3.3. The 64-bit user process model
This section provides a brief explanation about the 64-bit user process model. The 64-bit user process model shares the same concept of segments and pages with the 32-bit user process model. The difference is the number of available segments in the address space. In the 64-bit user process model, an address space is composed of 232 segments, while it is composed of 24 = 16 segments in the 32-bit user process model.
Therefore, the 64-bit user process can address up to 1 EB (exabytes), which is easily returned by the following simple calculation:
232 segments x 256 [MB/segment] = 232 x 28 x 220 bytes = 232+8+20 = 260 = 1 EB
To address this tremendous huge space, the pointer type is defined as 64-bit in the ...
Get Developing and Porting C and C++ Applications on AIX now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
