Traceback (most recent call last):
  File "/usr/sbin/update-apt-xapian-index", line 684, in <module>
    res = updateIndex(dbpath, addons, progress)
  File "/usr/sbin/update-apt-xapian-index", line 369, in updateIndex
    db.flush()
DatabaseCorruptError: Db block overwritten - are there multiple writers?