Introduction to computer architecture and operating systems (2017/2018)

Learning outcomes

Knowledge and understanding: students wiil learn the theory and practice to realize an algorithm in hardware, exploring a spectrum of options ranging from dedicated specialized devices to programs on a general-purpose processor; they will understand how a processor works and how an high-level program is translated into machine language and then executed; they will understand the organization of a computer system and of the operating systems running on it, with the related issues of correctness and efficiency.

Capabilities to apply knowledge and understanding: the students will be able to design specialized hardware for simple algorithms; translate simple programs from an high-level specification to machine language; write shell scripts using system calls in C in the UNIX environment; manage an information system, especially for what the installation and maintenance of applications and resources is concerned.

Syllabus

Computer Architecture.

Fundamentals: information coding, Boolean functions, arithmetic.

Digital design: combinational circuits, sequential circuits, special purpose architectures (control unit + data path), programmable units.

Computer architecture: basic principles, instruction set, processor, memory hierarchy, I/O organization.

Practical exercises: assembly programming of LC-3 architecture.


Operating systems.

Evolution and role of the operating system. Architectural concepts. Organization and functionality of an operating system.

Process Management: Processes. Process status. Context switch. Process creation and termination. Thread. User-level threads and kernel-level threads. Process cooperation and communication: shared memory, messages. Direct and indirect communication.

Scheduling: CPU and I/O burst model. Long term, short term and medium term scheduling. Preemption. Scheduling criteria. Scheduling algorithm: FCFS, SJF, priority-based, RR, HRRN, multiple queues with and without feedback. Algorithm evaluation: deterministic and probabilistic models, simulation.

Process synchronization: data coherency, atomic operations. Critical sections. SW approaches for mutual exclusion: Peterson and Dekker's algorithms, baker's algorithm. HW for mutual exclusion: test and set, swap. Synchronization constructs: semaphores, mutex, monitor.

Deadlock: Deadlock conditions. Resource allocation graph. Deadlock prevention. Deadlock avoidance. Banker's algorithm. Deadlock detection e recovery.

Memory management: Main memory. Logical and physical addressing. Relocation, address binding. Swapping. Memory allocation. Internal and external fragmentation. Paging. HW for paging: TLB. Page table. Multi-level paging. Segmentation. Segment table. Segmentation with paging.

Virtual memory: Paging on demand. Page fault management. Page substitution algorithms: FIFO, optimal, LRU, LRU approximations. Page buffering. Frame allocation: local and global allocation. Thrashing. Working set model. Page fault frequency.

Secondary memory. Logical and physical structure of disks. Latency time. Disk scheduling algorithms: FCFS, SSTF, SCAN, C-SCAN, LOOK, C-LOOK. RAID.

File System: file, attributes and related operation. File types. Sequential and direct access. Directory structure. Access permissions and modes. Consistency semantics. File system structure. File system mounting. Allocation techniques: adjacent, linked, indexed. Free space management: bit vector, lists. Directory implementation: linear list, hash table.

I/O subsystem: I/O Hardware. I/O techniques: programmed I/O, interrupt, DMA. Device driver and application interface. I/O kernel services: scheduling, buffering, caching, spooling.

Practical exercises: system-level and shell programming with C.

Assessment methods and criteria

Written test for the theoretical part with questions and exercises (3/4 of the final grade).
Programming projects and written test for the laboratory (1/4 of final grade).

STUDENT MODULE EVALUATION - 2017/2018