Loading quads too slow

[Daniel Hernandez]

Hi,

I'm loading a dataset in an nquads file that contains 170 millions of different
named graphs. However, the loading speed is getting lower during the loading:

$ 4s-import data -v -f nquads dataset.nq
removing old data
Reading <file:///home/daniel/dataset.nq>
Pass 1, processed 5000000 triples (5000000)
Pass 2, processed 5000000 triples, 315 triples/s
Pass 1, processed 5000000 triples (10000000)
Pass 2, processed 5000000 triples, 128 triples/s
Pass 1, processed 5000000 triples (15000000)
Pass 2, processed 5000000 triples, 51 triples/s
Pass 1, processed 5000000 triples (20000000)
Pass 2, processed 5000000 triples, 24 triples/s
Pass 1, processed 5000000 triples (25000000)
Pass 2, processed 1970000 triples

I notice that this does not occurs when loading a file with few named graphs.
Why? Is there a faster way to load the data?

Cheers!
Daniel

[swh]

That's really odd - have you checked /var/log/messages to see if there's any errors?

Have you tried loading a ntriples or turtle file to compare the speed?

Can't think of anything that would make it that slow.