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How to caputure HeapDumpOnOutOfMemoryError

I've deployed an application in tomcat 7.0.55 for testing.I want to capture whether "HeapDumpOnOutOfMemoryError" is occurring or not . Following are my JVM parameters.
JAVA_OPTS="-server -Xms512M -Xmx2048M -XX:PermSize=256m -XX:MaxPermSize=512m -XX:+UseConcMarkSweepGC -XX:+UseParNewGC -XX:ThreadStackSize=512 -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=/apps/dumps/"
I don't see any file under the directory. Does it create a file under the directory or i've to manually create a file to append ?

You can use it as below :
-XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=
You can also manually generate a memory map using jmap if you know the process id:
jmap -J-d64 -dump:format=b,file=
You can use JHat to analyze the dump.
jhat "path to dump file".
By default the heap dump is created in a file called java_pid.hprof in the working directory of the VM, as in the example above. You can specify an alternative file name or directory with the -XX:HeapDumpPath= option. For example -XX:HeapDumpPath=/disk2/dumps will cause the heap dump to be generated in the /disk2/dumps directory.

Check if it is a permissions issue to write to the configured folder /apps/dumps/.
For reference -
https://blog.gceasy.io/2015/08/14/how-to-capture-heap-dump-jmap/
https://blogs.oracle.com/LuzMestre/entry/how_to_collect_a_heap

Java Heap dump location , unix command line

I am facing a issue in which my heapdump is more than 2gb or maybe even 3gb is some cases , Now the problem is the heap dump gets created in a location (/home) which is of around 1gb only so after 1gb of heapdump the server gets deadlock(No other process can run)
I just want to change the location of the Heapdump.
I am running my code on unix server , and increasing the size of /home dir is not an option.
I have tried using -XX:HeapDumpPath but it is not working.
Please help me out here.

You should use -XX:HeapDumpPath='your location' according to http://www.oracle.com/technetwork/java/javase/tech/vmoptions-jsp-140102.html#DebuggingOptions

JAVA_OPTS="$JAVA_OPTS -Xdump:heap:label=/dumps/heapdump.%Y%m%d.%H%M%S.%pid.%seq.phd"
JAVA_OPTS="$JAVA_OPTS -Xdump:java:label=/dumps/javacore.%Y%m%d.%H%M%S.%pid.%seq.txt"
JAVA_OPTS="$JAVA_OPTS -Xdump:system:label=/dumps/core.%Y%m%d.%H%M%S.%pid.%seq.dmp"
JAVA_OPTS="$JAVA_OPTS -Xdump:snap:label=/dumps/Snap.%Y%m%d.%H%M%S.%pid.%seq.trc"
(Optional) JAVA_OPTS="$JAVA_OPTS -Xdump:what"
You can change the JAVA_OPTS env variable or simple add individual -Xdump cmds from where you are running the code.
like
java -d64 -Xdump:heap:label=/${INFA_ROOT}/temp/heapdump.%Y%m%d.%H%M%S.%pid.%seq.phd -Xmx4g ...rest of the arrgs.

How do I properly set the permgen size?

I have this VM with tomcat, java, and grails in it. I've been getting permgen errors so I looked around and found the solution:
set JAVA_OPTS="-Xms256m -Xmx1024m -XX:PermSize=512m -XX:MaxPermSize=512m"
I use SSH to access the vm and type the arguments above. I suppose that would fix the problem. Thing is, I wanted to make sure that I did it correctly. So I searched again on how I could check the current permSize and this is the solution I got:
jinfo -flag MaxPermSize 6444
6444 is the pid, and as a response, I got this.
-XX:MaxPermSize=85983232
Question: Is the value of the maxPermSize in bytes? because, if it is, then that would mean that the java_opts command didn't work. I am expecting to get 512m but 85983232 bytes = 82 mb.. Or am I seeing it wrong..? Can anybody enlighten me on this? D:

You have to change the values in the CATALINA_OPTS option defined in the Tomcat Catalina start file. To increase the PermGen memory change the value of the MaxPermSize variable, otherwise change the value of the Xmx variable.
Linux & Mac OS: Open or create setenv.sh file placed in the "bin" directory. You have to apply the changes to this line:
export CATALINA_OPTS="$CATALINA_OPTS -server -Xms256m -Xmx1024m -XX:PermSize=512m -XX:MaxPermSize=512m"
Windows:
Open or create the setenv.bat file placed in the "bin" directory:
set CATALINA_OPTS=-server -Xms256m -Xmx1024m -XX:PermSize=512m -XX:MaxPermSize=512m

Don't put the environment configuration in catalina.bat/catalina.sh. Instead you should create a new file in CATALINA_BASE\bin\setenv.bat to keep your customizations separate of tomcat installation.

So you are doing the right thing concerning "-XX:MaxPermSize=512m": it is indeed the correct syntax. You could try to set these options directly to the Catalyna server files so they are used on server start.
Maybe this post will help you!
How to make sure that Tomcat6 reads CATALINA_OPTS on Windows?

Completely removed from java 8 +
Partially removed from java 7 (interned Strings for example)
source

How to increase heap size for jBoss server

I have an upload files scenario in my project. When I'm trying to upload the large files it's giving me an OutOfMemory error. That error is related to Java heap size.
How can you increase the heap size in Java and which file do I need to alter for this? I'm using jboss 5.1 server for running my application.

You can set it as JVM arguments the usual way, e.g. -Xms1024m -Xmx2048m for a minimum heap of 1GB and maximum heap of 2GB. JBoss will use the JAVA_OPTS environment variable to include additional JVM arguments, you could specify it in the /bin/run.conf.bat file:
set "JAVA_OPTS=%JAVA_OPTS% -Xms1024m -Xmx2048m"
However, this is more a workaround than a real solution. If multiple users concurrently uploads big files, you'll hit the same problem sooner or later. You would need to keep increasing memory for nothing. You should rather configure your file upload parser to store the uploaded file on temp disk instead of entirely in memory. As long as it's unclear which parser you're using, no suitable answer can be given. However, more than often Apache Commons FileUpload is used under the covers, you should then read the documentation with "threshold size" as keyword to configure the memory limit for uploaded files. When the file size is beyond the threshold, it would then be written to disk.

On wildfly 8 and later, go to /bin/standalone.conf and put your JAVA_OPTS there, with all you need.

Edit the following entry in the run.conf file. But if you have multiple JVMs running on the same JBoss, you might want to run it via command line argument of -Xms2g -Xmx4g (or whatever your preferred start/max memory settings are.
if [ "x$JAVA_OPTS" = "x" ]; then
JAVA_OPTS="-Xms2g -Xmx4g -XX:MaxPermSize=256m -Dorg.jboss.resolver.warning=true

Use -Xms and -Xmx command line options when runing java:
-Xms<size> set initial Java heap size
-Xmx<size> set maximum Java heap size
For more help type java -X in command line.

I have mentioned the configuration changes needed for the increase of heap size in Windows or Linux environments.
Linux:
bin/standalone.conf
Check for the following line,
JAVA_OPTS
and change it accordingly to suit your heap size needs
-Xms1303m: initial heap size in megabytes
-Xmx1303m: maximum heap size in megabytes
JAVA_OPTS="-Xms1024M -Xmx2048M -XX:MaxPermSize=2048M -XX:MaxHeapSize=2048M"
Windows:
bin/standalone.conf.bat
JAVA_OPTS="-Xms1024M -Xmx2048M -XX:MaxPermSize=2048M -XX:MaxHeapSize=2048M"
Now restart the server and it will work without prompting any heap size errors.
For more information you can refer this link below.
https://access.redhat.com/documentation/en-us/jboss_enterprise_application_platform/5/html/getting_started_guide/adjust_memory_settings

Look in your JBoss bin folder for the file run.bat (run.sh on Unix)
look for the line
set JAVA_OPTS, (or just JAVA_OPTS on Unix) at the end of that line add -Xmx512m. Change the number to the amount of memory you want to allocate to JBoss.
If you are using a custom script to start your jboss instance, you can add the set JAVA_OPTS option there as well.

In my case, for jboss 6.3 I had to change JAVA_OPTS in file jboss-eap-6.3\bin\standalone.conf.bat and set following values -Xmx8g -Xms8g -Xmn3080m for jvm to take 8gb space.

Add following option in jboss in bin/standalone.conf.bat
set "JAVA_OPTS=-Xms1G -Xmx1G -XX:MetaspaceSize=96M -XX:MaxMetaspaceSize=1024m"

What to change?
set "JAVA_OPTS=%JAVA_OPTS% -Xms1024m -Xmx2048m"
Where to change? (Normally)
bin/standalone.conf(Linux) standalone.conf.bat(Windows)
What if you are using custom script which overrides the existing settings? then?
setAppServerEnvironment.cmd/.sh (kind of file name will be there)
More information are already provided by one of our committee members!
BalusC.

You can increase or set the heap size configuration i.e. -Xms/Xmx or any other JVM options in the JBoss application server in JAVA_OPTS JVM options in standalone.conf(Linux) & standalone.conf.bat file in Windows.
JAVA_OPTS="-Xms2048M -Xmx2048M"

How to increase Java heap space for a tomcat app

There are lots of questions that ask this or a similar question.
They all give the command that has to be executed, what I don't understand is where do I write this command. I want to permanently increase the heap space for my tomcat apps.
I read this page http://javahowto.blogspot.com/2006/06/6-common-errors-in-setting-java-heap.html and it says under the Tomcat section
Stop Tomcat server, set environment variable CATALINA_OPTS, and then restart Tomcat. Look at the file tomcat-install/bin/catalina.sh or catalina.bat for how this variable is used. For example,
set CATALINA_OPTS=-Xms512m -Xmx512m (Windows, no "" around the value)
export CATALINA_OPTS="-Xms512m -Xmx512m" (ksh/bash, "" around the value)
setenv CATALINA_OPTS "-Xms512m -Xmx512m" (tcsh/csh, "" around the value)
So I replaced the line
set CATALINA_OPTS=
with
set CATALINA_OPTS=-Xms512m -Xmx512m
But I still get the error.
javax.servlet.ServletException: Servlet execution threw an exception
root cause
java.lang.OutOfMemoryError: Java heap space
java.lang.reflect.Array.multiNewArray(Native Method)
java.lang.reflect.Array.newInstance(Array.java:90)
nom.tam.util.ArrayFuncs.newInstance(ArrayFuncs.java:1028)
nom.tam.fits.ImageData.read(ImageData.java:259)
nom.tam.fits.Fits.readHDU(Fits.java:573)
controller.UploadServlet.retreiveFITSFileFields(UploadServlet.java:206)
controller.ScanServerFiles.doPost(ScanServerFiles.java:39)
javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)

There is a mechanism to do it without modifying any files that are in the distribution. You can create a separate file %CATALINA_HOME%\bin\setenv.bat or $CATALINA_HOME/bin/setenv.sh and put your environment variables there. Further, the memory settings apply to the JVM, not Tomcat, so I'd set the JAVA_OPTS variable instead:
set JAVA_OPTS=-Xmx512m

First of all you cannot change the memory settings only for a tomcat application but rather for all tomcat instance.
If you are running tomcat from console (using startup.bat) you'll need to edit catalina.bat and play around with CATALINA_OPTS. For example:
set CATALINA_OPTS=-Xms512m -Xmx512m
Restarting tomcat will apply the new settings.
If you are still getting OutOfMemoryError you need to know how much memory does your application need at that particular moment (nom.tam.util.ArrayFuncs...). You'll either have to optimize the application or simply increase the memory provided to tomcat.

Your change may well be working. Does your application need a lot of memory - the stack trace shows some Image related features.
I'm guessing that the error either happens right away, with a large file, or happens later after several requests.
If the error happens right away, then you can increase memory still further, or investigate find out why so much memory is needed for one file.
If the error happens after several requests, then you could have a memory leak - where objects are not being reclaimed by the garbage collector. Using a tool like JProfiler
can help you monitor how much memory is being used by your VM and can help you see what is using that memory and why objects are not being reclaimed by the garbage collector.

Open the server tab in eclipse
right click open
click on open lauch configuration
Go to arguments
Here you can add in VM arguments after endorsed
-Xms64m -Xmx256m

You need to add the following lines in your catalina.sh file.
export CATALINA_OPTS="-Xms512M -Xmx1024M"
UPDATE : catalina.sh content clearly says -
Do not set the variables in this script. Instead put them into a script setenv.sh in CATALINA_BASE/bin to keep your customizations separate.
So you can add above in setenv.sh instead (create a file if it does not exist).

Easiest way of doing is: (In Linux/Ububuntu e.t.c)
Go to tomcat bin directory:
cd /opt/tomcat8.5/bin
create new file under bin directory "setenv.sh" and save below mention entries in it.
export CATALINA_OPTS="$CATALINA_OPTS -Xms512m"
export CATALINA_OPTS="$CATALINA_OPTS -Xmx2048m"
export CATALINA_OPTS="$CATALINA_OPTS -XX:MaxPermSize=256m"
and issue command:
./catalina.sh run
In your catalina log file you can see entry like this:
INFO [main] VersionLoggerListener.log Command line argument: -Xms512m
INFO [main] VersionLoggerListener.log Command line argument: -Xmx2048m
INFO [main] VersionLoggerListener.log Command line argument: -XX:MaxPermSize=256m
Which confirms that above changes took place.
Also, the value of "Xms512m" and "-Xmx2048m" can be modified accordingly in the setenv.sh file.
Startup of tomcat could be done in two steps as well.
cd /opt/tomcat8.5/bin
Step #1
run ./setenv.sh
Step #2
./startup.sh
If you're using systemd edit:
/usr/lib/systemd/system/tomcat8.service
and set
Environment=CATALINA_OPTS="-Xms512M -Xmx2048M -XX:MaxPermSize=256m"

if you are using Windows, it's very simple. Just go to System Environnement variables (right-clic Computer > Properties > Advanced System Parameters > Environnement Variables); create a new system variable with name = CATALINA_OPTS and value = -Xms512m -Xmx1024m. restart Tomcat and enjoy!

For Windows Service, you need to run tomcat9w.exe (or 6w/7w/8w) depending on your version of tomcat.
First, make sure tomcat is stopped. Then double click on tomcat9w.exe. Navigate to the Java tab. If you know you have 64 bit Windows with 64 bit Java and 64 bit Tomcat, then feel free to set the memory higher than 512. You'll need to do some task manager monitoring to determine how high to set it. For most apps developed in 2019... I'd recommend an initial memory pool of 1024, and the maximum memory pool of 2048. Of course if your computer has tons of RAM... feel free to go as high as you want.
Also, see this answer: How to increase Maximum Memory Pool Size? Apache Tomcat 9

you can set this in catalina.sh as CATALINA_OPTS=-Xms512m -Xmx512m
Open your tomcat-dir/bin/catalina.sh file and add following line anywhere -
CATALINA_OPTS="$CATALINA_OPTS -Xms1024m -Xmx3024m"
and restart your tomcat

Just set this extra line in catalina.bat file
LINE NO AROUND: 143
set "CATALINA_OPTS=-Xms512m -Xmx512m"
And restart Tomcat service