Just a short report about my upgrade experiences…
Environment: OpenHAB 1.8.3, mostly Homegear (Homematic BITCOS) devices, MQTT/Mosquitto for location, some sh-scripts for feading external values via cron into the REST-API of OpenHAB, Weather binding. Lots of heating rules for Homematic radiators… some rrd-graphs. All running on a Raspi-2.
Upgrade to 2.0.0 was not without hassles due to the usage of astro-action. I used the migration guide, which is very good! Had to change some rules to get rid of astro-action, so the addon-folder of OpenHAB2 did not require manual addons. Had to fix a few rules (syntax cleanup, imports). Problems with ntp-binding, so I switched to the OpenHAB2 bindings for NTP during the upgrade and ntp worked again, this was easy. All other bindings are still on OpenHAB1-compatibility level.
Upgrade to 2.1.0 again had a few small problems (wildcard imports in rules are deprecated, easy). Using only the classic-UI resulted in being hit by “Classic UI: escape HTML characters #3748”, the problem has been fixed, but is currently not yet included in the “stable” branch.
Observations regarding performance and Java version:
I have installed the Oracle Java JRE. The performance is acceptable, but generally OpenHAB2 feels slower (using the classic UI), especially the graphs. For testing I switched to the embedded Zulu Java engine, but I did not notice a visible performance improvement, so I stay with the Oracle JRE.
This is a personal experience, so your mileage may vary… Have fun!
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