Details of a Researcher - Kondo, Masaaki

Kondo, Masaaki

写真a

Affiliation: Faculty of Science and Technology, Department of Information and Computer Science （Yagami）

Position: Professor

Related Websites

https://sites.google.com/view/kondo-lab

Page Top ▲

Research Areas 【 Display / hide 】

Informatics / Computer system

Page Top ▲

Research Keywords 【 Display / hide 】

Computer Architecture
High Performance Computing
Quantum Computing

Page Top ▲

Papers 【 Display / hide 】

Evaluation of Performance and Power Consumption on Supercomputer Fugaku Using SPEC HPC Benchmarks

Kodama Y., Kondo M., Sato M.

IEICE Transactions on Electronics （IEICE Transactions on Electronics) E106.C （ 6 ） 303 - 311 2023.06

ISSN 09168524

　View Summary

The supercomputer, “Fugaku”, which ranked number one in multiple supercomputing lists, including the Top500 in June 2020, has various power control features, such as (1) an eco mode that utilizes only one of two floating-point pipelines while decreasing the power supply to the chip; (2) a boost mode that increases clock frequency; and (3) a core retention feature that turns unused cores to the low-power state. By orchestrating these power-performance features while considering the characteristics of running applications, we can potentially gain even better system-level energy efficiency. In this paper, we report on the performance and power consumption of Fugaku using SPEC HPC benchmarks. Consequently, we confirmed that it is possible to reduce the energy by about 17% while improving the performance by about 2% from the normal mode by combining boost mode and eco mode.
- Access to Document (DOI)
An Interactive and Reductive Graph Processing Library for Edge Computing in Smart Society

Zhou J., Kondo M.

IEICE Transactions on Information and Systems （IEICE Transactions on Information and Systems) E106D （ 3 ） 319 - 327 2023.03

ISSN 09168532

　View Summary

Due to the limitations of cloud computing on latency, bandwidth and data confidentiality, edge computing has emerged as a novel location-aware paradigm to provide them with more processing capacity to improve the computing performance and quality of service (QoS) in several typical domains of human activity in smart society, such as social networks, medical diagnosis, telecommunications, recommendation systems, internal threat detection, transports, Internet of Things (IoT), etc. These application domains often handle a vast collection of entities with various relationships, which can be naturally represented by the graph data structure. Graph processing is a powerful tool to model and optimize complex problems in which the graph-based data is involved. In view of the relatively insufficient resource provisioning of the portable terminals, in this paper, for the first time to our knowledge, we propose an interactive and reductive graph processing library (GPL) for edge computing in smart society at low overhead. Experimental evaluation is conducted to indicate that the proposed GPL is more user-friendly and highly competitive compared with other established systems, such as igraph, NetworKit and NetworkX, based on different graph datasets over a variety of popular algorithms.
- Access to Document (DOI)
Exploiting Data Parallelism in Graph-Based Simultaneous Localization and Mapping: A Case Study with GPU Accelerations

Zheng J., He Y., Kondo M.

ACM International Conference Proceeding Series （ACM International Conference Proceeding Series) 126 - 139 2023.02

　View Summary

Graph-based simultaneous localization and mapping (G-SLAM) is an intuitive SLAM implementation where graphs are used to represent poses, landmarks and sensor measurements when a mobile robot builds a map of the environment and locates itself in it. Being a very important application employed in many realistic scenarios, estimating the whole environment and all trajectories through solving graph problems for SLAM can incur a large amount of computation and consume a significant amount of energy. For the purpose of improving both performance and energy efficiency, we have unveiled the critical path of the G-SLAM algorithm in this paper and implemented a GPU-based solution to aid it. Furthermore, we have attempted to offload performance-critical components (such as matrix inversions when updating the trajectory) in the G-SLAM process into GPUs through CUDA to exploit data parallelism. With our solution, we observe a speed-up of up to 19.7x and an energy saving of up to 83.7% over a modern workstation class x86 CPU; while on a platform dedicated for edge computing (NVIDIA Jetson Nano), we achieve a speed-up of up to 2.5x and an energy saving of up to 6.4% with its integrated GPU, respectively.
- Access to Document (DOI)
A Scalable Body Bias Optimization Method Toward Low-Power CGRAs

Kojima T., Okuhara H., Kondo M., Amano H.

IEEE Micro （IEEE Micro) 43 （ 1 ） 49 - 57 2023.01

ISSN 02721732

　View Summary

Body biasing is one of the critical techniques to realize more energy-efficient computing with reconfigurable devices, such as coarse-grained reconfigurable architectures. Its benefit depends on the control granularity, whereas fine-grained control makes it challenging to find the best body bias voltage for each domain due to the complexity of the optimization problem. This work reformulates the optimization problem and introduces continuous relaxation to solve it faster than previous work based on an integer linear program. Experimental result shows the proposed method can solve the problem within 0.5 s for all benchmarks in any conditions. For a middle-class problem, up to 5.65- speedup and a geometric mean of 2.06 - speedup are demonstrated compared to the previous method with negligible loss of accuracy. Besides, we explore finer body bias control considering the power- and area-overhead of an on-chip body bias generator and suggest the most reasonable design saves 66% of energy consumption.
- Access to Document (DOI)
An Edge-Cloud Collaboration Framework for Graph Processing in Smart Society

Zhou J., Kondo M.

IEEE Transactions on Emerging Topics in Computing （IEEE Transactions on Emerging Topics in Computing) 2023

　View Summary

Due to the limitations of cloud computing on latency, bandwidth and data confidentiality, edge computing has emerged as a novel location-aware way to provide the capacity-constrained portable terminals with more processing capacity to improve the computing performance and quality of service (QoS) in several typical domains of the human activity in smart society, such as social networks, medical diagnosis, telecommunications, recommendation systems, internal threat detection, transportation, Internet of Things (IoT), etc. These application domains often manage a vast collection of entities with various relationships, which can be naturally represented by the graph data structure. Graph processing is a powerful tool to model and optimize complex problems where graph-based data is involved. In consideration of the relatively insufficient resource provisioning of the edge devices, in this paper, for the first time to our knowledge, we propose a reliable edge-cloud collaboration framework that facilitates the graph primitives based on a lightweight interactive graph processing library (GPL), especially for shortest path search (SPS) operations as the demonstrative example. Two types of different practical cases are also presented to show the typical application scenarios of our graph processing strategy. Experimental evaluations indicate that the acceleration rate of performance can reach 6.87x via graph reduction, and less than 3% and 20% extra latency is required for much better user experiences for navigation and pandemic control, respectively, while the online security measures merely consume about 1% extra time of the overall data transmission. Our framework can efficiently execute the applications with considering of user-friendliness, low-latency response, interactions among edge devices, collaboration between edge and cloud, and privacy protection at an acceptable overhead.
- Access to Document (DOI)