This is an old revision of the document!
To filter out Library updates from debug log simple find the below code:
<category name="org.serviio">
<priority value="DEBUG"/>
</category>
and add the below code under it:
<category name="org.serviio.library.local">
<priority value="INFO"/>
</category>
<category name="org.serviio.library.online">
<priority value="INFO"/>
</category>