OracleAS 10.1.2 on 32 bit vs. 64 bit
By M&S Consulting (Ashok) on Apr 13th, 2009
Filed Under Technical Tips // Tags: oracle application server, oracle portal
Filed Under Technical Tips // Tags: oracle application server, oracle portal
Some people get excited about the prospects of running Oracle Application Server (10.1.2) on a 64-bit OS. However, just to be clear here, even if you go through the patching to get the install completed, you will still only be running OracleAS in 32-bit mode.
By the way, if you have reasons for really wanting to run OracleAS on a 64-bit OS, I would be interested in hearing a compelling argument.
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Jun 19, 2009
The maximum theoretical heap limit for the 32-bit JVM is 4G. Due to various additional constraints such as available swap, kernel address space usage, memory fragmentation, and VM overhead, in practice the limit can be much lower. On most modern 32-bit Windows systems the maximum heap size will range from 1.4G to 1.6G. On 32-bit Solaris kernels the address space is limited to 2G. On 64-bit operating systems running the 32-bit VM, the max heap size can be higher, approaching 4G on many Solaris systems.
As of Java SE 6, the Windows /3GB boot.ini feature is not supported.
If your application requires a very large heap you should use a 64-bit VM on a version of the operating system that supports 64-bit applications. See Java SE Supported System Configurations for details.