More a test problem than anything, but also a general clean up issue.
deadlock if commit+newSearcher occurs during core close, can happen as a result of snappuller (occured in TestReplicationHandler)
[commit] Mark Robert Miller
SOLR-4060: ReplicationHandler can try and do a snappull and open a new IndexWriter after shutdown has already occurred, leaving an IndexWriter that is not closed.
[branch_4x commit] Mark Robert Miller