Issue with Lucene generated deleted file that take up space until the app server is restarted

We have seen this in two cases where lucene is heavily used. The deleted files are coming clearly from lucene.

In one case running with -Dorg.apache.lucene.FSDirectory.class=org.apache.lucene.store.MMapDirectory
seem to fix the issue. In the second case (CURRIKI) it does not seem to fix the issue.

According to:
http://www.mail-archive.com/java-user@lucene.apache.org/msg29222.html
There is a case where this could happen depending on our application code:

---

if (indexReader!=null){
IndexReader newReader = indexReader.reopen();
if (newReader!=indexReader)

{ indexReader.close(); // close the old reader }

}

However, with Lucene 2.9, you can also use:

IndexReader r = writer.getReader();, which is a much simpler API. You still
need to close the reader when you are done with them however.

---

I'm not sure we are in this case but it seems we never close our readers but we also never reopen it..
We need to look into this