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Why tomcat(64bit) can not access more than 4.5g of ram on windows server?

We have an java web application deployed on tomcat8 and on windows server 2012.server has 16g of ram and we set options for tomcat to use maximum 8g of ram. But tomcat can not access more than 4.5g of ram and cpu usage goes up to 100% and we have to restart tomcat. Why tomcat cant access more than 4.5g of ram?
We also set jvm options to java on control panel as answerd on previous questions.

Docker memory limits no taking effect for Java Apps in Centos 7 host

I am trying to deploy several Java (spring boot) apps in docker containers in 1 host, where I set memory limits (--memory=30m --memory-swap=50m) for each.
However when I check the limits using docker container stats, I see each container is using >400MB of the host's RAM. Due to this I cannot start all the containers I need as the kernel kills some of them (OOM).
What do I need to do to ensure that the containers' memory is controlled using the docker memory options?
My host is a digital ocean centos 7. Thanks

Main reason for this issue is that JRE is not aware it is running inside a container.
Let JVM detect how much memory is available in Docker container
https://blog.csanchez.org/2017/05/31/running-a-jvm-in-a-container-without-getting-killed
JAVA_OPTS="-server -Djava.net.preferIPv4Stack=true -XX:+UnlockExperimentalVMOptions -XX:+UseCGroupMemoryLimitForHeap -XX:MaxRAMFraction=1"
Make sure you have JDK 8-131 or above version
In case of JDK-9 it will be available to correctly detect available memory inside container.
Additional Referece: Docker run -m doesnt set the limit (JVM takes up the entire host machine's size for xms and xmx)
and
https://developers.redhat.com/blog/2017/03/14/java-inside-docker/

Want to profiling web application in JBoss Server in local machine

in my local machine I am running an web application in JBoss server. I am using JVisual VM for profiling my application. When I am trying to point/connect to JBoss with JVisual VM, My application is getting tremendously slow or its getting down(not working any more).
I want to do instrumentation profiling to get the actual memory usage for various objects.
OS: Windows 7 Enterprise
Processor: Core 2 Duo #3.00GHz 3.00GHz
RAM: 4.00 GB

Did you use the JBoss client JAR:
jvisualvm.exe -cp:a c:\wildfly-8.1.0.Final\bin\client\jboss-client.jar
You will need to modify the JVM security policy:
grant codebase "file:${java.home}/../lib/tools.jar" {
permission java.security.AllPermission;
};
jstatd -J-Djava.security.policy=security.policy
use the add-user.sh script to add a Management user.
Add a Remote Host in VisualVM and use a JMX Connection with the Management user created above.
Full details on how to setup Visual VM: http://www.mastertheboss.com/jboss-server/wildfly-8/monitoring-wildfly-using-visualvm

Monitor WebSphere Application Server console with JVisualVM

I am running several applications in IBM WebSphere Application Server (WAS) 7. The applications can be managed from the WAS console: http://{myserver}:9060/ibm/console/login.do
I am able to monitor those deployed applications with JVisualVM. How can I monitor the WAS console with JVisualVM. Does it have a default JMX port?

Monitor JVM on tomcat service

Hi I noticed that different tools for monitoring JVM require that the process will be java.exe in the taskbar. Its process id is supplied to them and then statistics regarding garbage collection and etc are returned. When running tomcat as a service, there is no a process named jave.exe but it is tomcat6.exe.
How can I get statistics regarding the JVM tomcat6 uses ?

Enable JMX in Tomcat and then connect via JConsole or JVisualVM. The name of the process is not relevant.