Second java process running on Liferay server

Issue

• On our production Liferay server we just saw a second java process running with these arguments:

java -cp /u01/liferay/tomcat-9.0.54/lib/annotations-api.jar:/u01/liferay/tomcat-9.0.54/lib/catalina-ant.jar:/u01/liferay/tomcat-9.0.54/lib/catalina-ha.jar:/u01/liferay/tomcat-9.0.54/lib/catalina-ssi.jar:/u01/liferay/tomcat-9.0.54/lib/catalina-storeconfig.jar:/u01/liferay/tomcat-9.0.54/lib/catalina-tribes.jar:/u01/liferay/tomcat-9.0.54/lib/catalina.jar:/u01/liferay/tomcat-9.0.54/lib/ecj-4.20.jar:/u01/liferay/tomcat-9.0.54/lib/el-api.jar:/u01/liferay/tomcat-9.0.54/lib/jasper-el.jar:/u01/liferay/tomcat-9.0.54/lib/jasper.jar:/u01/liferay/tomcat-9.0.54/lib/jaspic-api.jar:/u01/liferay/tomcat-9.0.54/lib/jsp-api.jar:/u01/liferay/tomcat-9.0.54/lib/ojdbc6.jar:/u01/liferay/tomcat-9.0.54/lib/servlet-api.jar:/u01/liferay/tomcat-9.0.54/lib/tomcat-api.jar:/u01/liferay/tomcat-9.0.54/lib/tomcat-coyote.jar:/u01/liferay/tomcat-9.0.54/lib/tomcat-dbcp.jar:/u01/liferay/tomcat-9.0.54/lib/tomcat-i18n-cs.jar:/u01/liferay/tomcat-9.0.54/lib/tomcat-i18n-de.jar:/u01/liferay/tomcat-9.0.54/lib/tomcat-i18n-es.jar:/u01/liferay/tomcat-9.0.54/lib/tomcat-i18n-fr.jar:/u01/liferay/tomcat-9.0.54/lib/tomcat-i18n-ja.jar:/u01/liferay/tomcat-9.0.54/lib/tomcat-i18n-ko.jar:/u01/liferay/tomcat-9.0.54/lib/tomcat-i18n-pt-BR.jar:/u01/liferay/tomcat-9.0.54/lib/tomcat-i18n-ru.jar:/u01/liferay/tomcat-9.0.54/lib/tomcat-i18n-zh-CN.jar:/u01/liferay/tomcat-9.0.54/lib/tomcat-jdbc.jar:/u01/liferay/tomcat-9.0.54/lib/tomcat-jni.jar:/u01/liferay/tomcat-9.0.54/lib/tomcat-util-scan.jar:/u01/liferay/tomcat-9.0.54/lib/tomcat-util.jar:/u01/liferay/tomcat-9.0.54/lib/tomcat-websocket.jar:/u01/liferay/tomcat-9.0.54/lib/websocket-api.jar:/u01/liferay/tomcat-9.0.54/lib/ext/activation.jar:/u01/liferay/tomcat-9.0.54/lib/ext/ccpp.jar:/u01/liferay/tomcat-9.0.54/lib/ext/com.liferay.petra.concurrent.jar:/u01/liferay/tomcat-9.0.54/lib/ext/com.liferay.petra.executor.jar:/u01/liferay/tomcat-9.0.54/lib/ext/com.liferay.petra.function.jar:/u01/liferay/tomcat-9.0.54/lib/ext/com.liferay.petra.io.jar:/u01/liferay/tomcat-9.0.54/lib/ext/com.liferay.petra.lang.jar:/u01/liferay/tomcat-9.0.54/lib/ext/com.liferay.petra.memory.jar:/u01/liferay/tomcat-9.0.54/lib/ext/com.liferay.petra.nio.jar:/u01/liferay/tomcat-9.0.54/lib/ext/com.liferay.petra.process.jar:/u01/liferay/tomcat-9.0.54/lib/ext/com.liferay.petra.reflect.jar:/u01/liferay/tomcat-9.0.54/lib/ext/com.liferay.petra.string.jar:/u01/liferay/tomcat-9.0.54/lib/ext/com.liferay.petra.url.pattern.mapper.jar:/u01/liferay/tomcat-9.0.54/lib/ext/com.liferay.registry.api.jar:/u01/liferay/tomcat-9.0.54/lib/ext/hsql.jar:/u01/liferay/tomcat-9.0.54/lib/ext/jms.jar:/u01/liferay/tomcat-9.0.54/lib/ext/jta.jar:/u01/liferay/tomcat-9.0.54/lib/ext/jutf7.jar:/u01/liferay/tomcat-9.0.54/lib/ext/mail.jar:/u01/liferay/tomcat-9.0.54/lib/ext/mariadb.jar:/u01/liferay/tomcat-9.0.54/lib/ext/persistence.jar:/u01/liferay/tomcat-9.0.54/lib/ext/portal-kernel.jar:/u01/liferay/tomcat-9.0.54/lib/ext/portlet.jar:/u01/liferay/tomcat-9.0.54/lib/ext/postgresql.jar:/u01/liferay/tomcat-9.0.54/lib/ext/support-tomcat.jar -Dconfiguration.impl.quiet=true -Djava.awt.headless=true -Dserver.detector.quiet=true -Dsystem.properties.quiet=true com.liferay.petra.process.local.LocalProcessLauncher

• Our "normal" java process was also running, like this:

/usr/bin/java -Djava.util.logging.config.file=/u01/liferay/tomcat-9.0.54/conf/logging.properties -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager -Djdk.tls.ephemeralDHKeySize=2048 -Djava.protocol.handler.pkgs=org.apache.catalina.webresources -Dorg.apache.catalina.security.SecurityListener.UMASK=0022 -server -d64 -Djgroups.bind_addr=gsssv-prd-ptl02.rspcanet.com -Djgroups.bind_port=7800 -Djgroups.tcpping.initial_hosts=gsssv-prd-ptl02.rspcanet.com[7800],ixssv-prd-ptl02.rspcanet.com[7800] -Dfile.encoding=UTF-8 -Djava.locale.providers=JRE,COMPAT,CLDR -Djava.net.preferIPv4Stack=true -Duser.timezone=GMT -Xms8G -Xmx8G -XX:MaxNewSize=4G -XX:NewSize=4G -XX:SurvivorRatio=7 -XX:+UseStringDeduplication -XX:+UseG1GC -XX:+BindGCTaskThreadsToCPUs -XX:+UseFastAccessorMethods -XX:+UseLargePages -javaagent:/u01/software/newrelic/newrelic.jar -Dignore.endorsed.dirs= -classpath /u01/liferay/tomcat-9.0.54/bin/bootstrap.jar:/u01/liferay/tomcat-9.0.54/bin/tomcat-juli.jar -Dcatalina.base=/u01/liferay/tomcat-9.0.54 -Dcatalina.home=/u01/liferay/tomcat-9.0.54 -Djava.io.tmpdir=/u01/liferay/tomcat-9.0.54/temp org.apache.catalina.startup.Bootstrap start

Environment

• Liferay DXP 7.2

Resolution

• Liferay, by default, generates forked processes for Documents and Media preview generation according to the following property:

#
    # Set this to true if you want preview generation to use a separate Java
    # process. This will utilize extra resources from the operating system while
    # improving the portal's stability.
    #
    # Env: LIFERAY_DL_PERIOD_FILE_PERIOD_ENTRY_PERIOD_PREVIEW_PERIOD_FORK_PERIOD_PROCESS_PERIOD_ENABLED
    #
    dl.file.entry.preview.fork.process.enabled=true

• The property dl.file.entry.preview.fork.process.enabled is set to true by default. This property was established for Documents and Media preview generation and this creates a separate Java process. 
• The reason for this property being set to true by default is to utilize extra resources from the operating system while improving the portal's stability.

Additional Information

• Liferay DXP 7.2. Portal Properties