Log message just prior to the message I posted in the initial post
[2016-10-27T13:48:38,855][WARN ][logstash.filters.grok ] Grok regexp threw exception {:exception=>"interrupted waiting for mutex: null", :backtrace=>["org/jruby/ext/thread/Mutex.java:94:in `lock'", "org/jruby/ext/thread/Mutex.java:147:in `synchronize'", "c:/java8/elk5/logstash-5.0.0/vendor/bundle/jruby/1.9/gems/logstash-filter-grok-3.2.3/lib/logstash/filters/grok/timeout_enforcer.rb:38:in `stop_thread_groking'", "c:/java8/elk5/logstash-5.0.0/vendor/bundle/jruby/1.9/gems/logstash-filter-grok-3.2.3/lib/logstash/filters/grok/timeout_enforcer.rb:23:in `grok_till_timeout'", "c:/java8/elk5/logstash-5.0.0/vendor/bundle/jruby/1.9/gems/logstash-filter-grok-3.2.3/lib/logstash/filters/grok/timeout_enforcer.rb:16:in `grok_till_timeout'", "c:/java8/elk5/logstash-5.0.0/vendor/bundle/jruby/1.9/gems/logstash-filter-grok-3.2.3/lib/logstash/filters/grok.rb:333:in `match_against_groks'", "org/jruby/RubyArray.java:1613:in `each'", "c:/java8/elk5/logstash-5.0.0/vendor/bundle/jruby/1.9/gems/logstash-filter-grok-3.2.3/lib/logstash/filters/grok.rb:330:in `match_against_groks'", "c:/java8/elk5/logstash-5.0.0/vendor/bundle/jruby/1.9/gems/logstash-filter-grok-3.2.3/lib/logstash/filters/grok.rb:319:in `match'", "c:/java8/elk5/logstash-5.0.0/vendor/bundle/jruby/1.9/gems/logstash-filter-grok-3.2.3/lib/logstash/filters/grok.rb:285:in `filter'", "org/jruby/RubyHash.java:1342:in `each'", "c:/java8/elk5/logstash-5.0.0/vendor/bundle/jruby/1.9/gems/logstash-filter-grok-3.2.3/lib/logstash/filters/grok.rb:284:in `filter'", "c:/java8/elk5/logstash-5.0.0/logstash-core/lib/logstash/filters/base.rb:156:in `multi_filter'", "org/jruby/RubyArray.java:1613:in `each'", "c:/java8/elk5/logstash-5.0.0/logstash-core/lib/logstash/filters/base.rb:153:in `multi_filter'", "c:/java8/elk5/logstash-5.0.0/logstash-core/lib/logstash/filter_delegator.rb:41:in `multi_filter'", "(eval):8757:in `initialize'", "org/jruby/RubyArray.java:1613:in `each'", "(eval):8754:in `initialize'", "org/jruby/RubyProc.java:281:in `call'", "(eval):2889:in `filter_func'", "c:/java8/elk5/logstash-5.0.0/logstash-core/lib/logstash/pipeline.rb:260:in `filter_batch'", "org/jruby/RubyProc.java:281:in `call'", "c:/java8/elk5/logstash-5.0.0/logstash-core/lib/logstash/util/wrapped_synchronous_queue.rb:186:in `each'", "org/jruby/RubyHash.java:1342:in `each'", "c:/java8/elk5/logstash-5.0.0/logstash-core/lib/logstash/util/wrapped_synchronous_queue.rb:185:in `each'", "c:/java8/elk5/logstash-5.0.0/logstash-core/lib/logstash/pipeline.rb:258:in `filter_batch'", "c:/java8/elk5/logstash-5.0.0/logstash-core/lib/logstash/pipeline.rb:246:in `worker_loop'", "c:/java8/elk5/logstash-5.0.0/logstash-core/lib/logstash/pipeline.rb:225:in `start_workers'"], :class=>"ConcurrencyError"}
[2016-10-27T13:48:38,860][ERROR][logstash.pipeline ] Exception in pipelineworker, the pipeline stopped processing new events, please check your filter configuration and restart Logstash. {"exception"=>#<InterruptedRegexpError: Regexp Interrupted>, "backtrace"=>["org/jruby/RubyRegexp.java:1657:in `=~'", "org/jruby/RubyString.java:1729:in `=~'", "(eval):8618:in `initialize'", "org/jruby/RubyArray.java:1613:in `each'", "(eval):8616:in `initialize'", "org/jruby/RubyProc.java:281:in `call'", "(eval):2888:in `filter_func'", "c:/java8/elk5/logstash-5.0.0/logstash-core/lib/logstash/pipeline.rb:260:in `filter_batch'", "org/jruby/RubyProc.java:281:in `call'", "c:/java8/elk5/logstash-5.0.0/logstash-core/lib/logstash/util/wrapped_synchronous_queue.rb:186:in `each'", "org/jruby/RubyHash.java:1342:in `each'", "c:/java8/elk5/logstash-5.0.0/logstash-core/lib/logstash/util/wrapped_synchronous_queue.rb:185:in `each'", "c:/java8/elk5/logstash-5.0.0/logstash-core/lib/logstash/pipeline.rb:258:in `filter_batch'", "c:/java8/elk5/logstash-5.0.0/logstash-core/lib/logstash/pipeline.rb:246:in `worker_loop'", "c:/java8/elk5/logstash-5.0.0/logstash-core/lib/logstash/pipeline.rb:225:in `start_workers'"]}