Develop Reference

Apache Tomcat Server OutOfMemoryError [duplicate]

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

JAVA set Garbage collection options

I want to get GC logs from a program which runs on top of JVM. I know its possible to get those using
-Xloggc:GCLog.txt -verbose:gc -XX:+PrintGCDateStamps -XX:+UseSerialGC
parameters when running the application using
java -jar "jar_file".
But in this case I can't run the program in this manner by giving arguments, instead is there a way to specify them before running the application?
For an example we can set Xmx, Xms values using export
JVM_MEM_OPTS="-Xms100m -Xmx100m"
before running the java application.) Is there a similar way to specify GC parameters before running the application.
Thank you

For an example we can set Xmx, Xms values using export
JVM_MEM_OPTS="-Xms100m -Xmx100m"
This way is not standard and not referenced in the Java documentation.
JVM_MEM_OPTS, JAVA_OPTS or any environment variable will set the JVM options only because the tool/program that you use to start the JVM transmit it in the JVM options of the java command that is executed.
For example JAVA_OPTS is recognized in the Tomcat scripts (especially catalina.sh/bat).
-Xms100m -Xmx100m as -Xloggc:GCLog.txt -verbose:gc -XX:+PrintGCDateStamps -XX:+UseSerialGC are JVM options.
If you don't want to pass directly these options in the java command, you have to do as the tools that allows to use a custom environment variable : create a script (specific to the OS) that uses this environment variable as value of the JVM options such as (linux way):
java $JAVA_OPTS -jar "jar_file"

How to set the -Xmx for JRE when start running JMeter

When running JMeter, java server has the -Xmx value of only 512 MB. I tried to change it via following code in the jmeter.bat.sh file.
set HEAP=-server -Xms512m -Xmx6144m
set NEW=-XX:NewSize=512m -XX:MaxNewSize=6144m
also tried this:
set HEAP= -Xms512m -Xmx6144m
set NEW=-XX:NewSize=512m -XX:MaxNewSize=6144m
By checking the process after while JMeter is running I can see that java -sever doesn't recognize this setting.

If you are running jmeter startup script on Linux the syntax will be different, i.e:
HEAP="-Xms512m -Xmx6G"
as SET command is something Windows-specific
Alternatively you can define JVM_ARGS environment variable value like:
JVM_ARGS="-server -Xms512m -Xmx6G" && export JVM_ARGS
this way you won't need to edit files and/or restart JMeter.
Finally, you can launch JMeter jar directly like:
java -server -Xms512m -Xmx6G -jar ApacheJMeter.jar
See the following reference material:
Tuning Java Virtual Machines (JVMs)
JMeter Best Practices
9 Easy Solutions for a JMeter Load Test “Out of Memory” Failure

How to use the Xmx command? (JVM Heap memory)

I'm new in the Oracle world and I'm working with Oracle Identity Analytics (OIA). In the test environment everything is ok, but in production environment i'm getting an "java.lang.OutOfMemoryError", so when I checked the Xmx and Xms I saw that I had Xmx:512m and Xms:512m, that's why I'm trying to modify the Xmx value.
I want to modify the Xmx and Xms values so I wrote the following line in my PuTTY:
$ java -Xmx1024m
But the PuTTY shows me the following:
Usage: java [-options] class [args...] (to execute a class) or
java [-options] -jar jarfile [args...] (to execute a jar file)
where options include:...
Seems like I'm forgetting something after "Xmx1024m", but what? Well, now I know I'm forgetting Jar file, Class or App name but I have no idea how to get any of those things. I tried putting "$AdminServer" after "Xmx1024m" but it didn't work.
My Java version is 1.6.0_45 Oracle JRockit build R28 and the Operative Systems is Linux Server 6.5.
Regards!

You have to pass filepath to execute. Of course, you can run
java -Xmx1024m
but Java doesn't know what file should be executed

You will have to pass the program-name/filename/jar-name,whatever it is,with path for which you want to set/reset the java heap size.
e.g
java -Xms1024M -Xmx2048M -jar xi.jar
java -Xmx64m ${PROGRAM_NAME}
Hope this helps you.Or to help you better,could you please tell us what exactly is your scenario?

Problems with java heap space, how to increas the heap size?

I'm running a ".bat" file which points to asant:
C:\Sun\SDK\bin\asant Startbds
asant again points to a xml file i've got, build.xml:
<target name="Startbds" description="Start bds">
This has been fine for now, but now i have added more data, which leads to an out of memory error:
java.lang.outOfMemoryError: Java heap space
So i've tried to increase the heap space by various methods i've found while searching around for a solution:
cmd: set ANT_OPTS=-Xms512m -Xmx512m (did not work, same error message)
Editing the asant.bat where i edited the line "-set ANT_OPTS" from
.
set ANT_OPTS="-Dos.name=Windows_NT" -Djava.library.path=%AS_INSTALL%\lib;%AS_ICU_LIB%;%AS_NSS%" "-Dcom.sun.aas.installRoot=%AS_INSTALL%" "-Dcom.sun.aas.instanceRoot=%AS_INSTALL%" "-Dcom.sun.aas.instanceName=server" "-Dcom.sun.aas.configRoot=%AS_CONFIG%" "-Dcom.sun.aas.processLauncher=SE" "-Dderby.root=%AS_DERBY_INSTALL%"
TO
set ANT_OPTS="-Xms512m -Xmx512m" "-Dos.name=Windows_NT" -Djava.library.path=%AS_INSTALL%\lib;%AS_ICU_LIB%;%AS_NSS%" "-Dcom.sun.aas.installRoot=%AS_INSTALL%" "-Dcom.sun.aas.instanceRoot=%AS_INSTALL%" "-Dcom.sun.aas.instanceName=server" "-Dcom.sun.aas.configRoot=%AS_CONFIG%" "-Dcom.sun.aas.processLauncher=SE" "-Dderby.root=%AS_DERBY_INSTALL%"
but this gave me the error message:
"Invalid initial heap size: -Xms512m -Xmx512m
Could not create the Java virtual machine."
Anyone got an idea of how i should increase the heapsize?
And maybe also give a pointer to where i can find a tool to watch the heapsize.
Thanks in advance.

By using "-Xms512m -Xmx512m" you gave a single argument. -Xms expects the minimum heap size to be specified by the rest of the argument. So you defined the minimum heap size to be "512m -Xmx512m", which is not a valid value.
You will want to provide those switches as two arguments:
set ANT_OPTS=-Xms512m -Xmx512m "-Dos.name=Windows_NT" ...

I think that if you're in windows, you don't need the double quotes in your set.
Here is an example I saw somewhere:
set ANT_OPTS=-Xms512m -Xmx512m (Windows)
export ANT_OPTS="-Xms512m -Xmx512m" (ksh/bash)
setenv ANT_OPTS "-Xms512m -Xmx512m" (tcsh/csh)
As for monitoring heap usage, if you are using the most recent JDK on Windows, you should have Sun's VisualVM.

In eclipse -> window -> preferences -> Tomcat -> JVM Setting -> Append to JVM Parameters:
-XX:MaxPermSize=512m
-Xms512m
-Xmx512m