Problem Program Address Space Switching
Original Publication Date: 1980-Jan-01
Included in the Prior Art Database: 2005-Feb-12
This improvement extends a 16-bit address architecture, such as that found in the IBM Series/1, to permit the execution of user programs larger than 64 KB (kilobytes) without supervisor intervention. In multiple address space systems, the user may be assigned multiple address spaces for his processes. It is desirable to have problem program instructions to move data between these address spaces. It is also desirable to be able to transfer control without supervisor intervention between the address spaces owned by a single user. By extending the architecture in this way, one enables the user to build very large task sets (larger than 64 KB) and one also significantly reduces system overhead. All of these inter-address space instructions should be extensions of existing instructions.