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Tomcat8 setenv.sh
#
# Cutom Environment Variables for Tomcat
#
############################################
export JAVA_HOME=/usr/lib/jvm/java-7-oracle/jre
export PATH=${JAVA_HOME}/bin:${PATH}
############################################
#
# JAVA_OPTS
# You could do all this in one export command
# But I am going to be long winded and explain
# Why and add links
#
# Oracle Notes
# - https://docs.oracle.com/javase/8/docs/technotes/tools/windows/java.html
# - A good visual
# https://redstack.wordpress.com/2011/01/06/visualising-garbage-collection-in-the-jvm/
#############################################
# -server
# Select the java HotSpot Server JVM
# The 64-bit version of the JDK support only the Server VM,
# so in that case the option is implicit
# ... so it's redundant to today's world but it make me feel good.
export JAVA_OPTS="-server"
# -Xms/Xmx
# Xms Sets the initial size of the Heap
# Xmx sets the Maximum size of the Heap.
# http://stackoverflow.com/questions/16087153/what-happens-when-we-set-xmx-and-xms-equal-size
# http://crunchify.com/jvm-tuning-heapsize-stacksize-garbage-collection-fundamental/
export JAVA_OPTS="$JAVA_OPTS -Xms1024M -Xmx1024M"
# -NewSize/MaxNewSize
# Set the size of the young generation
# Most newly created objects are made here
# Objects taht did not become unreachbale and survice the young
# Generation heap are copied to the Old Generation
# See http://www.cubrid.org/blog/dev-platform/understanding-java-garbage-collection
# https://redstack.wordpress.com/2011/01/06/visualising-garbage-collection-in-the-jvm/
export JAVA_OPTS="$JAVA_OPTS -XX:NewSize=512m -XX:MaxNewSize=512m"
# -PermSize/MaxPermSize
# Store classes and interned character strings
# http://stackoverflow.com/questions/12114174/what-does-xxmaxpermsize-do
# Warning!
# Decprecated in Java 8!! replace -XX:MetaspaceSize !!!
export JAVA_OPTS="$JAVA_OPTS -XX:PermSize=256m -XX:MaxPermSize=256m"
# -UseConcMarkSweepGC
# Also called the low latency GC since pausing time is very short
# When this is enabled it also enabled
# -XX:+UseParNewGC Potentially speed up your generation GC
# by a factor equal to the number of CPUS
# (see http://stackoverflow.com/questions/2101518/difference-between-xxuseparallelgc-and-xxuseparnewgc)
# http://www.cubrid.org/blog/dev-platform/understanding-java-garbage-collection/
export JAVA_OPTS="$JAVA_OPTS -XX:+UseConcMarkSweepGC"
# -XX:+CMSIncrementalMode
#
# I am not going to set this one but it's worthe mentioning
# It has been deprecated in Java 8. It is useful when you have 1 or 2
# CPU machine. It helps reduce latency by doing smaller garbage collections
# see thies sites for details
# http://www.fixdeveloper.com/2014/03/jvm-tuning-cmsincrementalmode-overrides.html
# http://www.oracle.com/technetwork/java/javase/gc-tuning-6-140523.html#icms
# -CMSClassUnloadingEnabled
# In an old school java program classes are forever. But with
# Modern languages like Groovy... Classes are created at runtime, every
# scirpt may create a few new classes. With this set the PermGen space will
# Be garbage collecte3d. Without this you have a memory Leak.
#
# Must also have UseConcMarkSweepGC set for this to work.
#
# http://stackoverflow.com/questions/3334911/what-does-jvm-flag-cmsclassunloadingenabled-actually-do
export JAVA_OPTS="$JAVA_OPTS -XX:+CMSClassUnloadingEnabled"
# -DisableExlicitGC
# Explicit calls to System.gc() are completely ignored
#
# http://stackoverflow.com/questions/12847151/setting-xxdisableexplicitgc-in-production-what-could-go-wrong
export JAVA_OPTS="$JAVA_OPTS -XX:+DisableExplicitGC"
# -HeapDumpPath
# Set the file where the heap dump will write out its error
export JAVA_OPTS="$JAVA_OPTS -XX:HeapDumpPath=/10x13/logs/tomcat8/java_heapdump_pid_%p.log"
# -java.awt.headless
# Basically tell the JVM not to load awt libraries
# Your server is not a desktop app, there is more to this rule than that.
# If you want to go into it check out.
# https://blog.idrsolutions.com/2013/08/what-is-headless-mode-in-java/
# http://www.oracle.com/technetwork/articles/javase/headless-136834.html
export JAVA_OPTS="$JAVA_OPTS -Djava.awt.headless=true"
# -java.security.egd
# This one is abit of a debate
# If you don't set this it will use /dev/random on startup
# which can block and make tomcat startup slower.
# But it's technically more secure... but no one has shown
# a way to break the results of urandom which is faster.
# For more details see.
# http://www.2uo.de/myths-about-urandom/
export JAVA_OPTS="$JAVA_OPTS -Djava.security.egd=file:/dev/./urandom"
#################################################
# CATALINA_OPTS
# This are basically JAVA_OPTS but only used by tomcat
# and only run on Tomcat start see
# http://stackoverflow.com/questions/11222365/catalina-opts-vs-java-opts-what-is-the-difference
# for more details
#
################################################
# -jmcremot..
# Turn onthe jmxremote so you can use JConsole or VisualVM
# to monito the jvm remotely
# See
# https://tomcat.apache.org/tomcat-7.0-doc/monitoring.html
# http://www.mkyong.com/tomcat/jconsole-jmx-remote-access-on-tomcat/
# http://www.javaworld.com/article/2072322/from-jconsole-to-visualvm.html
export CATALINA_OPTS="$CATALINA_OPTS -Dcom.sun.management.jmxremote"
export CATALINA_OPTS="$CATALINA_OPTS -Dcom.sun.management.jmxremote.port=9090"
export CATALINA_OPTS="$CATALINA_OPTS -Dcom.sun.management.jmxremote.authenticate=false"
export CATALINA_OPTS="$CATALINA_OPTS -Dcom.sun.management.jmxremote.ssl=false"
#This gets the local IP address
IP_ADDR=`ip route get 8.8.8.8 | awk '{print $NF; exit}'`
export CATALINA_OPTS="$CATALINA_OPTS -Djava.rmi.server.hostname=$IP_ADDR"
export CATALINA_HOME=/10x13/apps/tomcat8
export CATALINA_OUT=/10x13/logs/tomcat8/catalina.out
export CATALINA_PID=/var/run/tomcat8/tomcat.pid
@mahamuniraviraj

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mahamuniraviraj commented Jun 26, 2017

thanks pal. I found it very useful.

@webshopboys

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webshopboys commented Sep 11, 2017

Big thankyou!

@kouzouigh

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kouzouigh commented Feb 1, 2018

Thanks for sharing !

@imtiaz-m4

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imtiaz-m4 commented Jul 5, 2018

What does this "/10x13/" means in the paths? Can you please elaborate. Thanks

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