elasticsearch/elasticsearch — pull request #6794 by bleskes (2014-07-09 07:06:11+00:00)
Title: [Engine] checkVersionMapRefresh must be called under a read lock

The operation looks at indexWriter.getConfig(), which can throw a `org.apache.lucene.store.AlreadyClosedException` if the engine is already closed.

Relates to #6443, #6786