Hi. I’m having problems deleting a moderately large graph from a
jena-fuseki-1.0.1 database.
The graph contains approximately 60 million triples, and the database contains
about 70 million triples in total.
I’ve started Fuseki with 16G Heap. (JVM_ARGS=${JVM_ARGS:—Xmx16000M}). The
server has 32G RAM.
When I issue the DELETE command over http, I see this in the fuseki log:
16:12:03 INFO [24] DELETE
http://127.0.0.1:3030/stagingdb/data?graph=http://example.com/graph
<http://127.0.0.1:3030/stagingdb/data?graph=http://example.com/graph>
17:10:40 WARN [24] RC = 500 : Java heap space
17:10:40 INFO [24] 500 Java heap space (3,517.614 s)
i.e. it takes about an hour, and then 500s with an error about heap space.
I’ve also tried DROP and CLEAR SPARQL update statements but they timeout with
our default endpoint timeout of 30s.
I’ve also tried deleting 1000 triples at a time, from the graph by issuing a
sparql update statement like this:
DELETE {
GRAPH <http://example.com/graph <http://example.com/graph>>
{ ?s ?p ?o }
}
WHERE {
GRAPH <http://example.com/graph <http://example.com/graph>>
{ ?s ?p ?o }
}
LIMIT 1000
… but this times out too (which surprised me, as I only asked it to find and
DELETE 1000 triples).
What is the recommended way to delete this graph - I need to replace its
contents fairly urgently on a production system. We loaded it by loading 10,000
triples at a time, which worked fine, but I’m having trouble deleting its
current contents first.
Any pointers appreciated.
Thanks, Ric.
