COMP0019 Computer Systems
This database contains the 2018-19 versions of syllabuses.
Note: Whilst every effort is made to keep the syllabus and assessment records correct, the precise details must be checked with the lecturer(s).
The aim for this module is to have our advanced undergraduates develop a “whole-stack” understanding of the complex interactions among modern computer system hardware (specifically, a modern, multi-core CPU and its memory hierarchy), a modern operating system, and the applications that run atop them. These interactions dictate application correctness and performance. These fundamental principles will be taught in the concrete framework of the x86 CPU architecture and the Linux/UNIX operating system. Students should not only understand these fundamental principles, but be able to put them into practice in real C programs.
On successful completion of the module, a student will be able to:
- understand the C and Linux/UNIX programming environment, from the hardware (memory hierarchy, memory model between cores) to low-level operating system functionality (file and network I/O, process management, virtual memory system, program linking and loading);
- understand the interactions between hardware and the C and Linux/UNIX programming environment that affect application correctness and performance;
- design correct applications that perform well in the C and Linux/UNIX programming environment.
Availability and prerequisites
This module delivery is available for selection on the below-listed programmes. The relevant programme structure will specify whether the module is core, optional, or elective.
We regret that given the size of the 3rd-year undergraduate cohort, this module is not available to Affiliate Students, nor as an option to any student.
Programmes on which available:
There are no formal prerequsities.
This module teaches students topics in computer systems design and systems programming, with an emphasis on the C programming language, Intel CPU architecture, and UNIX/Linux operating system architecture. Topics covered will include:
- Machine-level representation of code and data (assembly language; how C constructs are compiled into x86 assembly language; machine-level representations of data types and machine and C arithmetic; stack frame structure in C on the x86; array layout in memory; pointer arithmetic)
- Use of the gdb debugger on C code in the Linux/UNIX environment
- Undefined behaviour in the C language specification and real C programs, and its consequences
- The memory hierarchy: registers, L1 caches, L2 caches, L3 caches, DRAM, SSD, disk; cache architectures; performance implications of caches on program performance
- Linking: static linking, relocatable object code, symbol resolution, loading executables, dynamic linking and shared libraries, position-independent code, interposition
- Processes, signals, context switches, exceptions, system call error handling, job control, process creation and management
- Virtual memory: address translation, memory mapping, dynamic memory allocation, memory-related bugs in C
- System I/O: filesystem I/O, system call interface and semantics
- Concurrent systems programming: threads in C on Linux/UNIX, x86 memory consistency model, races, deadlocks
An indicative reading list is available at http://readinglists.ucl.ac.uk/departments/comps_eng.html.
The module consists of lectures, individual programming courseworks, and one-on-one office hours (available throughout the term for students to use as they deem necessary). Systems principles cannot be fully grasped by reading and listening to lectures alone; they are only truly understood in depth by applying them in the building of significant systems. The module’s five substantial programming courseworks play this role.
This module is assessed as follows:
Written examination (2 hrs)
Programming courseworks (5 in the term)
In order to pass this module delivery, students must:
- achieve an overall weighted module mark of at least 40%; and
- achieve a mark of at least 30% in any components of assessment weighed ≥ 30% of the module.
Where a component comprises multiple assessments, the minimum mark applies to the overall component.