NoMethodError: undefined method `<=' for nil:NilClass
map_cleanup at /export/elk/apps/logstash/vendor/bundle/jruby/1.9/gems/logstash-codec-multiline-2.0.7/lib/logstash/codecs/identity_map_codec.rb:211
delete_if at org/jruby/RubyHash.java:1642
map_cleanup at /export/elk/apps/logstash/vendor/bundle/jruby/1.9/gems/logstash-codec-multiline-2.0.7/lib/logstash/codecs/identity_map_codec.rb:210
start at /export/elk/apps/logstash/vendor/bundle/jruby/1.9/gems/logstash-codec-multiline-2.0.7/lib/logstash/codecs/identity_map_codec.rb:53
loop at org/jruby/RubyKernel.java:1479
start at /export/elk/apps/logstash/vendor/bundle/jruby/1.9/gems/logstash-codec-multiline-2.0.7/lib/logstash/codecs/identity_map_codec.rb:50