There are several distributed triple stores (triple stores are a specialised graph store). http://4store.org http://4store.org http://virtuoso.openlinksw.com/

There are several distributed triple stores (triple stores are a specialised graph store). http://4store.org http://4store.org http://virtuoso.openlinksw.com/ http://virtuoso.openlinksw.com/ http://www.systap.com/bigdata.htm http://www.systap.com/bigdata.htm There's a paper on 4store here: http://4store.org/publications/harris-ssws09.pdf http://4store.org/publications/harris-ssws09.pdf