[Myexperiment-discuss] Re: rdf.MyExperiment server performance problems?

[David R Newman]

Hi Edgar/Scott,

Sorry I didn't get back to you sooner. Are you still experiencing these 
problems?  The SPARQL endpoint has a JENA backend and sometimes the garbage 
collection isn't very good if a lot of complex queries have been run in a 
short space of time.  However this is monitored and the connection to the 
triplestore is restarted within an hour if this occurs.

Doing a quick test on some trivial queries seems to be alright.  Could you 
send me some examples of the query you have been trying to run and I will 
see if I can figure out what the problem is.

Regards

David Newman

--On Monday, October 05, 2009 22:26:00 +0200 "M. Scott Marshall" 
<address@hidden> wrote:

> Hi David,
>
> Are there known performance issues with the rdf.MyExperiment server
> SPARQL endpoint? Edgar seems to be experiencing timeouts and slow
> behavior.
>
> Scott wrote:
> > > > Any progress on the consumption of REST services or search across
> > > > repositories?
> Edgar wrote:
> > > As to the multiple repo's, I'm still squeezing things into ExtJS...
> > > I've  made a start with two REST services (which are both REST
> > > endpoints of  virtuoso) and I can do simple queries now. However, it's
> > > verrrry slow  and I don't know whether that's the REST stuff, or the
> > > actual server I'm  querying. One other thing I noticed is that the
> > > rdf.MyExperiment server  is painstakingly slow. Even using a browser
> > > and trivial query, the  response times out. Have you heard this before
> > > or could it be just me?
> Scott wrote:
> > Egads! No idea. It could very well be untuned servers with not enough of
> > anything but I don't know. But I suspect it's the actual server +
> > config. I'll sniff around for you if I get a chance. Can you supply me
> > with more detail about the virtuoso services? What version of Virtuoso?
> > On what ~hardware? As far as myExperiment, I will paste this into a
> > message to David Newman and Jits (aka Jiten Bhagat).
>
> Cheers,
> Scott
>
> --
> M. Scott Marshall
> Leiden University Medical Center / University of Amsterdam
> http://staff.science.uva.nl/~marshall