Title :
Analysis of worst-case delay bounds for best-effort communication in wormhole networks on chip
Author :
Qian, Yue ; Lu, Zhonghai ; Dou, Wenhua
Author_Institution :
Sch. of Comput. Sci., Nat. Univ. of Defense Technol., Changsha
Abstract :
In packet-switched network-on-chip, computing worst-case delay bounds is crucial for designing predictable and cost-effective communication systems but yet an intractable problem due to complicated resource sharing scenarios. For wormhole networks with credit-based flow control, the existence of cyclic dependency between flit delivery and credit generation further complicates the problem. Based on network calculus, we propose a technique for analyzing communication delay bounds for individual flows in wormhole networks. We first propose router service analysis models for flow control, link and buffer sharing. Based on these analysis models, we obtain a buffering-sharing analysis network, which is open-ended and captures both flow control and link sharing. Furthermore, we compute equivalent service curves for individual flows using the network contention tree model in the buffer-sharing analysis network, and then derive their delay bounds. Our experimental results verify that the theoretical bounds are correct and tight.
Keywords :
buffer circuits; circuit theory; multiprocessor interconnection networks; network routing; network-on-chip; quality of service; best-effort communication; buffering-sharing analysis network; credit-based flow control; link; network contention tree model; packet-switched network-on-chip; router service analysis; wormhole networks; worst-case delay bounds; Calculus; Communication system control; Communication system traffic control; Communication systems; Computer networks; Delay; Network-on-a-chip; Resource management; Telecommunication traffic; Traffic control;
Conference_Titel :
Networks-on-Chip, 2009. NoCS 2009. 3rd ACM/IEEE International Symposium on
Conference_Location :
San Diego, CA
Print_ISBN :
978-1-4244-4142-6
Electronic_ISBN :
978-1-4244-4143-3
DOI :
10.1109/NOCS.2009.5071444