Again, for those who are using the unpatched db4 redland backend, if you get issues where libferris apps just eat CPU and seem to hang, if your backtrace includes Ferris::RDF::RedlandIterator::__advance() calling librdf_iterator_next() then there is a fair chance your RDF db4 files are screwed. You can try to recover them with the below.... sorry about the long standing issue folks.
#!/bin/bash
cd ~/.ferris/rdfdb
for if in myrdf-po2s.db myrdf-so2p.db myrdf-sp2o.db
do
echo "Fixing: $if"
db_dump -r $if >| dump
rm -f $if
db_load -f dump $if
rm -f dump
done
