be constructed and visible, but the client
would hang forever. Untested by every existing fixture in this spec
(all use pool=NULL, which trivially serializes and can't reproduce
the race).
Fixed with a self-healing check in persist_register_pending_apply():
if the LSN is already <= last_applied_lsn, invoke the callback
immediately instead of registering for later pickup. Verified by the
spec's first genuine multi-vcpu regression test (real vtaskmgr_t,
n_vcpus=4), independently RED->GREEN reproduced by two review rounds.
Build persist_apply_pump_run()/persist_apply_pump_kick() -- the
ordered walk from last_applied_lsn+1 through committed_lsn, applying
every entry via apply_committed_entry() regardless of commit mode.
This is the first live (non-replay) consumer of that dispatch
function. Kick is wired into commit_resolve_pending() (the single
choke point all 6 internal committed_lsn-advancing paths funnel
through, discovered in task 1.2), dispatched via
vtask_enq_classified(VTASK_LIVE_BLOCK) with a CAS-coalesced
fire-and-forget trigger.
Fixes the two hazards flagged since task 4.1 as required before
going live:
1. Double-append: a thread-local call-provenance guard
(t_apply_seam_notifying) prevents persist_job_hook_fun/
persist_queue_hook_fun/persist_worker_hook_fun from re-appending
entries the apply pump itself just applied, while preserving
job_ctrl's legitimate live command-path appends (a naive
detail-based filter would have broken SIGCONT/SIGSTOP). Also
closes an undocumented instance of the same hazard in the
queue/worker hook functions.
2. Merge-staleness: record_job_fail_fact/postdone's fact recording
previously baked a receipt-time-computed final job state into the
WAL entry, which goes stale under deferred apply -- a FINISH
followed shortly by an ordinary post-exec FAIL could silently
clobber a correct DONE completion with a stale RUN|EXIT|PERR, no
guard catching it. Fixed by repurposing wal_jobstate_t's unused
_pad field to carry just enough data (FAIL's stage) to recompute
against the job's actual current state at apply time via the real
apply_job_fail_transition()/new apply_job_postdone_transition()
guard cores, instead of overwriting with a stale absolute value.
Backward compatible: _pad==0 (all prior data) routes to the same
legacy overwrite behavior.
Also fixes bug-1409 (unbounded busy-loop in apply_pump_drain when
committed_lsn advances without a corresponding on-disk entry) and a
genuine test-flakiness hazard (a second, independent apply-pump
kicker from the fsync_worker thread that existing tests didn't
account for).
Two pre-existing tests in test_commit_barrier_reply.c now fail as
expected -- their own assertions state "no job may be constructed
until task 6's apply pump exists," now correctly invalidated by this
task landing; updating them is task 7.3's explicit job.
