{"id":4559,"date":"2018-06-14T02:38:59","date_gmt":"2018-06-14T02:38:59","guid":{"rendered":"http:\/\/filewood.snu.ac.kr\/wordpress\/?page_id=4559"},"modified":"2025-06-27T12:29:10","modified_gmt":"2025-06-27T03:29:10","slug":"research_new","status":"publish","type":"page","link":"https:\/\/redwood.snu.ac.kr\/wordpress\/index.php\/research_new\/","title":{"rendered":"Research"},"content":{"rendered":"<p><!---------------Research Thrust-------------------------------><\/p>\n<p><center><img decoding=\"async\" src=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2025\/06\/header-img-5.png\" alt=\"Research Thrust\" name=\"\" \/><\/center><!-------------------Research Thrust END-------------------------------><br \/>\n<!----------------------Topic 1---------------------><\/p>\n<div style=\"text-align: justify; font-family: arial; font-size: 18pt; line-height: 100%;\"><div class=\"su-spoiler su-spoiler-style-simple su-spoiler-icon-plus\" data-scroll-offset=\"0\" data-anchor-in-url=\"no\"><div class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>1. Software-Defined Vehicles and Cloud Native Computing<\/div><div class=\"su-spoiler-content su-u-clearfix su-u-trim\">\n<!------><\/p>\n<table border=\"0\" width=\"100%\" cellspacing=\"0\" cellpadding=\"0\"><!--A----><\/p>\n<tbody>\n<tr>\n<td colspan=\"2\">\n<div style=\"text-align: justify; font-family: arial; font-size: 11pt; line-height: 100%;\"><b>Developing a service-oriented software platform for software-defined vehicles based on SOAFEE and SOME\/IP <\/b><\/div>\n<\/td>\n<\/tr>\n<tr>\n<td valign=\"top\" width=\"20%\">\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\"><img decoding=\"async\" src=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2023\/09\/1-1.png\" alt=\"\" width=\"95%\" height=\"150\" name=\"\" \/><\/div>\n<p><!--\uc5f0\uad6c\uc774\ubbf8\uc9c0--><\/td>\n<td valign=\"top\">\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\">Software-defined vehicles (SDVs) have emerged as a core enabling technology for future mobility. Their ultimate success depends on the implementation of Service-Oriented Architecture (SOA). SOA is a software development\/operation methodology that separates various functions of a system into service units, connects them on a network, and builds and operates them as a system. SOA began in the enterprise computing field, and its usefulness has been proven in terms of system agility, interoperability between components and systems, deployment flexibility, and reusability.<\/div>\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\">Although SOA is essential for SDVs, enterprise computing SOA technology cannot be directly applied to vehicular systems since it does not consider the functional safety of the underlying system. A software platform for SDVs must guarantee the verified performance of services along with the dynamic distribution of services.<\/div>\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\">The AUTOSAR Adaptive Platform (AP) has been proposed in the automotive industry, as an industry-strength SOA platform for SDVs. While AP is currently receiving a lot of attention in the automotive industry, it has functional and non-functional limitations that have not yet been resolved as an SDV runtime platform. Additionally, AP was presented as an independent standard within the automotive industry, and thus it has shortcomings in terms of openness for cloud native computing. Consequently, open source-based software platforms for SDVs are actively underway. The related projects attempt to define architecture standards in a code-first manner based on open sources such as Kubernetes and Docker.<\/div>\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\">At RTOSLab of SNU, to build the foundation for an open, cloud native SDV runtime platform, we develop a SOAFEE-based PoC (proof-of-concept) system using Kubernetes and Docker. To this end, we integrate SOME\/IP into SOAFEE and implement it on a hardware testbed that models a centralized zonal E\/E architecture.<\/div>\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\"><div class=\"su-list\" style=\"margin-left:0px\">\n<ul>\n<li><i class=\"sui sui-folder-o\" style=\"color:#333\"><\/i> <b>Publications<\/b><\/li>\n<li type=\"\">Namcheol Lee, Woobean Seo, Seongsoo Hong, and Saehwa Kim, <a href=\"https:\/\/papers.ssrn.com\/sol3\/papers.cfm?abstract_id=5293354\" target=\"_blank\" rel=\"noopener\">&#8220;A Protocol-Agnostic and Automated Approach to Bi-directional Inter-Domain Communication in Software-Defined Vehicles<\/a>,&#8221; Manuscript submitted for international journal publication, June 2025<\/li>\n<li type=\"\">Namcheol Lee, Seongsoo Hong, and Saehwa Kim, <a href=\"https:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2024\/07\/ICDCS-2024-MCS-SDV.pdf\" target=\"_blank\" rel=\"noopener\">&#8220;Dynamic Mapping of Mixed-Criticality Applications onto a Mixed-Criticality Runtime System with Probabilistic Guarantees<\/a>,&#8221; The 2024 IEEE 44th International Conference on Distributed Computing Systems (ICDCS 2024), pp. 1466-1467, July 2024. (Won Best Ph.D Student Symposium Paper Award at ICDCS 2024)<\/li>\n<\/ul>\n<ul>\n<li><i class=\"sui sui-folder-o\" style=\"color:#333\"><\/i> <b>Projects<\/b><\/li>\n<li type=\"\">\uac1c\ubc29\ud615 \uc790\uc728\uc8fc\ud589 \uc751\uc6a9 SW \uac1c\ubc1c\uc744 \uc704\ud55c \uc0b0\uc5c5\ud45c\uc900 HW \ud50c\ub7ab\ud3fc \uae30\uc220\uac1c\ubc1c, 2024-2028<\/li>\n<li type=\"\">\uad6d\uc0b0 SoC \uae30\ubc18 \ub3c4\uba54\uc778 \ud1b5\ud569\ud615 \uc911\uc559\ucef4\ud4e8\ud305 \uc2dc\uc2a4\ud15c \uac1c\ubc1c \ubc0f \ucc28\ub7c9\uc6a9 SW \uc0b0\uc5c5 \uc0dd\ud0dc\uacc4 \uad6c\ucd95 (\uc81c\uc548 \uc911)<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<\/td>\n<\/tr>\n<tr>\n<td colspan=\"2\"><!--\uacf5\ub780--><\/td>\n<\/tr>\n<tr>\n<td colspan=\"2\">\n<div style=\"text-align: justify; font-family: arial; font-size: 11pt; line-height: 100%;\"><b>Enhancing SOME\/IP for real-time communications<\/b><\/div>\n<\/td>\n<\/tr>\n<tr>\n<td valign=\"top\" width=\"20%\">\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\"><img decoding=\"async\" src=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2023\/09\/1-2.png\" alt=\"\" width=\"95%\" height=\"150\" name=\"\" \/><\/div>\n<p><!--\uc5f0\uad6c\uc774\ubbf8\uc9c0--><\/td>\n<td valign=\"top\">\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\">SOME\/IP is communication middleware that supports service-oriented communications and is one of the core technologies of the software platform for SDVs. But SOME\/IP has four inherent limitations that can restrict its use in SDVs: (1) bounded message transfer latency, (2) limited throughput for huge data transfers, (3) unbounded boot time of a service instance, and (4) unbounded service discovery time.<\/div>\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\">We conduct research to quantitatively measure these problems in SOME\/IP, locate bottleneck points within the protocol stack, and systematically improve them.<\/div>\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\"><div class=\"su-list\" style=\"margin-left:0px\">\n<ul>\n<li><i class=\"sui sui-folder-o\" style=\"color:#333\"><\/i> <b>Publications<\/b><\/li>\n<li type=\"\">Namcheol Lee, Woobean Seo, Seongsoo Hong, and Saehwa Kim, <a href=\"https:\/\/papers.ssrn.com\/sol3\/papers.cfm?abstract_id=5293354\" target=\"_blank\" rel=\"noopener\">&#8220;A Protocol-Agnostic and Automated Approach to Bi-directional Inter-Domain Communication in Software-Defined Vehicles<\/a>,&#8221; Manuscript submitted for international journal publication, June 2025<\/li>\n<\/ul>\n<ul>\n<li><i class=\"sui sui-folder-o\" style=\"color:#333\"><\/i> <b>Projects<\/b><\/li>\n<li type=\"\">\uac1c\ubc29\ud615 \uc790\uc728\uc8fc\ud589 \uc751\uc6a9 SW \uac1c\ubc1c\uc744 \uc704\ud55c \uc0b0\uc5c5\ud45c\uc900 HW \ud50c\ub7ab\ud3fc \uae30\uc220\uac1c\ubc1c, 2024-2028<\/li>\n<li type=\"\">SDV\uc6a9 \uc804\uc790 \uc544\ud0a4\ud14d\ucc98\ub97c \uc704\ud55c \ucc28\ub7c9\uc6a9 \ub3c4\uba54\uc778\uc774 \uc801\uc6a9\ub41c \ud1b5\ud569\uc81c\uc5b4\uae30 \uae30\uc220\uac1c\ubc1c \ubc0f \uc2e4\uc99d, 2023~2026<\/li>\n<li type=\"\">\uad6d\uc0b0 SoC \uae30\ubc18 \ub3c4\uba54\uc778 \ud1b5\ud569\ud615 \uc911\uc559\ucef4\ud4e8\ud305 \uc2dc\uc2a4\ud15c \uac1c\ubc1c \ubc0f \ucc28\ub7c9\uc6a9 SW \uc0b0\uc5c5 \uc0dd\ud0dc\uacc4 \uad6c\ucd95 (\uc81c\uc548 \uc911)<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<\/td>\n<\/tr>\n<tr>\n<td colspan=\"2\"><!--\uacf5\ub780--><\/td>\n<\/tr>\n<tr>\n<td colspan=\"2\">\n<div style=\"text-align: justify; font-family: arial; font-size: 11pt; line-height: 100%;\"><b>System software supporting on-device AI<\/b><\/div>\n<\/td>\n<\/tr>\n<tr>\n<td valign=\"top\" width=\"20%\">\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\"><img decoding=\"async\" src=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2025\/01\/1-3.png\" alt=\"\" width=\"95%\" height=\"150\" name=\"\" \/><\/div>\n<p><!--\uc5f0\uad6c\uc774\ubbf8\uc9c0--><\/td>\n<td valign=\"top\">\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\"><!--\ub0b4\uc6a9\ucd94\uac00--><\/div>\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\"><!--\ub0b4\uc6a9\ucd94\uac00--><\/div>\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\"><div class=\"su-list\" style=\"margin-left:0px\">\n<ul>\n<li><i class=\"sui sui-folder-o\" style=\"color:#333\"><\/i> <b>Publications<\/b><\/li>\n<li type=\"\">Philkyue Shin, Myungsun Kim, Seongsoo Hong, <a href=\"https:\/\/doi.org\/10.1016\/j.sysarc.2025.103508\" target=\"_blank\" rel=\"noopener\">&#8220;Inference Framework Supporting Parallel Execution across Heterogeneous Accelerators<\/a>,&#8221; Journal of Systems Architecture, June 2025<\/li>\n<li type=\"\">Woobean Seo, Saehwa Kim, and Seongsoo Hong, <a href=\"https:\/\/doi.org\/10.1016\/j.sysarc.2025.103462\" target=\"_blank\" rel=\"noopener\">&#8220;DNNPipe: Dynamic Programming-based Optimal DNN Partitioning for Pipelined Inference on IoT Networks<\/a>,&#8221;Journal of Systems Architecture, Volume 166, 10346, May 2025<\/li>\n<li type=\"\">Woobean Seo, Saehwa Kim, and Seongsoo Hong, <a href=\"https:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2024\/07\/ICDCS-2024-DNNPipe.pdf\">&#8220;Partitioning Deep Neural Networks for Optimally Pipelined Inference on Heterogeneous IoT Devices with Low Latency Networks<\/a>,&#8221; The 2024 IEEE 44th International Conference on Distributed Computing Systems (ICDCS 2024), 1470-1471, July 2024<\/li>\n<\/ul>\n<p><!--\ud504\ub85c\uc81d\ud2b8 \ucd94\uac00\n\n\n<ul>\n \t\n\n<li><i class=\"sui sui-folder-o\" style=\"color:#333\"><\/i> <b>Projects<\/b><\/li>\n\n\n \t\n\n<li type=\"\">\uac1c\ubc29\ud615 \uc790\uc728\uc8fc\ud589 \uc751\uc6a9 SW \uac1c\ubc1c\uc744 \uc704\ud55c \uc0b0\uc5c5\ud45c\uc900 HW \ud50c\ub7ab\ud3fc \uae30\uc220\uac1c\ubc1c, 2024-2028<\/li>\n\n\n \t\n\n<li type=\"\">SDV\uc6a9 \uc804\uc790 \uc544\ud0a4\ud14d\ucc98\ub97c \uc704\ud55c \ucc28\ub7c9\uc6a9 \ub3c4\uba54\uc778\uc774 \uc801\uc6a9\ub41c \ud1b5\ud569\uc81c\uc5b4\uae30 \uae30\uc220\uac1c\ubc1c \ubc0f \uc2e4\uc99d, 2023~2026<\/li>\n\n\n \t\n\n<li type=\"\">SDV\ub97c \uc704\ud55c Kubernetes\/Docker, SOME\/IP \uae30\ubc18\uc758 \ucc28\ub7c9 \uc6a9 \ub3d9\uc801 \uc11c\ube44\uc2a4 \ud50c\ub7ab\ud3fc\uc758 PoC \uad6c\ud604\uacfc SOME\/IP \ucd5c\uc801\ud654 (\uc81c\uc548 \uc911)<\/li>\n\n\n<\/ul>\n\n\n--><\/div>\n<\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div><\/div>\n<\/div>\n<p><!----------------------Topic 1 End---------------------><!----------------------Topic 2---------------------><\/p>\n<div style=\"text-align: justify; font-family: arial; font-size: 18pt; line-height: 100%;\"><div class=\"su-spoiler su-spoiler-style-simple su-spoiler-icon-plus\" data-scroll-offset=\"0\" data-anchor-in-url=\"no\"><div class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>2. Kernel Techniques for Active Resource Management<\/div><div class=\"su-spoiler-content su-u-clearfix su-u-trim\">\n<!------><\/p>\n<table border=\"0\" width=\"100%\" cellspacing=\"0\" cellpadding=\"0\"><!--A----><\/p>\n<tbody>\n<tr>\n<td colspan=\"2\">\n<div style=\"text-align: justify; font-family: arial; font-size: 11pt; line-height: 100%;\"><b>Reducing memory interference latency of safety-critical applications via memory request throttling and Linux cgroup<\/b><!--| <a href=\"http:\/\/redwood.snu.ac.kr\/wordpress\/index.php\/project_1-a\/\" target=\"_blank\" rel=\"noopener\">Project page<\/a>--><\/div>\n<\/td>\n<\/tr>\n<tr>\n<td valign=\"top\" width=\"20%\">\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\"><img decoding=\"async\" src=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2018\/06\/1-A.-Reducing-memory-interference-latency-of-safety-critical-application....png\" alt=\"\" width=\"95%\" height=\"150\" name=\"\" \/><\/div>\n<\/td>\n<td valign=\"top\">\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\">With the advent of high-performance multicore processors that operate under a limited power budget, dedicated low-end microprocessors with different levels of criticality are rapidly consolidated into a mixed-criticality system. One of the major challenges in designing such a mixed-criticality system is to tightly control the amount of resource contention for a critical application by effectively limiting its performance interference incurred due to sharing resources with non-critical tasks. We propose application-aware dynamic memory request throttling to reduce the memory interference latency of a critical application in a dual criticality system. Our approach carefully differentiates critical task instances from normal task instances and groups them into the critical and normal cgroup, respectively. It then predicts the occurrence of excessive memory contention under critical task execution and then throttles memory requests generated by the normal cgroup via the CPUFreq governor when necessary.<div class=\"su-list\" style=\"margin-left:0px\">\n<ul>\n<li><i class=\"sui sui-folder-o\" style=\"color:#333\"><\/i> <b>Publications<\/b><\/li>\n<li type=\"\">Philkyue Shin, Dahun Kim and Seongsoo Hong, <a href=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2023\/05\/23-04-28-mSchedutil.pdf\" target=\"_blank\" rel=\"noopener\">&#8220;Memory-Aware DVFS Governing Policy for Improved Energy-Saving in the Linux Kernel<\/a>,&#8221; The 29th IEEE International Conference on Embedded and Real-Time Computing Systems and Applications (RTCSA 2023), pp. 57-66, August 2023<\/li>\n<li type=\"\">Jungho Kim, Philkyue Shin, Myungsun Kim and Seongsoo Hong, <a href=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2020\/03\/mCFS_Access_Final.pdf\" target=\"_blank\" rel=\"noopener\">&#8220;Memory-Aware Fair-Share Scheduling for Improved Performance Isolation in the Linux Kernel<\/a>,&#8221; IEEE Access, vol. 8, pp. 98874-98886, Jun 2020<\/li>\n<li type=\"\">Jungho Kim, Philkyue Shin, Soonhyun Noh, Daesik Ham and Seongsoo Hong, <a href=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2018\/08\/18-07-30-SOCC_Memory-Request-Throttling_final.pdf\">&#8220;Reducing Memory Interference Latency of Safety-Critical Applications via Memory Request Throttling and Linux cgroup,&#8221;<\/a> The proceedings of 31st IEEE International System-on-Chip Conference (SOCC 2018), pp. 215-220, Sep 2018<\/li>\n<\/ul>\n<ul>\n<li><i class=\"sui sui-folder-o\" style=\"color:#333\"><\/i> <b>Projects<\/b><\/li>\n<li type=\"\">Multicore NPU\uc758 \uc18c\ube44\uc5d0\ub108\uc9c0 \uc808\uac10\uc744 \uc704\ud55c SW \uae30\uc220 \uac1c\ubc1c, 2020~2025<\/li>\n<li type=\"\">CPU-GPU Shared Virtual Memory\ub97c \uc9c0\uc6d0\ud558\uae30 \uc704\ud55c Memory Management \uae30\uc220 \uac1c\ubc1c, 2018~2020<\/li>\n<li type=\"\">Linux kernel optimization for high-performance real-time computing, 2017<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div><\/div>\n<\/div>\n<p><!----------------------Topic 2 End---------------------><!----------------------Topic 3---------------------><\/p>\n<div style=\"text-align: justify; font-family: arial; font-size: 18pt; line-height: 100%;\"><div class=\"su-spoiler su-spoiler-style-simple su-spoiler-icon-plus\" data-scroll-offset=\"0\" data-anchor-in-url=\"no\"><div class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>3. Linux Kernel Scheduling for Symmetric\/Asymmetric Multicore Systems<\/div><div class=\"su-spoiler-content su-u-clearfix su-u-trim\"><!--A-end----><!--B-end----><\/p>\n<table border=\"0\" width=\"100%\" cellspacing=\"0\" cellpadding=\"0\">\n<tbody>\n<tr><!--A----><\/p>\n<td colspan=\"2\">\n<div style=\"text-align: justify; font-family: arial; font-size: 11pt; line-height: 100%;\"><b>Providing fair-share scheduling in single-ISA asymmetric multicore architecture via scaled virtual runtime and load redistribution<\/b><!-- | <a href=\"http:\/\/redwood.snu.ac.kr\" target=\"_blank\" rel=\"noopener\">Project page<\/a>--><\/div>\n<\/td>\n<\/tr>\n<tr>\n<td valign=\"top\" width=\"20%\">\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\"><img decoding=\"async\" src=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2018\/06\/2-B.-Providing-fair-share-scheduling-on-symmetric-multicore-computing-systems-via-progress-balancing.png\" alt=\"\" width=\"95%\" height=\"150\" name=\"\" \/><\/div>\n<\/td>\n<td valign=\"top\">\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\">Performance-asymmetric multicore processors have been increasingly adopted in embedded systems due to their architectural benefits in improved performance and power savings. While fair-share scheduling is a crucial kernel service for such applications, it is still at an early stage with respect to performance-asymmetric multicore architecture. We first propose a new fair-share scheduler by adopting the notion of scaled CPU time that reflects the performance asymmetry between different types of cores. Using the scaled CPU time, we revise the virtual runtime of the completely fair scheduler (CFS) of the Linux kernel, and extend it into the scaled virtual runtime (SVR). In addition, we propose an SVR balancing algorithm that bounds the maximum SVR difference of tasks running on the same core types. The SVR balancing algorithm periodically partitions the tasks in the system into task groups and allocates them to the cores in such a way that tasks with smaller SVR receive larger SVR increments and thus proceed more quickly.<div class=\"su-list\" style=\"margin-left:0px\">\n<ul>\n<li><i class=\"sui sui-folder-o\" style=\"color:#333\"><\/i> <b>Publications<\/b><\/li>\n<li type=\"\">Jungho Kim, Philkyue Shin, Myungsun Kim and Seongsoo Hong, <a href=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2020\/03\/mCFS_Access_Final.pdf\" target=\"_blank\" rel=\"noopener\">&#8220;Memory-Aware Fair-Share Scheduling for Improved Performance Isolation in the Linux Kernel<\/a>,&#8221; IEEE Access, vol. 8, pp. 98874-98886, Jun 2020<\/li>\n<li type=\"\">Myungsun Kim, Soonhyun Noh, Jinhwa Hyeon and Seongsoo Hong, <a href=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2016\/06\/JPDC_2018.pdf\">&#8220;Fair-share Scheduling in Single-ISA Asymmetric Multicore Architecture via Scaled Virtual Runtime and Load Redistribution,&#8221; <\/a>Journal of Parallel and Distributed Computing, vol. 111, pp. 174-186, Jan 2018<\/li>\n<li type=\"\">Myungsun Kim, Soonhyun Noh, Sungju Huh and Seongsoo Hong, <a href=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2015\/10\/15-RTCSA.pdf\">&#8220;Fair-share Scheduling for Performance-asymmetric Multicore Architecture via Scaled Virtual Runtime,&#8221;<\/a> 2015 IEEE 21st International Conference on Embedded and Real-Time Computing Systems and Applications, pp. 60-69, Aug 2015<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<\/td>\n<\/tr>\n<tr>\n<td colspan=\"2\"><!--\uacf5\ub780--><\/td>\n<\/tr>\n<tr><!--B-----><\/p>\n<td colspan=\"2\">\n<div style=\"text-align: justify; font-family: arial; font-size: 11pt; line-height: 100%;\"><b>Providing fair-share scheduling on symmetric multicore computing systems via progress balancing<\/b><!-- | <a href=\"http:\/\/redwood.snu.ac.kr\/wordpress\/index.php\/project_2-a\" target=\"_blank\" rel=\"noopener\">Project page<\/a>--><\/div>\n<\/td>\n<\/tr>\n<tr>\n<td valign=\"top\" width=\"20%\">\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\"><!--<img decoding=\"async\" src=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2018\/06\/2-A.-Providing-fair-share-scheduling-on-symmetric-multicore-computing-systems-via-progress-balancing.png\" alt=\"\" width=\"95%\" height=\"150\" name=\"\" \/>--><\/div>\n<\/td>\n<td valign=\"top\">\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\">Performance isolation in a scalable multicore system is often attempted through periodic load balancing paired with per-core fair-share scheduling. Unfortunately, load balancing cannot guarantee the desired level of multicore fairness since it may produce unbounded differences in the progress of tasks. In reality, the balancing of load across cores is only indirectly related to multicore fairness. To address this limitation and ultimately achieve multicore fairness, we propose a new task migration policy we name progress balancing, and present an algorithm for its realization. Progress balancing periodically distributes tasks among cores to directly balance the progress of tasks by bounding their virtual runtime differences. In doing so, it partitions runnable tasks into task groups and allocates them onto cores such that tasks with larger virtual runtimes run on a core with a larger load and thus proceed more slowly.<div class=\"su-list\" style=\"margin-left:0px\">\n<ul>\n<li><i class=\"sui sui-folder-o\" style=\"color:#333\"><\/i> <b>Publications<\/b><\/li>\n<li type=\"\">Sungju Huh and Seongsoo Hong, <a href=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2016\/06\/JPDC_2018.pdf\">&#8220;Providing Fair-share Scheduling on Multicore Computing Systems via Progress Balancing,&#8221;<\/a> Journal of Systems and Software, vol. 125, pp. 183\u2013196, Mar 2017<\/li>\n<li type=\"\">Sungju Huh, Jonghun Yoo, Myungsun Kim and Seongsoo Hong, <a href=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2015\/10\/ICDCS-2012.pdf\">&#8220;Providing Fair Share Scheduling on Multicore Cloud Servers via Virtual Runtime-based Task Migration Algorithm,&#8221;<\/a> Proceedings of the 32nd IEEE International Conference on Distributed Computing Systems (ICDCS 2012), pp. 606-614, Jun 2012<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div><\/div>\n<\/div>\n<p><!----------------------Topic 3 End-------------------><!----------------------Topic 4---------------------><\/p>\n<div style=\"text-align: justify; font-family: arial; font-size: 18pt; line-height: 100%;\"><div class=\"su-spoiler su-spoiler-style-simple su-spoiler-icon-plus\" data-scroll-offset=\"0\" data-anchor-in-url=\"no\"><div class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>4. Programming Language and Runtime for Future Autonomous Vehicles<\/div><div class=\"su-spoiler-content su-u-clearfix su-u-trim\"><!--A-end----><!--B-end----><\/p>\n<table border=\"0\" width=\"100%\" cellspacing=\"0\" cellpadding=\"0\">\n<tbody>\n<tr><!--A----><\/p>\n<td colspan=\"2\">\n<div style=\"text-align: justify; font-family: arial; font-size: 11pt; line-height: 100%;\"><b>Splash: stream processing language for real-time and embedded AI<\/b><!-- | <a href=\"http:\/\/redwood.snu.ac.kr\" target=\"_blank\" rel=\"noopener\">Project page<\/a>--><\/div>\n<\/td>\n<\/tr>\n<tr>\n<td valign=\"top\" width=\"20%\">\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\"><img decoding=\"async\" src=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2018\/06\/3.-Splash-stream-processing-language-for-real-time-and-embedded-AI.png\" alt=\"\" width=\"95%\" height=\"150\" name=\"\" \/><\/div>\n<\/td>\n<td valign=\"top\">\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\">In order to fully support Automotive AI, it is necessary to technically address the extra requirements that arise differently from those of conventional vehicles. Two of the most important requirements of Automotive AI are (1) real-time stream processing and (2) reliability. Currently, most companies and research institutes that develop autonomous vehicles rely on application developers to meet the above requirements. Since application developers often resort to a time consuming and iterative tuning process, this approach leads to inefficiencies in the development process and can lead to fatal injuries due to unintended circumstances that are overlooked during the tuning process. To overcome the limitation of the traditional development methodology, we propose the stream processing language named Splash. The Splash has five advantages. First, Splash visually expresses the flow of sensor stream data processing so that developers can easily grasp the complex interworking of a given AI program. Second, Splash let developers explicitly annotate the timing constraints of stream processing. Third, Splash allows developers to define exceptions and specify the handling of each exception. Fourth, Splash can describe complex synchronization issues of sensor fusion algorithms more perceptibly. Finally, Splash supports integration between domains that are developed with different programming paradigms such as data-driven and time-driven.<div class=\"su-list\" style=\"margin-left:0px\">\n<ul>\n<li><i class=\"sui sui-folder-o\" style=\"color:#333\"><\/i> <b>Publications<\/b><\/li>\n<li type=\"\">Hwancheol Kang, Cheonghwa Lee, Wooyoung Choi and Seongsoo Hong, <a href=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2021\/03\/21-06-17-UR-final.pdf\" target=\"_blank\" rel=\"noopener\">&#8220;Splash on ROS 2: A Runtime Software Framework for Autonomous Machines,&#8221;<\/a> The 18th International Conference on Ubiquitous Robots (UR 2021), pp. 557-564, Jul 2021<\/li>\n<li type=\"\">Soonhyun Noh, Cheonghwa Lee, Myungsun Kim and Seongsoo Hong, <a href=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2020\/04\/20-03-29-UR-Splash-sensor-fusion.pdf\" target=\"_blank\" rel=\"noopener\">&#8220;Programming Language Support for Multisensor Data Fusion: The Splash Approach<\/a>,&#8221; The 17th International Conference on Ubiquitous Robots (UR 2020), pp. 429-436, Jun 2020<\/li>\n<li type=\"\">Soonhyun Noh and Seongsoo Hong, <a href=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2019\/01\/19-03-02-UR-Splash.pdf\" target=\"_blank\" rel=\"noopener\">&#8220;Splash: A Graphical Programming Framework for an Autonomous Machine<\/a>,&#8221; The 16th International Conference on Ubiquitous Robots (UR 2019), pp. 660-666, Jun 2019<\/li>\n<li type=\"\">Soonhyun Noh and Seongsoo Hong, <a href=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2018\/05\/18-05-10-Splash-Abstract-Only_margin_corrected_final.pdf\">&#8220;Splash: Stream Processing Language for Autonomous Driving,&#8221;<\/a> The Workshop on Real-Time and Embedded AI for Autonomous Vehicles (WREAV), Jun 2018<\/li>\n<li><i class=\"sui sui-folder-o\" style=\"color:#333\"><\/i> <b>Projects<\/b><\/li>\n<li type=\"\">Application and validation of Splash-based development methodology for automotive AI applications, 2018-2020<\/li>\n<li type=\"\">Development of wide area driving environment awareness and cooperative driving technology which are based on V2X wireless communication, 2016-2019<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<\/td>\n<\/tr>\n<tr>\n<td colspan=\"2\"><!--\uacf5\ub780\n\n\n\n<hr \/>\n\n\n\n--><\/td>\n<\/tr>\n<tr><!--B-----><\/p>\n<td colspan=\"2\">\n<div style=\"text-align: justify; font-family: arial; font-size: 11pt; line-height: 100%;\"><b>Runtime SW stack for real-time and embedded AI<\/b><!-- | <a href=\"http:\/\/redwood.snu.ac.kr\" target=\"_blank\" rel=\"noopener\">Project page<\/a>--><\/div>\n<\/td>\n<\/tr>\n<tr>\n<td valign=\"top\" width=\"20%\">\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\"><img decoding=\"async\" src=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2018\/06\/3-B.png\" alt=\"\" width=\"95%\" height=\"150\" name=\"\" \/><\/div>\n<\/td>\n<td valign=\"top\">\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\">We build a runtime software stack that runs real-time and embedded AI applications developed using Splash. The proposed runtime is based on Linux and DDS (Data Distribution Service) that supports real-time publish-subscribe communication. We additionally incorporate Linux kernel optimization techniques in order to meet the non-functional requirements of the real-time and embedded AI applications.<div class=\"su-list\" style=\"margin-left:0px\">\n<ul>\n<li><i class=\"sui sui-folder-o\" style=\"color:#333\"><\/i> <b>Project<\/b><\/li>\n<li type=\"\">Development of SW platform for smart driving systems, 2016-2020<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div><\/div>\n<\/div>\n<p><!----------------------Topic 4 End-------------------><!----------------------Topic 5---------------------><\/p>\n<div style=\"text-align: justify; font-family: arial; font-size: 18pt; line-height: 100%;\"><div class=\"su-spoiler su-spoiler-style-simple su-spoiler-icon-plus\" data-scroll-offset=\"0\" data-anchor-in-url=\"no\"><div class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>5. Operating Systems for Advanced Vehicle Control<\/div><div class=\"su-spoiler-content su-u-clearfix su-u-trim\">\n<!------><\/p>\n<table border=\"0\" width=\"100%\" cellspacing=\"0\" cellpadding=\"0\"><!--A----><\/p>\n<tbody>\n<tr>\n<td colspan=\"2\">\n<div style=\"text-align: justify; font-family: arial; font-size: 11pt; line-height: 100%;\"><b>Providing OS support for integrated DCU-based platform for autonomous vehicles<\/b><!-- | <a href=\"http:\/\/redwood.snu.ac.kr\" target=\"_blank\" rel=\"noopener\">Project page<\/a>--><\/div>\n<\/td>\n<\/tr>\n<tr>\n<td valign=\"top\" width=\"20%\">\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\"><img decoding=\"async\" src=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2018\/06\/DCU.png\" alt=\"\" width=\"95%\" height=\"150\" name=\"\" \/><\/div>\n<\/td>\n<td valign=\"top\">\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\">With the advent of Automotive AI, separate ECUs in a vehicle are being merged into a single high performance DCU. Accordingly, we develop additional OS support for SW platform that runs on this DCU. We are currently working on three OS-level techniques for AUTOSAR platform: (1) multicore support for real-time computing, (2) shared memory management for stream processing and (3) three-level monitoring mechanism to increase reliability.<div class=\"su-list\" style=\"margin-left:0px\">\n<ul>\n<li><i class=\"sui sui-folder-o\" style=\"color:#333\"><\/i> <b>Projects<\/b><\/li>\n<li type=\"\">Development of a deterministic DCU platform with less than 1\u03bcs synchronization for autonomous driving system control, 2017-2021<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div><\/div>\n<\/div>\n<p><!----------------------Topic 5 End-------------------><!----------------------Topic 6---------------------><\/p>\n<div style=\"text-align: justify; font-family: arial; font-size: 18pt; line-height: 100%;\"><div class=\"su-spoiler su-spoiler-style-simple su-spoiler-icon-plus\" data-scroll-offset=\"0\" data-anchor-in-url=\"no\"><div class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>6. In-depth Kernel Optimization Techniques<\/div><div class=\"su-spoiler-content su-u-clearfix su-u-trim\"><!--B-end----><!--C-end----><!--D-end----><\/p>\n<table border=\"0\" width=\"100%\" cellspacing=\"0\" cellpadding=\"0\">\n<tbody>\n<tr><!--A-----><\/p>\n<td colspan=\"2\">\n<div style=\"text-align: justify; font-family: arial; font-size: 11pt; line-height: 100%;\"><b>Improving interactivity via cross-layer resource control and scheduling for Linux\/Android smartphones<\/b><!-- | <a href=\"http:\/\/redwood.snu.ac.kr\" target=\"_blank\" rel=\"noopener\">Project page<\/a>--><\/div>\n<\/td>\n<\/tr>\n<tr>\n<td valign=\"top\" width=\"20%\">\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\"><img decoding=\"async\" src=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2018\/06\/5-A.-Improving-interactivity-via-cross-layer-resource-control-and-scheduling-for-LinuxAndroid-smartphones.jpg\" alt=\"\" width=\"95%\" height=\"150\" name=\"\" \/><\/div>\n<\/td>\n<td valign=\"top\">\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\">Android smartphones are often reported to suffer from sluggish user interactions due to poor interactivity. This is partly because Android and its task scheduler, the completely fair scheduler (CFS), may incur perceptibly long response time to user-interactive tasks. Particularly, the Android framework cannot systemically favor user-interactive tasks over other background tasks since it does not distinguish between them. Furthermore, user-interactive tasks can suffer from high dispatch latency due to the non-preemptive nature of CFS. To address these problems, we present framework-assisted task characterization and virtual time-based CFS. The former is a cross-layer resource control mechanism between the Android framework and the underlying Linux kernel. It identifies user-interactive tasks at the framework-level, by using the notion of a user-interactive task chain. It then enables the kernel scheduler to selectively promote the priorities of worker tasks appearing in the task chain to reduce the preemption latency. The latter is a cross-layer refinement of CFS in terms of interactivity. It allows a task to be preempted at every predefined period. It also adjusts the virtual runtimes of the identified user-interactive tasks to ensure that they are always scheduled prior to the other tasks in the run-queue when they wake up. As a result, the dispatch latency of a user-interactive task is reduced to a small value.<div class=\"su-list\" style=\"margin-left:0px\">\n<ul>\n<li><i class=\"sui sui-folder-o\" style=\"color:#333\"><\/i> <b>Publications<\/b><\/li>\n<li type=\"\">Sungju Huh, Jonghun Yoo and Seongsoo Hong, <a href=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2015\/08\/sp-sjhuh-manuscript-draft.pdf\">&#8220;Cross-layer Resource Control and Scheduling for Improving Interactivity in Android,&#8221;<\/a> International Journal of Software: Practice and Experience, vol. 45, issue. 11, pp. 1549-1570, Nov 2015<\/li>\n<li type=\"\">Sungju Huh, Jonghun Yoo and Seongsoo Hong, <a href=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2015\/10\/RTCSA12-Android-Interactivity.pdf\">&#8220;Improving Interactivity via VT-CFS and Framework-assisted Task Characterization for Linux\/Android Smartphones,&#8221;<\/a> Proceedings of the 18th IEEE International Conference on Embedded and Real-Time Computing Systems and Applications (RTCSA 2012), pp. 250-259, Aug 2012<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<\/td>\n<\/tr>\n<tr><!--A-end----><\/p>\n<td colspan=\"2\"><!--\uacf5\ub780\n\n\n\n<hr \/>\n\n\n\n--><\/td>\n<\/tr>\n<tr><!--B-----><\/p>\n<td colspan=\"2\">\n<div style=\"text-align: justify; font-family: arial; font-size: 11pt; line-height: 100%;\"><b>Improving interactivity via kernel and middleware optimization for webOS TV<\/b><!-- | <a href=\"http:\/\/redwood.snu.ac.kr\" target=\"_blank\" rel=\"noopener\">Project page<\/a>--><\/div>\n<\/td>\n<\/tr>\n<tr>\n<td valign=\"top\" width=\"20%\">\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\"><img decoding=\"async\" src=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2018\/06\/webOS.jpg\" alt=\" \" width=\"95%\" height=\"150\" name=\"\" \/><\/div>\n<\/td>\n<td valign=\"top\">\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\">While analyzing the performance of webOS TV, we found that the TV channel switching time is significantly delayed during the booting process. This delay is caused by CPU resource contention between the channel switching threads and the other threads which perform the boot process. To solve this problem, we propose a cross-layer optimization technique that guarantees the channel switching threads to use sufficient CPU resources using Linux cgroup.<div class=\"su-list\" style=\"margin-left:0px\">\n<ul>\n<li><i class=\"sui sui-folder-o\" style=\"color:#333\"><\/i> <b>Project<\/b><\/li>\n<li type=\"\">Cross-layer optimization for webOS TV, 2013-2015<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<\/td>\n<\/tr>\n<tr>\n<td colspan=\"2\"><!--\uacf5\ub780\n\n\n\n<hr \/>\n\n\n\n--><\/td>\n<\/tr>\n<tr><!--C-----><\/p>\n<td colspan=\"2\">\n<div style=\"text-align: justify; font-family: arial; font-size: 11pt; line-height: 100%;\"><b>Reducing energy consumption of a modem via selective packet transmission delaying<\/b><!-- | <a href=\"http:\/\/redwood.snu.ac.kr\/wordpress\/index.php\/project_5-c\" target=\"_blank\" rel=\"noopener\">Project page<\/a>--><\/div>\n<\/td>\n<\/tr>\n<tr>\n<td valign=\"top\" width=\"20%\">\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\"><img decoding=\"async\" src=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2018\/06\/5-C.-Reducing-energy-consumption-of-a-modem-via-selective-packet-transmi....png\" alt=\" \" width=\"95%\" height=\"150\" name=\"\" \/><\/div>\n<\/td>\n<td valign=\"top\">\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\">Most energy-saving mechanisms for an LTE modem rely on a packet transmission delaying technique in that a smartphone attempts to reduce a modem\u2019s energy consumption by delaying transmissions of delay-tolerant packets and piggybacking them onto later packets. However, unconditional packet transmission delaying may lead to unanticipated energy loss of a modem since the exact radio resource control state of a modem is not considered. To address this problem, we propose a mechanism which selectively delays packet transmissions only if such delays are expected to achieve energy savings. In doing so, we make an estimated energy gain model which captures the modem\u2019s energy consumption for transmitting a current packet by considering the modem\u2019s state. Our mechanism consists of three key components: (1) deferrable packet identifier, (2) pattern-based next packet transmission predictor and (3) packet transmission time designator.<div class=\"su-list\" style=\"margin-left:0px\">\n<ul>\n<li><i class=\"sui sui-folder-o\" style=\"color:#333\"><\/i> <b>Publications<\/b><\/li>\n<li type=\"\">Daedong Park, Philkyue Shin and Seongsoo Hong , <a href=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2017\/07\/2017_IEEE-MDM.pdf\">&#8220;Reducing Energy Consumption of a Modem via Selective Packet Transmission Delaying,&#8221;<\/a> 18th IEEE International Conference on Mobile Data Management (MDM) , pp. 401-404, May 2017<\/li>\n<li><i class=\"sui sui-folder-o\" style=\"color:#333\"><\/i> <b>Project<\/b><\/li>\n<li type=\"\">Context-aware cross-layer protocol for 5G network, 2012-2014<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<\/td>\n<\/tr>\n<tr>\n<td colspan=\"2\"><!--\uacf5\ub780\n\n\n\n<hr \/>\n\n\n\n--><\/td>\n<\/tr>\n<tr><!--D-----><\/p>\n<td colspan=\"2\">\n<div style=\"text-align: justify; font-family: arial; font-size: 11pt; line-height: 100%;\"><b>Reducing energy consumption using Predictive On-Demand CPU frequency governor for Linux\/Android smartphones<\/b><!-- | <a href=\"http:\/\/redwood.snu.ac.kr\" target=\"_blank\" rel=\"noopener\">Project page<\/a>--><\/div>\n<\/td>\n<\/tr>\n<tr>\n<td valign=\"top\" width=\"20%\">\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\"><img decoding=\"async\" src=\"http:\/\/redwood.snu.ac.kr\/wordpress\/wp-content\/uploads\/2018\/06\/5-D.-Reducing-energy-consumption-using-Predictive-On-Demand-CPU-frequency-governor-for-LinuxAndroid-smartphones.jpg\" alt=\" \" width=\"95%\" height=\"150\" name=\"\" \/><\/div>\n<\/td>\n<td valign=\"top\">\n<div style=\"text-align: justify; font-family: arial; font-size: 10pt; line-height: 100%; word-spacing: 0px;\">Interactive Governor of Android smartphones adjusts CPU frequency according to system utilization and touch inputs. However, Interactive Governor has two limitations. First, it increases CPU when the system utilization is high even if a task that does not affect user responsiveness is being executed. Second, it does not take into account the characteristics of the currently running task. To overcome these limitations, we propose Predictive On-demand governor that adjusts CPU frequency based on the effective utilization and CPU-boundness of user-interactive tasks.<div class=\"su-list\" style=\"margin-left:0px\">\n<ul>\n<li><i class=\"sui sui-folder-o\" style=\"color:#333\"><\/i> <b>Project<\/b><\/li>\n<li type=\"\">Development of SW hotspot detection and SW simulation techiniques, 2014<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div><\/div>\n<\/div>\n<p><!----------------------Topic 6 End---------------------><\/p>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"footnotes":""},"class_list":["post-4559","page","type-page","status-publish","hentry"],"acf":[],"_links":{"self":[{"href":"https:\/\/redwood.snu.ac.kr\/wordpress\/index.php\/wp-json\/wp\/v2\/pages\/4559","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/redwood.snu.ac.kr\/wordpress\/index.php\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/redwood.snu.ac.kr\/wordpress\/index.php\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/redwood.snu.ac.kr\/wordpress\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/redwood.snu.ac.kr\/wordpress\/index.php\/wp-json\/wp\/v2\/comments?post=4559"}],"version-history":[{"count":477,"href":"https:\/\/redwood.snu.ac.kr\/wordpress\/index.php\/wp-json\/wp\/v2\/pages\/4559\/revisions"}],"predecessor-version":[{"id":8600,"href":"https:\/\/redwood.snu.ac.kr\/wordpress\/index.php\/wp-json\/wp\/v2\/pages\/4559\/revisions\/8600"}],"wp:attachment":[{"href":"https:\/\/redwood.snu.ac.kr\/wordpress\/index.php\/wp-json\/wp\/v2\/media?parent=4559"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}