A 3-node rehearsal (PostgreSQL + NATS + Garage) found two ways a crash
leaves work stuck:
Pool hangs. The PostgreSQL pool (deadpool) was built with no timeouts,
so a request waited for a free connection, and for one to be opened or
recycled, for as long as it took: forever when the server stopped
answering. MySQL's pool (mysql_async) has no wait timeout at all.
- PostgreSQL: wait 30 s (or the store's timeout if longer), create the
store's timeout or 15 s (it bounds the whole handshake, where
tokio-postgres's connect_timeout covers only the TCP connect), recycle
10 s. The pool config is now always set, not only with
poolMaxConnections.
- MySQL: every connection is taken through MysqlStore::conn(), which
gives up after 30 s.
- Both: TCP keepalive after 60 s idle, so a server that vanished
without closing the connection is noticed in minutes rather than the
two-hour system default.
The DataStore schema has no pool timeout settings, so these are fixed
defaults; the store's own timeout bounds connecting on PostgreSQL.
Task locks. A task lock lasted an hour, so after a hard crash the dead
node's tasks waited up to an hour and five minutes. The lock is now a
five-minute lease: while this node runs a task, the task manager renews
its lock every third of the lifetime (InMemoryStore::renew_lock, a
compare-and-set on the store backends and SET XX EX on Redis, which
leaves a lock that already expired alone). A killed node's tasks run
elsewhere within about five minutes plus the claim recheck. A task this
node holds isn't handed to a worker again by the scan.
store::pool_timeout (new): a local listener that accepts connections
and never answers plays a hung server; a PostgreSQL store with a 2 s
timeout returns an error in about 4 s, and a MySQL store in 30 s.
Without the timeouts both wait for good. store::task_locks gains a
task held for 1.5 lock lifetimes: its lease is still held, and released
when the task ends.
A cluster rehearsal (PostgreSQL + NATS) left index tasks pending well
past the one-hour task lock after the node that claimed them was stopped
or killed. The exact cause there isn't confirmed; this closes every path
found in the task manager that stretches a takeover past the lock, or
keeps a task claimed without running it:
- A graceful stop never released the locks it held, so every task the
node had claimed stayed blocked for an hour. The server now tracks the
locks it holds (common::ipc::TaskLocks) and, once the shutdown signal
arrives, stops claiming and releases them before exiting.
- A node that failed to claim a task (another node held it) set its own
local hold for a full lock lifetime from that scan. If the holder
claimed it just after the scan began, or ran on a clock ahead, that
hold ran out a moment before the lock did and was set for another
hour: two hours in all. Such claims are now tried again every five
minutes (a twelfth of the lock lifetime), and the task manager wakes
up for them: before, a node without a coordinator could sleep up to
five minutes past the recheck, or until something else woke it.
- A worker that panicked took its task type down on that node for good,
while the scan kept claiming that type's tasks and failing to hand them
over, re-taking each lock as it expired and so starving every other
node of them. Each batch now runs on a task of its own; a panic is
logged, the batch's locks are released and the worker carries on. A
failed hand-over releases the lock too.
- A claimed task the worker couldn't read, or found gone, kept its lock
for the hour. It is released.
- An IndexDocument task for a file (not indexed) returned no result,
which shifted every later result in the batch onto the wrong task in
update_tasks. It returns Ignored. Nothing queues such a task today.
The lock lifetime stays one hour; it now lives per server so the tests
can shorten it.
store::task_locks::task_lock_tests plays a second node by writing its
locks straight into the in-memory store: tasks it claimed and abandoned
run here once its locks expire, including locks that outlive this node's
view of them, and a graceful stop hands this node's locks back at once
and claims nothing more. It passes on RocksDB, SQLite and PostgreSQL.
With the old recheck it fails.
Upstream commit: 474dd0229cb20cf513036619781ed97bd8073c3f
Enterprise-only files removed or emptied: 63
Enterprise-only snippets removed: 117 in 50 files
Dangling module declarations removed: 5
Cargo edits turning enterprise off: 14
Verification: clean
Enterprise feature gates left for rebuilt features: 19 in 18 files
Produced by tools/fork/strip.py. The full report is in docs/fork/strip-reports/ on main.
jcoffey-dev