I am trying to run some .jar file but I am getting below error. The system has 20 gb of ram and my Xms and Xmx values are -Xms2048m -Xmx4096m
Are these values are too big or there is another thing causing this error?
java.lang.OutOfMemoryError: Java heap space
EDIT:
java -jar -Xms2048m -Xmx4096m /Filereadertest.jar
I am using java 1.7.51
Java HotSpot(TM) 64-Bit Server VM
Are these values are too big or there is another thing causing this error?
The default for the server JVM is 1/4 of main memory or 5 GB, so you are actually decreasing the maximum by setting this.
You could set it to 80% of main memory such as -Xmx16G
Along with JRE version and architecture, heap space per process also depends upon the operating system in use.
For example, Windows 32-bit allows maximum 2 GB memory per process, which also includes size for stacks, libraries and other stuff. So in practice, we generally get 1.25 GB memory.
Have a look at:
Oracle's Guidelines for Heap Space Sizing
Related
Help!
I'm getting this error in my processing sketch:
java.lang.OutOfMemoryError.Java heap space
My sketch runs a lot of .png image sequences simultaneously, using depth data from the kinect. I think I just need to increase my max heap space memory available in Java or Java Virtual Machine, but I can't figure out how to do that. The information I can find requires a level of understanding of java that's beyond my skill level. Would anyone be willing to post a walk-though for mac or a link to one? Thanks!
You can use the following command line option.
-Xms<size> set initial Java heap size
-Xmx<size> set maximum Java heap size
More information here
If you are running you program from command line use,
java -Xms256m -Xmx4096m <main class>
Maximum and starting memory allocated by the JVM can be parametrized by vmargs
-Xmx : maximum memory that will be allocated
-Xms: starting memory
example: with vmargs -Xms512m -Xmx2g your jvm will start with 512Mb of allocated memory and increase it to a maximum of 2Gb
I am trying to set the Xmx parameter when starting up a program. If I set it to 1408M, the JRE starts up fine. If I set it to 1536M, I get
"Could not create the java virtual machine".
I understand that it's trying to reserve consecutive memory space, but the machine I'm running on has 16GB of RAM and 13GB of that is currently free. The program I'm running is running out of heap space and crashing on me. Is there anything I can do to fix this?
Use a 64bit JVM. The 32bit JVM is limited (depending on the OS) to at most 3 GByte (on linux I have a limitation of about 1.5 GByte).
32-bit JVMs are limited to roughly 1.5 GB of heap space due to addressing constraints and the need for memory for other reasons. On Windows 2 GB is assigned to the process, and 0.5 is used for non-heap memory. If you can use PAE on Windows Server or possibly Linux, you can address up to 3 or 4 GB, respectively.
Otherwise use a 64-bit JVM.
I am getting out of memory errors on a jboss webapp and have tweaked memory settings and when values seem larger than 1024 on specific settings I get a java run time error could not allocate memory. Does anyone know what the max values I can use below on a 32bit jdk?
set "JAVA_OPTS=-Xms128M -Xmx512M -XX:MaxPermSize=256M"
You can allocate more than 1GB for heap on 32-bit JDK (sounds like something that depends on the JVM implementation, but according to Google it's around 1.5GB).
You probably don't have enough available memory on your server. Free up some memory and have a try.
I have got a problem. My program is really big and java is throwing OutOfMemoryException.
In .bat file, I have got the following:
java -server -Dfile.encoding=UTF-8 -Xmx1500m -Xbootclasspath/p:../libs/l2ft.jar -cp config/xml;../libs/*; l2ft.gameserver.GameServer
Java is using 6 GB of my RAM, next 6 GB is not used.
I typed System.getProperty("sun.arch.data.model"); and it says that I am using 64-bit JVM.
You have set the maximum heap size to 1500m and while the JVM can use a little more than that ~200 MB, that's all you limited the process to.
Try instead to limit your progress to around 5 GB. (You want to leave some memory for overhead and the OS)
-mx5g
Make the options before Xbootclasspath this:
java -XX:MaxPermSize=512m -server -Dfile.encoding=UTF-8 -Xmx8g -XX:+UseCompressedOops
This will make it use more memory and will also make sure it uses as little memory as possible to address the objects in a 64bits machine.
The -XX:MaxPermSize=512m makes the perm gem space larger (which you will probably need as you're using a lot of heap memory) and the -XX:+UseCompressedOops will make it use 32bits addressing for objects, instead of 64bits, as a 8gb heap can be correctly addressed with 32bits, so it makes you use less memory for allocating objects.
How much -XX:MaxPermSize size i can mention for 4GB and 8GB Ram. Here are the other detalis of my system
OS:-window XP(32 bit)
RAM:-4 GB
java_opt- -Xms1536m -Xmx1536m //(mentioned as environment variable):
tomcat version:-6.0.26
I have another system with 8GB ram with other details exactly same . Yes os is 64 bit Window 7.
Along with this also let me know what can be the max value for -Xmx parameter for both the systems?
It would be great if some body can tell me the calculation to arrive at the figure so that we dont have to cram this figure but we can logically calculate based on RAM ssytem is having?
I have really seen people getting permgen error or heap error but every body keeps on playing with this paramters until they come to figure that resolve the issue.
According to IBM document, application runs with a minimum heap usage of 40%, and a maximum heap usage of 70%.
Refer to this information
Why can't I get a larger heap with the 32-bit JVM?
Max amount of memory per java process in windows?
Sizing the Java heap