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How can we manage our memory more effectively with RunDeck 3.4.1 and TomCat 9 on Windows Server 2016 to prevent locking and crashing?

We have a Windows Server 2016 vm with 8192 MB ram with six cores and running RunDeck 3.4.1 with TomCat 9 from the rundeck.war file. Lately we've been seeing a couple issues crop up. First, RunDeck keeps user login sessions open well past the 30 minute idle limit in TomCat and Second, RunDeck does not respond or is extremely sluggish when the StandBy Memory leaves less than 400 MB of 'free memory' as if it never gets access to the StandBy Cache or queue or the priority is so low it can't get access to it. When a job fails, this problem gets even worse; but it also happens on successful jobs. This is causing our server to become unresponsive multiple times a day and the only way so far to free it is to manually release sessions in TomCat and/or to reboot the server completely. In the RunDeck Profile I have set the JVM to export RDECK_JVM="$RDECK_JVM -Xmx2048m -Xms512m -XX:MaxMetaspaceSize=512m -server".

Following the official documentation, those parameters (Xmx, Xms, and MaxMetaspaceSize) need to be defined in the setenv.bat file, take a look.

Tomcat 8 - POST and PUT requests slow when deployed on RHEL

I have developed a REST API using Spring Framework. When I deploy this in Tomcat 8 on RHEL, the response times for POST and PUT requests are very high when compared to deployment on my local machine (Windows 8.1). On RHEL server it takes 7-9 seconds whereas on local machine it is less than 200 milliseconds.
RAM and CPU of RHEL server are 4 times that of local machine. Default tomcat configurations are used in both Windows and RHEL. Network latency is ruled out because GET requests take more or less same time as local machine whereas time taken to first byte is more for POST and PUT requests.
I even tried profiling the remote JVM using Visual JVM. There are no major hotspots in my custom code.
I was able to reproduce this same issue in other RHEL servers. Is there any tomcat setting which could help in fixing this performance issue ?

The profiling log you have placed means nothing, more or less. It shows the following:
The blocking queue is blocking. Which is normal, because this is its purpose - to block. This mean there is nothing to take from it.
It is waiting for connection on the socket. Which is also normal.
You do not specify what is your RHEL 8 physical/hardware setup. The operating system here might not be the only thing. You can not eliminate still network latency. What about if you have SAN, the SAN may have latency itself. If you are using SSD drive and the RHEL is using SAN with replication you may experience network latecy there.
I am more inclined to first check the IO on the disk than to focus on operating system. If the server is shared there might be other processes occupying the disk.
You are saying that the latency is ruled out because the GET requests are taking the same time. This is not enough to overrule it as I said this is the latency between the client and the application server, it does not check the latency between your app server machin and your SAN or disk or whatever storage is there.

Jboss startup very slow on Windows Server

I'm using Jboss(WildFly 9) to host my Solr application on a Windows Server(2012), but if I start JBoss it's very slow and taking at least 15 mins to start. There is only one app (solr.war).
The same JBoss in my local with the same WAR takes less than a minute to start.
The JVM is set as MIN 4GB and Max 16GB on the servers.
What could be the reason it is very slow?

Try starting the sever without war and if it takes normal time in bootup then check the war code else check the jboss version and logs.

Improving JBoss 5 slow startup

We upgraded from JBoss 4 (and JDK 5) to JBoss 5 (and JDK 6). The problem is that the start time has gone from 1.5 minutes (on JBoss 4) to more than 4 minutes.
18:53:35,444 INFO [ServerImpl] JBoss (Microcontainer) [5.1.0.GA (build: SVNTag=JBoss_5_1_0_GA date=200905221053)] Started in 3m:9s:262ms
It seems like the component that is taking JBoss the longest time to initialize is the JMX
18:50:41,926 INFO [LogNotificationListener] Adding notification listener for logging mbean "jboss.system:service=Logging,type=Log4jService" to server org.jboss.mx.server.MBeanServerImpl#1adc122[ defaultDomain='jboss' ]
18:52:38,797 INFO [JMXConnectorServerService] JMX Connector server: service:jmx:rmi://lharel2/jndi/rmi://lharel2:1090/jmxconnector
From the DEBUG server log, I get these lines at the problematic time:
2009-12-18 18:51:00,886 DEBUG [org.jboss.deployment.MappedReferenceMetaDataResolverDeployer] (main) vfsfile:/C:/QC/Views/QCDev/jboss-5.1.0.GA/server/default/deploy/jmx-console.war/ endpoint mappings:
2009-12-18 18:51:00,886 DEBUG [org.jboss.deployment.MappedReferenceMetaDataResolverDeployer] (main) Processing unit=jmx-console.war, structure: jmx-console.war
2009-12-18 18:52:35,209 DEBUG [org.jboss.deployment.OptAnnotationMetaDataDeployer] (main) Deployment is metadata-complete, skipping annotation processing, ejbJarMetaData=null, jbossWebMetaData=org.jboss.metadata.web.spec.Web23MetaData#1f, jbossClientMetaData=null, metaDataCompleteIsDefault=false
There is no EJB in the project.
The memory settings are:
-Xms128m -Xmx512m -XX:MaxPermSize=256m
Do you have any idea how JBoss start time can be improved?
Update: so far no luck, I tried shreeni's suggestion (changed the scanning xmls). The server is not running in debug mode so MicSim's suggestion is not relevant

A shot into the blue sky without more information
Network timeouts: 1,5 minutes of delay when deploying jmx-console.war may indicate a network timeout (e.g. 3 x 30 seconds). Try to start JBoss and bind it to a specific IP address using the -b command line argument or the jboss.bind.address system property. Also, try to make sure your host and DNS resolution settings on your system are correct.
JMX is also using RMI and you may want to set the RMI server host name as system property. On some Linux distributions, RMI has problems with looking up the correct hostname and jmx-console.war may try to connect to the 'wrong localhost'. The system property is java.rmi.server.hostname
System tracing: If that does not help, you may want to use strace to start the java process, so you can see the point where the system hangs (if it really does hang due to a network timeout or similar).

That is an awfully big gap in the logs. I suggest changing the log configuration to log everything at DEBUG level, rather than INFO. This will generate an awful lot more log entries, but hopefully will help you narrow it down.
The easiest way to do this is to set the -Djboss.server.log.threshold=DEBUG system property when you start JBoss

I had an issue like this but I found a good improvement by setting the initial and max heap size to same values, I mean:
-Xms512m -Xmx512m
With this, I improved from 4 to 2 minutes the starting time.

Your suspicion about the jmx-console can be misleading. There may be other components doing work in the background unrelated to the jmx-console. In my experience, we had an issue where a small war file appeared to take 3 minutes to load! It was innocent. The culprit was partly due to an EAR file with many wars and jars.
While I'm no expert, I would suggest the following:
Try turning up the logging to TRACE. By doing this, I witnessed one of the deployers (EJBDeployer, I think) unnecessarily scanning WARs in one of our EARs. I then manually disabled the scanning of those WAR files.
Run wireshark during the startup. I discovered some war files were hanging while waiting for a response from an external DTD request. Those websites were either now non-existent or would not properly serve the DTD files to java-based programs. I could speed it up by either having the programmers use local DTD files or mirroring those DTDs locally and having /etc/host loopback locally.

You could refer to this link to avoid unnecessary annotation scanning which could speedup your server start

See http://community.jboss.org/wiki/jboss5xtuningslimming especially the "Tuning" part.

I'm using JBoss 5.1.0 with a Macbook pro (2.26ghz 4gb) without applications it start in 54s
15:00:26,449 INFO [ServerImpl] JBoss (Microcontainer) [5.1.0.GA (build: SVNTag=JBoss_5_1_0_GA date=200905221634)] Started in 54s:720ms
I made a new configuration based on the "default". The JMS dataosurce points to a Postgres database instead of the "Hypersonic Database" (in memory database)

I suppose you are starting in debug mode. This mode can be up to 3 times slower than normal mode.
But there might be also a problem when switching from JDK5 to JDK6. I found this solution here on the net:
I've solved that. It's a debugging issue. I've changed my debug settings from:
wrapper.java.additional.26=-Xdebug
wrapper.java.additional.27=-Xnoagent
wrapper.java.additional.28=-Djava.compiler=NONE
wrapper.java.additional.27=-Xrunjdwp:transport=dt_socket,address=7199,server=y,suspend=n
to:
wrapper.java.additional.26=-Xdebug
wrapper.java.additional.27=-Xrunjdwp:transport=dt_socket,address=7199,server=y,suspend=n
and JBoss becomes fast again.
Hope this helps.

Do you need the JMX console application? Pragmatic thing would be to un-deploy it from the server, you could still use the jconsole or jvisualvm for basically the same thing.

Turn off annotation scanning and other features you don't need https://community.jboss.org/wiki/jboss5xtuningslimming
When you start/stop JBoss from eclipse, it does not clean up the tmp & work folders correctly. Setup an External Tool configuration and run a batch file to delete everything in tmp & work folders before each startup.
I was able to speedup running the "default" profile from 15/20 minutes to 5 minutes.

Tomcat shuts down automatically

I'm using Apache and Tomcat on a Windows server and since this morning, Tomcat stops working without any logs. It doesn't hang, it just shut down.
There's no log in Tomcat, the CPU/Memory are fines, there are no System.Exit in my code.
Anybody ever had this problem?
It happens at random, after 5-10 minutes. The application responds normally and sometime, boom.. stops working.
UPDATE : Still no clue. The Admin team will install the webapp on another box...

My script to start tomcat had last line tail -f catalina.out.
Sometime I did not kill this script, the shell then timed out and killed the script with all child processes, including tomcat.

This sounds like the JVM is crashing. Have you looked for a JVM crash log? It typically has a name like hs_err_pid*.log and is created in the JVM's working directory.
If you find a file like this and upload it, then we can probably help more.
Some questions:
Have you recently changed the version of Java you are using?
What is the exact version of Tomcat you are using?
Are you using Tomcat Native (the Apache Portable Runtime)?

Faced this issue recently.
Scenario : Tomcat started successfully but automatically gets shut down after 1 hour and sometimes this happened after 1 day and nothing is there in tomcat logs.
Issue : Actual issue was high memory usage and no free SWAP memory.
How I found the solution
If tomcat don't show any logs, then there must be something in system logs so, I checked /var/log/messages but since permission denied for me I tried /var/log/dmesg and got this
"Out of memory: Kill process 14606 (java) score 106 or sacrifice child".
In the output I noticed Swap Memory free 0 K. Ran top command to confirm the same. So, somehow there was a high memory usage which caused the OS to kill my tomcat process.
After spending hours finally got the reason.
ps -ef | grep tomcat showed that there were several tomcat processes running for the same application. It seems that, earlier tomcat shutdowns might not have taken successfully and the processes were not killed even after the shutdown due to some reason, which was causing the high memory usage.
So, killed all running tomcat processes using kill. SWAP memory got freed.
Started tomcat again, worked fine. :)

Recently I had this problem, If somebody faces the same issue in future I hope this will help.
Scenario: Tomcat shuts down without any logs or errors
Root Cause for my problem: synchronized method accessed from a task using TimerTask
I had a singleton class with a synchronized method accessed from various threads based on timer or user action
some times this method will take up to few minutes to complete. When TimerTask is waiting on this method for sometime (I guess timer is timed out /thread is killed or something is happening in the background) and the moment the lock on the method is released the tomcat is getting killed.
So I removed synchronized keyword and removed singleton and made some code changes for thread safety. Then the problem is gone.
How I found out: I had a log statement in the first line of synchronized method and everytime the tomcat shutdowns i found this message in the last few lines.
Regards,
Phanindra Kasturi

things to look for in debugging an issue like this:
Look at the logs directory ($TOMCAT_ROOT/logs) to make sure none of the log files have any stack traces
Look at the tomcat startup script to make check the location of the log files to see if the logs are not being written to another directory.
Another reason could be some other user/process could be issuing a kill -9 that could kill tomcat without giving it any chance to log errors.

another possibility is that some process was started this morning on the box that is binding to a port that your server requires.

Are your servlets or one of it's dependencies allowed to call System.exit()? (Not sure how locked down Tomcat VMs are in that sense)
I've had developers thinking it's ok to use exit(666); on detecting a non-invertable matrix (which isn't good, but sure as heck not fatal). Arrgh. Perhaps you have some similar culprit in your system?

I noticed CATALINA_OPTS in my path and that was set for a lower JVM size. Hence, the crash and no log trace of tomcat was found. The server automatically shutdown in less than 2 hrs.
check, CATALINA_OPTS or JAVA_OPTS -- these might have jvm settings. either increase them or comment them out and increase the swap memory.

“The Service on local computer started and then stopped ,Some services stop automatically if there are not in use by other services or programs.”
I gone through the problem i have tried so many ways to get out of the problem finally i got the solution as follows.
1) Click Run Command from start button.
2) Enter Services.msc then click OK,you will get all the services in your computer.
3) Select your service and right click on the service and select Properties
4) Goto Logon Properties and select Local System Account then click OK.
This will work.

Sometime it happens if some other program is running on the same port. For example Skype. Shut down that program before you start Tomcat.

try to clean your elipse projects because you could have tried to add another server which used port 8080 then when you try to execute the tomcat server externally that defaulty uses port 8080 the tomcat server automatically shutdowns after cleaning the project copy the new war file and paste it in bin it works fine
conclusion: when the server tries to use the port which has already been acquired you will see such type of issues.