If the Linux "at" package is not installed or the spectrum user is not authorized to run "at" command when you modify the Web Server Memory (Maximum Memory the Server Can Use) and click on "Save and Reconfigure" you will get an error that you cannot restart the OneClick tomcat. Now, the new value is properly saved in the tomcat-server-config file under $SPECROOT/custom/common/config but even if you manually restart the Tomcat from $SPECROOT/tomcat /bin the modification will not be operative and tomcat will start with the "old" -Xmx value.
Release : 20.2
Component : Spectrum Applications
Install the "at" package or if you have implemented the /etc/at.deny specify the Spectrum user in the /etc/at.allow
Work-around: manually modify the tomcat catalina.sh file