I am running Jenkins 1.646 from source using mvn jenkins-dev:run. It seems to be logging at the DEBUG level making page load very slow. How do I change the log level of Jenkins. I have tried the usual util.logging properties file, but I can't get it working.

01:58:52.542 Handling POST /ajaxBuildQueue from 0:0:0:0:0:0:0:1 : RequestHandlerThread[#5] DEBUG o.apache.commons.jelly.JellyContext - Registering tag library to: jelly:swt taglib: org.apache.commons.jelly.tags.swt.SwtTagLibrary 01:58:52.542 Handling POST /ajaxBuildQueue from 0:0:0:0:0:0:0:1 : RequestHandlerThread[#5] DEBUG o.apache.commons.jelly.JellyContext - Registering tag library to: jelly:swt taglib: org.apache.commons.jelly.tags.swt.SwtTagLibrary

I followed the various ideas from http://stackoverflow.com/questions/35218415/how-to-set-jenkins-log-level-from-maven . But those did not help.