Can not startup TomEE in KNIME Server

I have installed KNIME Server on my server, web server can not start up, the following is error message in the log file.

I want to know, where can I modify the memory size?

Thanks.

Exception in thread “main” java.lang.OutOfMemoryError: unable to create new native thread
at java.lang.Thread.start0(Native Method)
at java.lang.Thread.start(Thread.java:717)
at org.apache.tomee.catalina.Warmup.(Warmup.java:204)
at org.apache.tomee.catalina.TomcatLoader.initialize(TomcatLoader.java:147)
at org.apache.tomee.catalina.ServerListener.lifecycleEvent(ServerListener.java:168)
at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:94)
at org.apache.catalina.util.LifecycleBase.setStateInternal(LifecycleBase.java:395)
at org.apache.catalina.util.LifecycleBase.init(LifecycleBase.java:108)
at org.apache.catalina.startup.Catalina.load(Catalina.java:632)
at org.apache.catalina.startup.Catalina.load(Catalina.java:655)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.apache.catalina.startup.Bootstrap.load(Bootstrap.java:309)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:492)

Hi.

By default the KNIME Server Tomcat application requires 2Gb RAM. How much do you have available on your system? You can find that in the Task manager in Windows, or by running free -h under Linux.

Thanks for your reply.

My OS is Centos, free memory is more than 2G.
I check the setenv.sh, and have below line
export CATALINA_OPTS="-Xmx2048M -server"
I update the size, but can not startup tomee.

The error message means that the java process cannot allocate more memory from the OS so either your system is low on memory or you are accidentally using a 32bit java installation. You can check this by calling java -version.