Henrik Lemke
98d8e4a0c5
- docs/did_you_know/: one short tip per feature added since May 2026 (<date>-<slug>.md, YAML front matter: added/tags/details), listed newest first; index.md describes the format for adding more. - New pages for features that had none: launching, command_history, tab_completion, live_gui, tweak, scanning, status_server, channel_access, shared_files, schematic_panels. Wired into index.rst together with the existing queues page. - Fix archiver_stripchart/listening_monitor: the method is archiver.strip_plot (strip_chart does not exist on DataHub); document the per-device .strip_plot(). - NAMESPACE_MONITOR_FORMAT.md: scan monitoring is wired into Daq's scan callbacks since 2026-09-09. - scripts/eco-docs (+ -install-user-service): build the docs from an own clone and serve them over HTTP as user systemd units, rebuilt by a timer; a failed build never replaces the served site.
82 lines
3.2 KiB
Markdown
82 lines
3.2 KiB
Markdown
# The status server and per-scan namespace recording
|
|
|
|
Recording the state of the whole namespace (thousands of channels) used to be
|
|
done by every scanning session itself: slow, and incomplete wherever that
|
|
session had not initialized everything. The **status server** is one
|
|
long-running process that holds the fully initialized namespace and does this
|
|
work for every session. With it:
|
|
|
|
- `status.json` and `aliases.json` in each run's `aux` folder are complete,
|
|
because they come from the server's fully initialized namespace rather than
|
|
from whatever your session happened to touch.
|
|
- Each scan can record the **update history of every monitorable channel**
|
|
for its whole duration (`namespace_monitor.ixp.h5`), not just snapshots at
|
|
the start and the end.
|
|
- Taking those snapshots no longer makes the scan wait; the server writes and
|
|
uploads them in the background.
|
|
|
|
## Looking at and controlling the server
|
|
|
|
The server is available in the namespace as `status_server`:
|
|
|
|
```python
|
|
status_server # repr: health and recording settings
|
|
status_server.status() # colored health line, failed devices, recent requests
|
|
status_server.gui() # Qt status / reinit window
|
|
status_server.reinit() # re-initialize the components that failed
|
|
status_server.restart() # restart it, wherever it runs
|
|
```
|
|
|
|
From a shell, the `eco-status-server` script does the same and more:
|
|
|
|
```bash
|
|
eco-status-server status # query its /health
|
|
eco-status-server respawn -w # restart the real server over HTTP, from any host; -w waits until ready
|
|
eco-status-server logs -f
|
|
eco-status-server gui
|
|
```
|
|
|
|
`respawn` reaches the server wherever it actually runs, on any host and under
|
|
any account. `start` and `restart` refuse to create a second server on another
|
|
host while a healthy one is already running (`start -f` overrides). Two
|
|
servers would drift apart and disturb each other.
|
|
|
|
## Switching it off from your session
|
|
|
|
All of these can be changed live, without restarting the session:
|
|
|
|
```python
|
|
daq.use_running_status_server = False # master switch: back to local status/aliases
|
|
daq.scan_monitoring = False # keep the server, but skip the per-scan recording
|
|
```
|
|
|
|
To start a session without it at all, set `ECO_STATUS_SERVER=off` in the
|
|
environment first.
|
|
|
|
The per-scan recording is new. If it slows down scan starts, or warns at
|
|
every scan that monitoring failed, set `daq.scan_monitoring = False` and
|
|
report it.
|
|
|
|
## The per-scan recording: `namespace_monitor.ixp.h5`
|
|
|
|
```text
|
|
<pgroup>/res/run_data/daq/run<NNNN>/aux/namespace_monitor.ixp.h5
|
|
```
|
|
|
|
It holds one escape `ArrayTimestamps` per channel, grouped by the channel's
|
|
full dotted alias, with updates throttled to 10 Hz by default. It is
|
|
registered in the run's `scan_info_rel.json` under
|
|
`scan_parameters["monitors"]`, next to `aliases` and `status`. It can be
|
|
opened with escape:
|
|
|
|
```python
|
|
import escape
|
|
mon = escape.DataSet(results_file=".../aux/namespace_monitor.ixp.h5")
|
|
mon.bernina.mono.energy # nested by alias
|
|
```
|
|
|
|
The file only exists for runs taken with a status server; there is no local
|
|
fallback. Some channels can be missing, for example if they could not be
|
|
attached. The full format description is in
|
|
`eco/status_server/NAMESPACE_MONITOR_FORMAT.md` in the repository.
|