Adjusted the bolded lines for optimum startup and performance:

# pwd
?/atlas/atlassian/confluence/bin
# cat setenv.sh
# Set the JVM arguments used to start Confluence.
# For a description of the vm options of jdk 8, see:
# http://www.oracle.com/technetwork/java/javase/tech/vmoptions-jsp-140102.html
# For a description of the vm options of jdk 11, see:
# https://docs.oracle.com/en/java/javase/11/tools/java.html
CATALINA_OPTS="-XX:+IgnoreUnrecognizedVMOptions ${CATALINA_OPTS}"
CATALINA_OPTS="-XX:-PrintGCDetails -XX:+PrintGCDateStamps -XX:-PrintTenuringDistribution ${CATALINA_OPTS}"
CATALINA_OPTS="-Xlog:gc+age=debug:file=$LOGBASEABS/logs/gc-`date +%F_%H-%M-%S`.log::filecount=5,filesize=2M ${CATALINA_OPTS}"
CATALINA_OPTS="-Xloggc:$LOGBASEABS/logs/gc-`date +%F_%H-%M-%S`.log -XX:+UseGCLogFileRotation -XX:NumberOfGCLogFiles=5 -XX:GCLogFileSize=2M ${CATALINA_OPTS}"
CATALINA_OPTS="-XX:G1ReservePercent=20 ${CATALINA_OPTS}"
CATALINA_OPTS="-Djava.awt.headless=true ${CATALINA_OPTS}"
CATALINA_OPTS="-Datlassian.plugins.enable.wait=300 ${CATALINA_OPTS}"
CATALINA_OPTS="-Xms1024m -Xmx6144m -XX:+UseG1GC ${CATALINA_OPTS}"
CATALINA_OPTS="-Dsynchrony.enable.xhr.fallback=true ${CATALINA_OPTS}"
CATALINA_OPTS="-Dorg.apache.tomcat.websocket.DEFAULT_BUFFER_SIZE=32768 ${CATALINA_OPTS}"
CATALINA_OPTS="-Djava.locale.providers=JRE,SPI,CLDR ${CATALINA_OPTS}"
CATALINA_OPTS="${START_CONFLUENCE_JAVA_OPTS} ${CATALINA_OPTS}"
CATALINA_OPTS="-Dconfluence.context.path=${CONFLUENCE_CONTEXT_PATH} ${CATALINA_OPTS}"
CATALINA_OPTS="-Djdk.tls.server.protocols=TLSv1.1,TLSv1.2 -Djdk.tls.client.protocols=TLSv1.1,TLSv1.2 ${CATALINA_OPTS}"
CATALINA_OPTS="-XX:ReservedCodeCacheSize=256m -XX:+UseCodeCacheFlushing ${CATALINA_OPTS}"

export CATALINA_OPTS

# ps -ef|grep -Ei confluence
conflue+ 22167     1 99 22:18 ?        00:00:35 /atlas/atlassian/confluence/jre//bin/java -Djava.util.logging.config.file=/atlas/atlassian/confluence/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=0027 -XX:ReservedCodeCacheSize=256m -XX:+UseCodeCacheFlushing -Djdk.tls.server.protocols=TLSv1.1,TLSv1.2 -Djdk.tls.client.protocols=TLSv1.1,TLSv1.2 -Dconfluence.context.path= -Datlassian.plugins.startup.options= -Djava.locale.providers=JRE,SPI,CLDR -Dorg.apache.tomcat.websocket.DEFAULT_BUFFER_SIZE=32768 -Dsynchrony.enable.xhr.fallback=true -Xms1024m -Xmx6144m -XX:+UseG1GC -Datlassian.plugins.enable.wait=300 -Djava.awt.headless=true -XX:G1ReservePercent=20 -Xloggc:/atlas/atlassian/confluence/logs/gc-2021-07-13_22-18-48.log -XX:+UseGCLogFileRotation -XX:NumberOfGCLogFiles=5 -XX:GCLogFileSize=2M -Xlog:gc+age=debug:file=/atlas/atlassian/confluence/logs/gc-2021-07-13_22-18-48.log::filecount=5,filesize=2M -XX:-PrintGCDetails -XX:+PrintGCDateStamps -XX:-PrintTenuringDistribution -XX:+IgnoreUnrecognizedVMOptions -Dignore.endorsed.dirs= -classpath /atlas/atlassian/confluence/bin/bootstrap.jar:/atlas/atlassian/confluence/bin/tomcat-juli.jar -Dcatalina.base=/atlas/atlassian/confluence -Dcatalina.home=/atlas/atlassian/confluence -Djava.io.tmpdir=/atlas/atlassian/confluence/temp org.apache.catalina.startup.Bootstrap start
root     22391 12708  0 22:19 pts/0    00:00:00 grep –color=auto -Ei confluence
# pwd
/atlas/atlassian/confluence/bin
# cat setenv.sh
 

HF!