Root-caused via raft-ha-core-safety 5.10a investigation: schedule_checkpoint()
(persist.c) fires correctly once wal_record_count crosses its threshold, but
its delay_task()-scheduled checkpoint_task_fn never executed in a live
multi-node deployment -- confirmed live via temporary diagnostic logging
(wal_record_count=100 max=100 logged, but the task itself never ran).
Root cause: delay_task_t carried TWO incomparable time representations --
`nextrun` (wall-clock time_t seconds, used by delay_task()) and `nextrun_ts`
(CLOCK_MONOTONIC timespec, used by delay_task_ms()). task_cmp()'s mixed-type
fallback compared them directly: an ms-task's nextrun is always 0, a
seconds-task's nextrun is a real epoch value (e.g. 1785600123) -- so 0
always sorted "less than" any seconds-task, regardless of actual due time.
ordq (src/lib/ordq.c) keeps its queue as an ascending sorted linked list by
this comparator, and delay_worker() only ever inspects the list HEAD
(ordq_peek with no matchfn returns q->head immediately, no scanning). Since
cluster_t.delaymgr is shared with ha.c's ~10 recurring delay_task_ms() call
sites (heartbeats, election timers, RDHUP polling), the head was
structurally almost-always occupied by an ms-task -- any delay_task()
(seconds) caller sharing that delaymgr, including schedule_checkpoint's
checkpoint_task_fn, could be starved indefinitely.
Fix: eliminate the dual representation entirely. Every task -- whether
scheduled via delay_task() (seconds) or delay_task_ms() (milliseconds) --
now stores one flat uint64_t CLOCK_MONOTONIC millisecond deadline
(nextrun_ms). delay_task() becomes a thin seconds->ms wrapper around
delay_task_ms(). task_cmp() and task_due() collapse to a single integer
comparison; delay_worker()'s reschedule is a flat integer add (no more
tv_sec/tv_nsec carry arithmetic, no more is_ms_task branching). Net -42
lines. Live-verified: after this fix, a forced checkpoint round produces a
real installed snapshot file (previously: schedule_checkpoint fired but the
task silently never ran).
controller_unit_test: full 58-group sweep, 0 Failures, 0 ASAN reports
(before and after this change) -- no regression, including every
delaymgr-touching group (test_demotion_convergence, test_ha_start_election_async,
test_ha_core_safety, test_ha_startup, etc).
Add millisecond-granularity delay_task_ms() to delaymgr using
clock_gettime(CLOCK_MONOTONIC) for deadline computation. Extends
delay_task_t with nextrun_ts field; delay_worker distinguishes
ms-tasks from second-tasks via non-zero nextrun_ts. Backward
compatible with existing delay_task callers.
4 delay tests pass (2 new: tolerance and invalid-args).
Provides the timeout primitive for election and committing watchdogs.
- Rename `precision` field to `precision_ms` in delaymgr_t struct (delay.h)
- Replace `sleep(mgr->precision)` with `nanosleep()` for 10ms granularity (delay.c)
- Add `#include <time.h>` to delay.c (already in delay.h)
- Update delaymgr_init() to store precision_ms parameter
- Update all call sites: cluster.c (2→200ms), controller/testsuite/test.c (2→2000ms),
lib/testsuite/test_delay.c (1→1000ms)
- Add TDD test test_delaymgr_precision_ms_field verifying field exists and stores correctly
- delay_task() delay parameter remains in seconds; only sleep granularity changes
