Gateway, dashboard, ACP server and the CLI already hold one registry-shared
SessionDB per state.db path, yet several in-process call paths still opened
a bare SessionDB() beside it. Each one is a full writer: schema init, write
lock, token-writer thread and a close-time WAL checkpoint. On a dashboard
serving overlapping requests that stacked up to the "5 live SessionDB
handles" precursor within seconds; per #110544 they are now harmless to each
other's WAL generation, but the leak itself remained.
Pure readers attach read_only=True (no writer connection, no write lock):
- plugins/hermes-achievements/dashboard/plugin_api.py::scan_sessions
(dashboard, per background scan and per /rescan; highest-frequency site)
- hermes_cli/console_engine.py::_session_db (dashboard console; list,
stats and export are reads; rename/optimize opt in to a writer)
- tools/process_registry_results.py::_owns_result (gateway, per retained
result load)
- hermes_cli/main.py::_session_db (last-session / title / cwd lookups)
- hermes_cli/terminal_breadcrumbs.py, hermes_cli/status.py,
hermes_cli/main_tui_launch.py (lookup one-shots)
Writers share the process's registry handle (hermes_state_registry.acquire;
close()/release_or_close release one refcount):
- acp_adapter/session.py::SessionManager._get_db — the AIAgent it builds
acquires the same path, so the ACP server held two writers per process
- hermes_cli/kanban_db_dispatch.py::_retag_legacy_worker_sessions
(gateway dispatcher tick)
- hermes_cli/main.py::_create_titled_session, hermes_cli/oneshot.py,
hermes_cli/foreign_sessions.py — the CLI acquires the same handle a
moment later
The "N live SessionDB handles" warning now counts only writable members:
read-only attaches are the sanctioned per-request shape for dashboard
routers and CLI lookups, and counting them turned a healthy topology into
an operator alarm (#100896 field reports of restart loops keyed on it).
Live repro (one registry writer + 4 overlapping dashboard/gateway paths in
one process): before 5 writable opens, 5 live handles, warning fired;
after 1 writable open (the registry handle), 0 from the request paths,
no warning.
Refs #100896#103339
939a2f64b4