Java 32 Bits with PAE Kernel + SO 32 bits and CPF 64 Bits

Question

I'm facing a problem in my application using JBOSS 4.2.3GA. We have approximately 20 users online and is usual the cpu run to 95%, 99%. We search for problem in application using jmeter and other tests and we don't find a point or loop that can be causing this problem.

We have an historic problem with the organization responsable for my client data center. So, i started to look its architecture and i read in some site about "32 bits java x 64 bits java" and "32 bits SO vc 64 bits SO" and come with some question and hope someone can help me.

the production machine is - 1 vCPU Intel Xeon E5506 2.13Ghz 5120Mb RAM 1 HD 80Gb (ark.intel.com/products/37096/Intel-Xeon-Processor-E5506-4M-Cache-2_13-GHz-4_80-GTs-Intel-QPI) - redhat 32 bits (kernel: 2.6.18-274.7.1.el5PAE) - java 32 bits.

The question is:

1. The cpu is 64 bits, the SO is 32 bits and java 32 bits. we will get a considerated value change de SO and JAVA to 64 bits?
2. i read about some problems using java 32 bits with PAE kernel. (https://kb.groundworkopensource.com/display/SUPPORT/Using+the+32-bit+PAE+kernel+can+cause+JAVA+errors) and a benchmark test using apache server (http://www.phoronix.com/scan.php?page=article&item=ubuntu_32_pae&num=1). can it be a problem?
3. The version of jboss is old, we will get a considerated value change the version of jboss to a newer one?

If someone can help me with something i forget, please say it :)

Thanks in advance

Answer 1

The cpu is 64 bits, the SO is 32 bits and java 32 bits. we will get a considerated value change de SO and JAVA to 64 bits?

To use 64-bit processing you need to have

• a 64-bit capable processor.
• a 64-bit OS
• a 64-bit JVM.

In your case you need to upgrade your OS and JVM.

I suspect your production application is doing something you are not testing for. I suggest you profile you application in production to find out what it is you are not testing.

The version of jboss is old, we will get a considerated value change the version of jboss to a newer one?

If your profiling points to a performance bottleneck in JBoss, upgrading it might help. Otherwise, I would assumes its your application.