solr: Alfresco Search Services 1.3.1 using Apache Solr 6.6.5
Every day the solr service stops working. The only message I was able to get in it's solr.log is "ERROR (qtp947679291-17) [ x:alfresco] o.a.s.h.RequestHandlerBase org.apache.lucene.util.automaton.TooComplexToDeterminizeException: Determinizing automaton with 15226 states and 30003 transitions would result in more than 10000 states."
"Running OOM killer script for process 2423 for Solr on port 8983 Killed process 2423"
The issue started last week, indexes has been rebuilt since then, no effect. What can cause this error?