%META:TOPICPARENT{name="VirtTipsAndTricksGuide"}%


---+How to configure Sponger to use Asynchronous Query (AQ) threads?


---++What?
Configuring the number of AQ threads used by the Sponger.

---++Why?

Cache invalidation is affected by the number of AQ threads allocated to the Sponger. It also affects the number of concurrent tasked handled by a Sponger instance. 

---++How?


There is a <code>AsyncQueue = 1/0</code> in the SPARQL section of the virtuoso ini file. This is obsolete. Infact the AQ only is used to protect cache from bad data 

Steps:

   1 [[http://virtuoso.openlinksw.com/dataspace/dav/wiki/Main/VirtTipsAndTricksGuideSPARQLEndpointProtection][Ensure your SPARQL Endpoint is protected]]
   1 Configure the Sponger uses AQ by enabling it via the Virtuoso instance INI file
<verbatim>
# virtuoso.ini
...
[SPARQL]
...
AsyncQueue = 1
...
</verbatim>


---++Related

   * [[VirtTipsAndTricksGuide][Virtuoso Tips and Tricks Collection]]
   * [[http://docs.openlinksw.com/virtuoso/rdfsparql.html][Virtuoso Documentation]]
   * [[VirtSponger][Virtuoso Sponger]]