THE multiprogramming system
From Wikipedia, the free encyclopedia
The 'THE' multiprogramming system was a computer operating system designed by Edsger Dijkstra described in monographs in 1965-66 and published in 1968. THE is significant as it used the concept of layers as a structure.
Layer 0: was responsible for the multiprogramming aspects of the operating system. It decided which process was allocated to the CPU. It dealt with interrupts and performed the context switches when a process change was required. This is the lowest level.
Layer 1: was concerned with allocating memory to processes.
Layer 2: deals with inter-process communication and communication between the operating system and the console.
Layer 3: managed all I/O between the devices attached to the computer. This included buffering information from the various devices.
Layer 4: was where the user programs were stored.
Layer 5: was the overall control of the system (called the system operator).
[edit] See also
[edit] Bibliography
- E.W. Dijkstra, "The structure of the 'THE' multiprogramming system", Communications of the ACM 11(5):341–346, 1968. Dijkstra's manuscript EWD196 Full text (subscription)
