Browsing by Subject "Network-on-chip"

Now showing 1 - 7 of 7

Open Access
Adaptive routing framework for network on chip architectures
(ACM, 2016-01) Mustafa, Naveed Ul; Öztürk, Özcan; Niar, S.
In this paper we suggest and demonstrate the idea of applying multiple routing algorithms during the execution of a real application mapped on a Network-on-Chip (NoC). Traffic pattern of a real application may change during its execution. As performance of an algorithm depends on the traffic pattern, using the same routing algorithm for the entire span of execution may be inefficient. We study the feasibility of this idea for applications such as SPARSE and MPEG-4 decoder, by applying different routing algorithms. By applying more than one routing algorithms, throughput improves up to 17.37% and 6.74% in the case of SPARSE and MPEG-4 decoder applications, respectively, as compared to the application of single routing algorithm. © 2016 ACM.
Open Access
Energy reduction in 3D NoCs through communication optimization
(Springer Wien, 2015) Ozturk, O.; Akturk I.; Kadayif I.; Tosun, S.
Network-on-Chip (NoC) architectures and three-dimensional (3D) integrated circuits have been introduced as attractive options for overcoming the barriers in interconnect scaling while increasing the number of cores. Combining these two approaches is expected to yield better performance and higher scalability. This paper explores the possibility of combining these two techniques in a heterogeneity aware fashion. Specifically, on a heterogeneous 3D NoC architecture, we explore how different types of processors can be optimally placed to minimize data access costs. Moreover, we select the optimal set of links with optimal voltage levels. The experimental results indicate significant savings in energy consumption across a wide range of values of our major simulation parameters.
Open Access
Fault-tolerant irregular topology design method for network-on-chips
(IEEE, 2014) Tosun, S.; Ajabshir V.B.; Mercanoglu O.; Öztürk, Özcan
As the technology sizes of integrated circuits (ICs) scale down rapidly, current transistor densities on chips dramatically increase. While nanometer feature sizes allow denser chip designs in each technology generation, fabricated ICs become more susceptible to wear-outs, causing operation failure. Even a single link failure within an on-chip fabric can halt communication between application blocks, which makes the entire chip useless. In this study, we aim to make faulty chips designed with Network-on-Chip (NoC) communication usable. Specifically, we present a fault-tolerant irregular topology generation method for application specific NoC designs. Designed NoC topology allows a different routing path if there is a link failure on the default routing. We compare fault-tolerant topologies with regular fault-tolerant ring topologies, and non-fault-tolerant application specific irregular topologies on energy consumption, performance, and area using multimedia benchmarks and custom-generated graphs. © 2014 IEEE.
Open Access
FPGA implementation of a fault-tolerant application-specific NoC design
(IEEE, 2016-04) Yeşil, Şerif; Tosun, S.; Öztürk, Özcan
Today's integrated circuits are more susceptible to permanent link failures than before as a result of diminishing technology sizes. Even a single link failure can make an entire chip useless. Single link failure problem is fatal to application-specific Network-on-Chip (NoC) designs as well if they cannot tolerate such failures. One solution to this problem can be having alternative routing options on the network for each communicating pair. In this study, we present an FPGA implementation of such a method for application-specific NoCs. This method adds additional network resources to the non-fault-tolerant design in an attempt to make it fault-tolerant. We show the effects of the presented fault-tolerant method on an FPGA implementation of Mp3 encoder based on energy consumption and area increase against non-fault-tolerant case. © 2016 IEEE.
Open Access
Optimization-based power and thermal management for dark silicon aware 3D chip multiprocessors using heterogeneous cache hierarchy
(Elsevier BV, 2017) Asad, A.; Ozturk, O.; Fathy, M.; Jahed-Motlagh, M. R.
Management of a problem recently known as “dark silicon” is a new challenge in multicore designs. Prior innovative studies have addressed the dark silicon problem in the fields of power-efficient core design. However, addressing dark silicon challenges in uncore component designs such as cache hierarchy, on-chip interconnect etc. that consume significant portion of the on-chip power consumption is largely unexplored. In this paper, for the first time, we propose an integrated approach which considers the impact of power consumption of core and uncore components simultaneously to improve multi/many-core performance in the dark silicon era. The proposed approach dynamically (1) predicts the changing program behavior on each core; (2) re-determines frequency/voltage, cache capacity and technology in each level of the cache hierarchy based on the program's scalability in order to satisfy the power and temperature constraints. In the proposed architecture, for future chip-multiprocessors (CMPs), we exploit emerging technologies such as non-volatile memories (NVMs) and 3D techniques to combat dark silicon. Also, for the first time, we propose a detailed power model which is useful for future dark silicon CMPs power modeling. Experimental results on SPEC 2000/2006 benchmarks show that the proposed method improves throughput by about 54.3% and energy-delay product by about 61% on average, respectively, in comparison with the conventional CMP architecture with homogenous cache system. (A preliminary short version of this work was presented in the 18th Euromicro Conference on Digital System Design (DSD), 2015.) © 2017 Elsevier B.V.
Open Access
Temperature-aware core mapping for heterogeneous 3D NoC design through constraint programming
(Institute of Electrical and Electronics Engineers, 2020) Demiriz, A.; Ahangari, Hamzeh; Öztürk, Özcan
In the context of Network-on-Chip (NoC) based Chip Multiprocessor (CMP) design, core mapping for application specific systems is a challenging problem. In such designs, various decisions have to be made that affect performance and power consumption. Moreover, in emerging 3D NoC systems, by intensification of cooling issues, temperature constraints on hot-spots are added, and problem becomes more complicated. In this paper, an earlier Constraint Programming (CP) methodology for heterogeneous 2D NoC design is extended to 3D model, while critical temperature constraints are accounted. In a single-stage, our approach can choose core types from a set of low, medium and high power, and assign them to appropriate places on the mesh which minimizes the overall computation time and communication cost while satisfying the temperature constraints. To achieve our objective, in addition to cores placement problem, tasks should also be scheduled on corresponding cores with matching performance levels to minimize the overall completion time (makespan). Experimental results show that task completion times are more dependent on the mesh structure for our benchmark data. 3D mesh structures may yield shorter task completion times, without compromising thermal constraints. On the other hand, restricting the peak temperature naturally requires the usage of low-performance computing elements which inherently may delay the processing time.
Open Access
Voltage island based heterogeneous NoC design through constraint programming
(Pergamon Press, 2014) Demiriz, A.; Bagherzadeh, N.; Ozturk, O.
This paper discusses heterogeneous Network-on-Chip (NoC) design from a Constraint Programming (CP) perspective and extends the formulation to solving Voltage-Frequency Island (VFI) problem. In general, VFI is a superior design alternative in terms of thermal constraints, power consumption as well as performance considerations. Given a Communication Task Graph (CTG) and subsequent task assignments for cores, cores are allocated to the best possible places on the chip in the first stage to minimize the overall communication cost among cores. We then solve the application scheduling problem to determine the optimum core types from a list of technological alternatives and to minimize the makespan. Moreover, an elegant CP model is proposed to solve VFI problem by mapping and grouping cores at the same time with scheduling the computation tasks as a limited capacity resource allocation model. The paper reports results based on real benchmark datasets from the literature.