Accessing more than 2.0 GB of memory on Windows XP

 

This section describes necessary settings to get access to more than 2.0 GB of memory on Windows XP within a V5 process.

Background

By default, Version 5 processes on Windows can allocate up to 2.0 GB of memory for storing data and code. The 4 GB address space offered by the operating system being split in two areas of 2 GB each, first 2 GB for user mode, 2 other GB being reserved by the kernel. On Windows XP, it is possible to increase  the default allocation capabilities up to 3.0 GB (3 GB for user mode, 1 GB reserved for kernel). Such capability requires additional tunings in order to be effective :

Operating System requirements

Version 5 required customizations

Since R14, the Version 5 main executable is already "Large Address Space Aware",  to get access to the 3GB of address space .

To disable the use of the "Large Address Space"  :

Note: CNEXT.exe is given here as an example, one should replace it by the appropriate Version 5 executable.

 

To go back to the initial behavior after disabling the large address space capability, one can use :

 

Additional Operating System considerations