A daemon killed by the watchdog left its FUSE mounts dead. A dead mount
answers ENOTCONN, which create_dir_all took for an absent directory, so
every restart failed with EEXIST and retried forever without reaching the
code that clears stale mounts. mount_once now goes through
prepare_mountpoint, which clears a dead mount first.
Startup on a large account (70 s hydrating 48k nodes) plus the supervisor's
first ping one full period later outlasted WatchdogSec=120, so a restart
that did mount was aborted again. The daemon now asks for a 10-minute
watchdog before startup, the supervisor pings on its first tick, and the
unit's own timeout is restored once the control socket answers.
Records B279.
One thread runs every synced folder's passes. A panic in a pass ended
it, and every later add, sync-now, file event and poll went nowhere
without a word until a restart, which fits issue #53 (B259).
Each pass now runs under catch_unwind; a panic sets the folder to error
and the next poll tries again. Diagnostics reports the engine's state,
the supervisor warns when it has ended or a pass has gone quiet, and
first passes log at info.
A supervisor thread ticks every 15 s and does three things: it WARNs
about a worker that has held one job for two minutes, a control request
that never returned, or a lane that has not completed anything while its
queue is non-empty; it samples resident size and the pending-op count
into the log every five minutes; and it answers the systemd watchdog.
The watchdog ping is deliberately not a heartbeat from a thread that
does nothing else — that would keep the unit "healthy" through exactly
the hang it is meant to catch. It goes out only after a real round trip
over the control socket, so it means "a client can still talk to this
daemon", which is the property that failed on 2026-09-18.
`sd_notify` is spoken directly rather than through libsystemd (READY,
WATCHDOG, STOPPING), including the abstract-namespace address; off
systemd every call is a no-op.
The unit gains `NotifyAccess=all` (rather than `Type=notify`, which
would fail the unit on the start timeout when no login is stored yet),
`WatchdogSec=120`, `Restart=always` — a hang is not a failing exit code
— and `MemoryHigh`/`MemoryMax` as a backstop against the 5.2 G growth
the hung run showed.
nvrl