Service startup is too long with default tomcat8 settings

Hi there, I installed xwiki 10.0 and the startup time was very very long.
Tomcat8 service stalls for some seconds (around 10 to 15) but it took 10 minutes for xwiki to show me the login screen (my configuration shows nothing but the login screen as default page).

I'm using a VPS from scaleway : X86, 2 vCPU's, 2 gigs of ram and SSD as storage (not sure what they are using exactly, some infos here : https://www.scaleway.com/faq/servers/volumes/ ). The server is not the most powerfull but it runs well (dedicated to xwiki, no other app installed).

Anyway, after the long startup, everything ran smoothly. After digging the /var/log/tomcat8/catalina.out , I noticed entries like
23-Feb-2018 13:33:22.864 INFO [main] org.apache.catalina.startup.Catalina.start Server startup in 525593 ms

Hint was this line : org.apache.jasper.servlet.TldScanner.scanResourcePaths No TLD files were found in resource path [/WEB-INF/].
Fix (or workaround, I ain't tomcat expert...) was to add

"org.apache.jasper.servlet.TldScanner.level = FINE"
in
/etc/tomcat8/logging.properties

result :
02-Mar-2018 23:18:08.825 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDescriptor Deployment of configuration descriptor /etc/tomcat8/Catalina/localhost/xwiki.xml has finished in 54,574 ms

From what I understand, I should disable jar/war scanning from my tomcat config, but could not find the appropriate setting in the appropriate file.