@phdthesis{Buechner2020, author = {B{\"u}chner, Steffen}, title = {Applying the stream-processing paradigm to ultra high-speed communication systems}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:co1-opus4-52462}, school = {BTU Cottbus - Senftenberg}, year = {2020}, abstract = {In the last 30 years, communication became one of the most important pillars of our civilization. Every day terabytes of information are moved wired and wireless between computers. In order to transport this amount of data, researchers and industry increase the data rates of the underlying communication networks with impressive speed. However, such ultra-high data rates are unavailable at the communication endpoints. One reason why ultra-high data rates are still not available for the communication endpoints is their inability to handle the protocol processing at this data rate. In order to enable communication endpoints to process high-volume data streams, the protocol processing has to be parallelized and optimized on all processing levels. However, parallelization and optimization are cumbersome tasks, which are further complicated as the protocol processing is traditionally carried out by the operating system. This thesis aims at circumventing these problems by moving the protocol processing into external processing hardware and interpreting communication protocols as stream processing problems. In order to achieve ultra-high data rates at the communication endpoints, a protocol stream processing design approach was developed and evaluated. The design process is separated into implementation, soft real-time analysis, parallelization, and mapping steps, which allow a scalable protocol implementation without paradigm changes. Furthermore, a data link protocol for 100 Gbit/s wireless was developed and implemented with the new stream processing design concept, in order to show its feasibility. The data link protocol is configurable for different communication conditions and easy to parallelize by providing different granularities of packets. The proposed design-process has shown to be suitable for uncovering bottlenecks and helping with debugging the individual stages of the protocol.}, subject = {Stream processing; Ultra high speed communication systems; Communication protocols; Wireless communication; End2End100; Stromverarbeitung; Ultra-Hoch-Geschwindigkeits-Kommunikationssysteme; Kommunikationsprotokolle; Drahtlose Kommunikation; Kommunikationsprotokoll; Protokollverarbeitung ; Hochgeschwindigkeitskommunikation; End2End100}, language = {en} } @phdthesis{Gypser2022, author = {Gypser, Philipp}, title = {Mechanisms for energy-efficient processor allocation and redistribution on manycore systems}, doi = {10.26127/BTUOpen-6385}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:co1-opus4-63853}, school = {BTU Cottbus - Senftenberg}, year = {2022}, abstract = {Multi- and manycore processors promise to combine high overall peak performance with moderate power consumption to meet the constantly growing demand for computational power under the energy constraints of today's CMOS technology. Future systems with manycore processors are expected to contain a huge amount of cores, which exceeds the number of processes that will run simultaneously. Consequently, processor time sharing approaches, that introduce significant overhead from regular context switches in common OS, will no longer be necessary. This work investigates mechanisms for scalable and energy-efficient spatial partitioning of multi- and manycore processor systems. In addition, it explores the implications of exclusive processor core allocation to user processes due to the absence of temporal multiplexing and offers approaches to ease the adaptation to the new programming model. The proposed mechanisms achieved fast thread allocation which motivates applications for dynamic thread allocation and benefits performance as well as energy efficiency. The efficiency control and resource revocation mechanisms detect and prevent wasteful and inefficient resource occupation from poorly optimized or malicious processes. In this way, the global efficiency of the system is optimized. The dynamic processing resource allocation and revocation handling has been integrated into a task parallel runtime system, to disburden the application programmer from manual implementation and to increase productivity.}, subject = {Manycore; Operating systems; Online profiling; Energy efficiency; Dynamic partitioning; Vielkernprozessor; Betriebssysteme; Profiling; Energie-Effizienz; Dynamische Partitionierung; Mehrkernprozessor; Betriebssystem; Partionierung; Energieeffizienz}, language = {en} }