I have a bad problem with some n3-line-charts and Habpanel.
I suspect it might be related with the MySQL server but I can’t figure out how.
What I have:
OH2.1 on an Orange Pi Zero with MySQL persistence using the MySQL server of a Drobo 5N NAS.
A series of Habpanel dashboards used for different rooms and some showing n3-line-charts of weather, indoor climate and energy consumption data. Some of them pull quite a few (about 12000) datapoints
What’s changed recently:
Until some days ago the persistence was on a local MySQL database stored on a flash drive. That was fairly unreliable and required frequent intervention. So instead of running my own, I added a database for openhab to the preexisting MySQL service of a Drobo 5N NAS on my network. That works like a charm - most of the time.
I also changed the way some of my persisted values are treated by rules, but I’ve not changed the charts, the format or quantity of data used, so I think that’s not related.
What goes wrong:
After some heavier chart use, e.g. opening the dashboard with the 12000 datapoint charts a few times, charts stop working altogether:
Other habpanel dashboards still work, but the ones containing charts just show blank chart axis.
I can also not edit the non-working dashboards anymore - clicking the pencil next to the dashboard name does nothing.
In the Karaf console I see nothing get logged with relation to Habpanel or MySQL, neither Info nor Warnings. MySQL persistence continues to receive data normally for my items. Only thing I see logged is the HABpanel stopped/started message if I edit one of the still functional dashboards.
Doing this does not restore the charts.
If however I restart OpenHAB2 completely, things will return to normal, charts show and dashboards can all be edited.
Does anybody have ideas what could be going on?
Shouldn’t I see errors if there’s something wrong querying the database? And how can HABpanel fail so seriously without logging anything?