Operating System- System View (3.1 Process Management (3.1.2 Single…
Operating System- System View
3.1 Process Management
Job Scheduler: The goal is to put jobs in a sequence that uses all system’s resources as fully as possible and strives for balanced mix of jobs with large I/O interaction and jobs with lots of computation.
CPU Scheduler: Interactive operating systems employ some level of feedback in which the task with which the user is working receives higher priority.
3.1.1 Process Concept
• New - Process being created
• Running - Instructions are being executed
• Waiting - Process waiting for event to occur
• Ready - Process waiting to be assigned to a processor
• Terminated - Process finish execution
3.1.2 Single Tasking
3.1.3 Multi Tasking
Multiprogramming 2. Time Sharing 3. Cooperative multitasking
3.2 Memory Management
3.2.1 Memory Hierarchy
Register, Cache, Main memory, Distributed memory, Tapes
3.2.2 Physical Memory
3.2.3 Virtual memory requirement
Relocation, protection, sharing, logical organization, physical organization
3.3 I/O Management
3.3.1 I/O System Organization
3.3.2 I/O Communication Technique
Direct I/O with polling
Interrupt Drive I/O
3.3.3 Direct Memory Access
DMA is efficient technique when large volumes of data are to be moved.
Buffer is temporary memory or storage used to adjust for the speed differential between adjacent devices.
3.4 Operating System Protection and Security
3.4.1 User Authentication
3.4.2 Basic Resource Protection
CPU and memory protection