Unix Tipz & Tricz

By default, Windows can address a total of 4 gigabytes (GB) of virtual address space. By default, 2 GB of this is reserved for the kernel (operating system), and 2 GB is reserved for User mode programs such as Exchange.

When we put a /3GB switch into the boot.ini file of the operating system, we reallocate the virtual address space distribution to give User mode programs 3 GB of space and limit the kernel to 1 GB. The /3GB switch is only required on computers that contain mailbox stores or public folder stores. This switch is not recommended on computers that do not have mailbox stores or public folder stores.

We can only use the /3GB switch with the following operating systems:-