What is virtuoso-t doing and why?

[Marko Vojinovic]

I am seeing the following problem appearing on random occasions during regular 
usage of my regular updated KDE/F14/64bit system.

The desktop becomes extremely slow and unresponsive, out of the blue. It lasts 
for about a minute or two, and then reverts to normal. If i happen to have a 
terminal open when it happens, I can see in top that usage of both CPUs goes 
to 100%. However, it's not because some process is using them, but because 
both CPUs are wasting cycles in "wait" state for I/O.

Then if I manage to start iotop to see what is sucking all disk I/O, I see 
that  99.99% of I/O is being used by something like

   virtuoso-t +foreground +configfile /tmp/virtuoso_Lh1825.ini +wait

Would someone explain what is this, why is it running on random, what triggers 
it, and --- most importantly --- why is it configured by default to suck all 
life out of my system during its (presumably normal) operation?

yum info virtuoso-opensource says:

Summary     : A high-performance object-relational SQL database
Description : Virtuoso is a scalable cross-platform server that combines 
SQL/RDF/XML Data Management with Web Application Server and Web Services 
Platform functionality.

This suggests that it is some kind of database used by KDE (or something 
else?), so I can understand that it can be resource-hungry. However, I don't 
understand what is its purpose on my system?

If I try to yum remove it, it wants to remove most of the OS istallation, 
including kdebase, so I guess it is something very required by KDE.

I would be very thankful if someone explains what this is and how to make it 
do its work only when the system is idle enough (say, when the screensaver has 
been active for half an hour, or something like that), and not in the middle 
of my regular work.

TIA, :-)
Marko