Hi Daniel,
I've been using the ARC PHP libraries to query my local Virtuoso
SPARQL end point. While this works fine for small amounts of data, the
memory usage of paging through hundreds of pages of results is too
much for my PHP process to handle.
Is there a better way to do SPARQL querying against a local Virtuoso
than using ARC?
Feel free to tell me to RTFM, but i'd appreciate any thoughts you
might have.
Thanks,
Dan
Dan,
What's the configuration of your machine? Basically, how much RAM is in
place?
BTW - Have you looked at the Virtuoso tunning guide?
Links:
1. http://docs.openlinksw.com/virtuoso/rdfperformancetuning.html
I think this is related to ARC or PHP or the SPARQL query he sends and
not the performance of the virtuoso data store.
Daniel: make sure that what handle the paging is the sparql query by
using LIMIT and OFFSET. Otherwise, a really big number of triples can be
returned, and then PHP can choke with its memory if too many objects are
created by ARC.
So, if you are performing the paging using SPARQL, a small amount of
data will be loaded in PHP objects (ARC) and will then be usable.
Does this answer your question?
Thanks,
Take care,
Fred
