@igi pointed me to a solution for that problem: OH has an integrated feature to filter the event log, see the discussion here
The configuration is added as a new section to
openhab2-userdata/etc/org.ops4j.pax.logging.cfg
Based on this you could use the following config:
# custom filtering rules
log4j2.appender.event.filter.uselessevents.type = RegexFilter
log4j2.appender.event.filter.uselessevents.regex = .*(heartBeat|LastUpdate|lastUpdate|LetzteAktualisierung|Uptime|Laufzeit|ZuletztGesehen).*
log4j2.appender.event.filter.uselessevents.onMatch = DENY
log4j2.appender.event.filter.uselessevents.onMisMatch = NEUTRAL
This filters events for items heartBeat, lastUpdate, LetzteAktualisierung, Uptime, Laufzeit, ZuletztGesehen. Replace those strings with the items you want to filter.
Please note: Once events are filtered they are “lost”, you can’t find them later.