Hi, I have hosted two different wiki application(wiki1 and wiki2) under same tomcat6. When i hit wiki1 from IE its works fine.But as soon as i hit wiki2, i start getting Permgen space exception. As per my understanding , probable reason for this is large number of class files gets loaded in classloader. Is that correct?(Any rough idea about number of classes deployed in xwiki will help in understanding the problem). Is there a way i can host two wiki app under same tomcat? Here are the details of my system:- OS:-window7 RAM:-4 GB java_opt- -Xms1536m -Xmx1536m //(mentioned as environment variable): tomcat version:-6.0.26 As per http://www.mkyong.com/tomcat/tomcat-javalangoutofmemoryerror-permgen-space/, tried to increas the permgensize by mentioning JAVA_OPTS and suggested value against it.But no help. Now, What else i can i do to resolve this perm gen issue?