The public defense of Meng Liu’s doctoral thesis in Computer Science and Engineering

Doctoral thesis and Licentiate seminars

Datum: 2017-06-20
Tid: 09.15
Plats: Mälardalen University, room Gamma, Västerås.

The public defense of Meng Liu’s doctoral thesis in Computer Science and Engineering will take place at Mälardalen University (Västerås Campus) room Gamma, at 09.15 AM on June 20, 2017.

The title of the thesis is “Real-Time Communication over Wormhole-Switched On-Chip Networks”.

The faculty examiner is Professor Christian Fraboul, University of Toulouse; and the examining committee consists of Associate Professor Ingo Sander, KTH Royal Institute of Technology ; Associate Professor Martina Maggio, Lund University; Adjunct Professor Tiberiu Seceleanu, MDH.

Reserve; Professor Jan Carlson, MDH.

The doctoral thesis has serial number 232.

Abstract

In a modern industrial system, the requirement on computational capacity has increased dramatically, in order to support a higher number of functionalities, to process a larger amount of data or to make faster and safer run-time decisions. To cope with the increased computational requirements, many-core processors are gaining more and more attention nowadays. On a many-core processor, a large number of software programs can be executed in parallel, which can thus boost the computational performance. The Network-on-Chip (NoC) is an interconnection medium between intellectual property cores on a massively parallel platform, which is commonly used in many-core processors or system-on-chips in general.

Real-time embedded systems have been widely utilized for decades. In addition to the correctness of functionalities, timeliness is also an important factor in such systems. Violation of specific timing requirements can result in performance degradation or even fatal problems. While executing real-time applications on many-core processors, the timeliness of a NoC, as a communication subsystem, is essential as well. Unfortunately, many real-time system designs over-provision resources to guarantee the fulfillment of timing requirements, which can lead to significant resource waste. In this thesis, we target such resource wasting problems related to design and analysis of NoCs that are used in real-time systems. We propose a number of solutions to improve the schedulability of real-time traffic over wormhole-switched NoCs in order to further improve the resource utilization of the whole system. The solutions focus mainly on two aspects: (1) providing more accurate and efficient time analyses; (2) proposing more cost-effective scheduling methods.

The results presented in the thesis show a significant improvement both with regards to analysis and scheduling of real-time traffic in the context of two commonly used wormhole-switched NoC designs.