TY - GEN
T1 - Apec
T2 - 13th IEEE/ACM International Symposium on Networks-on-Chip, NOCS 2019
AU - Vonbun, Michael
AU - Schiechel, Adrian
AU - Vu Doan, Nguyen Anh
AU - Herkersdorf, Andreas
AU - Wild, Thomas
N1 - Publisher Copyright:
© 2019 Association for Computing Machinery.
PY - 2019/10/17
Y1 - 2019/10/17
N2 - Bufferless NoCs have been proposed as they come with a decreased silicon area footprint and a reduced power consumption, when compared to buffered NoCs. However, while known for their inherent simplicity, they suffer from early saturation and depend on additional measures to ensure reliable packet delivery, such as control protocols based on ACKs or NACKs. In this paper, we propose APEC, a novel concept for bufferless NoCs that allows to prioritize ACKs and NACKs over single payload flits of colliding packets by discarding the latter. Lightweight heuristic erasure codes are used to compensate for discarded payload flits. By trading off the erasure code overhead for packet retransmissions, a more efficient network operation is achieved. For ACK-based networks, APEC saturates at 2.1x and 2.875x higher generation rates than a conventional ACK-based bufferless NoC for packets between 5 and 17 flits. For NACK-based networks, APEC does not require concepts such as deflection routing or circuit-switched overlay NACK-networks, as prior work does. Therefore, it can simplify the network implementation compared to prior work while achieving similar performance.
AB - Bufferless NoCs have been proposed as they come with a decreased silicon area footprint and a reduced power consumption, when compared to buffered NoCs. However, while known for their inherent simplicity, they suffer from early saturation and depend on additional measures to ensure reliable packet delivery, such as control protocols based on ACKs or NACKs. In this paper, we propose APEC, a novel concept for bufferless NoCs that allows to prioritize ACKs and NACKs over single payload flits of colliding packets by discarding the latter. Lightweight heuristic erasure codes are used to compensate for discarded payload flits. By trading off the erasure code overhead for packet retransmissions, a more efficient network operation is achieved. For ACK-based networks, APEC saturates at 2.1x and 2.875x higher generation rates than a conventional ACK-based bufferless NoC for packets between 5 and 17 flits. For NACK-based networks, APEC does not require concepts such as deflection routing or circuit-switched overlay NACK-networks, as prior work does. Therefore, it can simplify the network implementation compared to prior work while achieving similar performance.
KW - Bufferless
KW - Erasure codes
KW - network-on-chip
UR - http://www.scopus.com/inward/record.url?scp=85076602398&partnerID=8YFLogxK
U2 - 10.1145/3313231.3352366
DO - 10.1145/3313231.3352366
M3 - Conference contribution
AN - SCOPUS:85076602398
T3 - Proceedings of the 13th IEEE/ACM International Symposium on Networks-on-Chip, NOCS 2019
BT - Proceedings of the 13th IEEE/ACM International Symposium on Networks-on-Chip, NOCS 2019
PB - Association for Computing Machinery
Y2 - 17 October 2019 through 18 October 2019
ER -