Pilot
Q: How do the requirements of the Pilot operating system differ from the systems we have read about so far, and how does the design of Pilot reflect those differences?
- First PC
- single user
- single language
- single address space
- no time-sharing
- Defensive protection
- Why we use UNIX instead of Pilot in PC today?
- Even we don't have many users, we have so many things/apps running in our laptop.
Feature of Mesa language
- Object oriented (Pointer not exist)
- Single address space (No H/W protection)
- Strong type check
Hints
- Memory mapped file, pages used, can be moved
- OS trust the app hints
- No incentive for lying
Major components of Pilot
Questions
Design decisions from Pilot that were motivated from the goal (an OS for a personal computer)
- single-language
- single-user system
- with only limited features for protection and resource allocation.
What design assumption does not work well for today?
- It assumes that maliciousness is less serious.