Hi Elli!
Thanks for sharing your experience. I was also thinking of setting up
multiple Fuseki instances to work around this problem.
I'm currently investigating Bigdata as an alternative to Fuseki+LARQ. It
seems to have a more mature text index (though not very well documented)
which is kept up to date with the triple data. I wrote up some
instructions for setting it up (mainly for myself), feel free to check
if you want to give it a try:
http://code.google.com/p/onki-light/wiki/InstallBigdata
-Osma
13.03.2013 15:27, Elli Schwarz kirjoitti:
Osma,
I noticed the same problem this past summer. We had to set up two
different Fuseki instances, each one with a different config file
running on a different port, in order to maintain two Fuseki datasources
with independent indexes. You should be able to do this also, but we
were using the "fuseki" startup script, and we had to modify it to make
sure that each instance was started by a different user to avoid the
"fuseki stop" or "fuseki status" command from referring to the wrong
instance or giving incorrect status information. (Hopefully one day this
startup approach will be improved - I've been watching JENA-201 to
create a deployable .war for Fuseki...)
By the way, +1 on fixing JENA-164 someday - I could REALLY use that
feature! As you can imagine, it is quite disruptive on our project that
after every data ingestion we need to take down Fuseki and rerun the
indexer. If we don't do it, our queries which rely on the index don't
work and we often forget why! Aren't there others out there who are
using LARQ with Fuseki based on your instructions who rely on an
up-to-date index?
-Elli
------------------------------------------------------------------------
*From:* Osma Suominen <[email protected]>
*To:* [email protected]
*Sent:* Wednesday, March 13, 2013 4:39 AM
*Subject:* LARQ multiple indexes not working?
Hi!
I'm running into problems trying to configure multiple LARQ indexes into
the same Fuseki instance. It appears that only one of the indexes is
actually used.
This is the simplest test case I could think of:
1. Install Fuseki with LARQ. I used my own instructions [1]. I used
yesterday's svn HEAD versions of both LARQ and Fuseki. I had to fix the
versions of ARQ and TDB used by LARQ and compile it myself.
2. Start Fuseki with the attached configuration that defines two
services (serviceA and serviceB), each with a dataset (datasetA and
datasetB) having different TDB and Lucene index locations.
3. Load test data:
A.nt <http://a.nt/> contains this:
<http://example.org/A> <http://www.w3.org/2000/01/rdf-schema#label>
"dataset A" .
B.nt <http://b.nt/> contains this:
<http://example.org/B> <http://www.w3.org/2000/01/rdf-schema#label>
"dataset B" .
I load these using s-put, like this:
./s-put http://localhost:3030/dsA/data default A.nt
./s-put http://localhost:3030/dsB/data default B.nt
4. Now make sure the Lucene indexes are updated (I wish JENA-164 was
fixed some day):
- shut down Fuseki
- rm -r /tmp/lucene*
- start up Fuseki again
5. Verify that the proper data is loaded by executing this query for
both dsA and dsB:
SELECT ?label
WHERE { ?s ?p ?label }
I get the expected result, i.e. "dataset A" for dsA and "datasetB" for dsB.
6. Try a query that uses the LARQ index for both dsA and dsB:
PREFIX pf: <http://jena.hpl.hp.com/ARQ/property#>
SELECT ?label
WHERE { ?label pf:textMatch 'dataset' }
Now I get the same result "dataset B" for both dsA and dsB. It appears
that both queries go to the same index!
The contents of /tmp/luceneA and /tmp/luceneB appear to be identical
w.r.t. file sizes so I believe the indexese were written into the proper
places, but the wrong index is used during query time. I haven't
double-checked this though.
-Osma
[1] http://code.google.com/p/onki-light/wiki/InstallFusekiLARQ
-- Osma Suominen | [email protected]
<mailto:[email protected]> | +358 40 5255 882
Aalto University, Department of Media Technology, Semantic Computing
Research Group
Room 2541, Otaniementie 17, Espoo, Finland; P.O. Box 15500, FI-00076
Aalto, Finland
--
Osma Suominen | [email protected] | +358 40 5255 882
Aalto University, Department of Media Technology, Semantic Computing
Research Group
Room 2541, Otaniementie 17, Espoo, Finland; P.O. Box 15500, FI-00076
Aalto, Finland
