고성능 PC 클러스터 시스템을 위한 VIA 기반 RDMA 메커니즘 구현

정인형,정상화,박세진 한국정보과학회 2004 정보과학회논문지 : 시스템 및 이론 Vol.31 No.11

The traditional communication protocols such as TCP/IP are not suitable for PC cluster systems because of their high software processing overhead. To eliminate this overhead, industry leaders have defined the Virtual Interface Architecture (VIA). VIA provides two different data transfer mechanisms, a traditional Send/Receive model and the Remote Direct Memory Access (RDMA) model. RDMA is extremely efficient way to reduce software overhead because it can bypass the OS and use the network interface controller (NIC) directly for communication, also bypass the CPU on the remote host. In this paper, we have implemented VIA-based RDMA mechanism in hardware. Compared to the traditional Send/Receive model, the RDMA mechanism improves latency and bandwidth. Our RDMA mechanism can also communicate without using remote CPU cycles. Our experimental results show a minimum latency of 12.5㎲ and a maximum bandwidth of 95.5MB/s. As a result, our RDMA mechanism allows PC cluster systems to have a high performance communication method. PC 클러스터 상에서 기존의 TCP/IP와 같은 통신 프로토콜의 높은 소프트웨어 오버헤드를 제거하기 위한 노력으로 산업계 표준으로 Virtual Interface Architecture(VIA)가 제안되었다. VIA가 제공하는 통신 방식중, Remote Direct Memory Access(RDMA) 방식은 커널과 리모트 노드의 개입 없이 통신을 가능하게 함으로써 PC 클러스터 시스템에 효율적인 통신 방법을 제공한다. 본 논문에서는 VIA 기반 RDMA 메커니즘을 하드웨어로 구현하였다. 일반적인 송수신방식과 비교하여 본 논문에서 구현한 RDMA 메커니즘은 커널의 개입 없이 무복사 통신을 가능하게 하며, 또한 리모트 노드의 CPU의 사용 없이 통신을 수행할 수 있다. 실험결과, RDMA를 하드웨어 VIA 기반 네트워크 어댑터상에 구현함으로써 최소 12.5㎲의 지연시간, 최대 95.5MB/s의 대역폭을 얻을 수 있었다. 결과적으로 본 논문에서 구현한 VIA 기반 RDAM 메커니즘은 PC 클러스터 시스템에 효율적인 통신 방법을 제공한다.

고성능 PC 클러스터 시스템을 위한 VIA 기반 RDMA 메커니즘 구현

정인형(In-Hyung Jung),정상화(Sang-Hwa Chung),박세진(Sejin Park) 한국정보과학회 2004 정보과학회논문지 : 시스템 및 이론 Vol.31 No.11·12

The traditional communication protocols such as TCP/IP are not suitable for PC cluster systems because of their high software processing overhead. To eliminate this overhead, industry leaders have defined the Virtual Interface Architecture (VIA). VIA provides two different data transfer mechanisms, a traditional Send/Receive model and the Remote Direct Memory Access (RDMA) model. RDMA is extremely efficient way to reduce software overhead because it can bypass the OS and use the network interface controller (NIC) directly for communication, also bypass the CPU on the remote host. In this paper, we have implemented VIA-based RDMA mechanism in hardware. Compared to the traditional Send/Receive model, the RDMA mechanism improves latency and bandwidth. Our RDMA mechanism can also communicate without using remote CPU cycles. Our experimental results show a minimum latency of 12.5㎲ and a maximum bandwidth of 95.5MB/s. As a result, our RDMA mechanism allows PC cluster systems to have a high performance communication method. PC 클러스터 상에서 기존의 TCP/IP와 같은 통신 프로토콜의 높은 소프트웨어 오버헤드를 제거하기 위한 노력으로 산업계 표준으로 Virtual Interface Architecture(VIA)가 제안되었다. VIA가 제공하는 통신 방식중, Remote Direct Memory Access(RDMA) 방식은 커널과 리모트 노드의 개입 없이 통신을 가능하게 함으로써 PC 클러스터 시스템에 효율적인 통신 방법을 제공한다. 본 논문에서는 VIA 기반 RDMA 메커니즘을 하드웨어로 구현하였다. 일반적인 송수신방식과 비교하여 본 논문에서 구현한 RDMA 메커니즘은 커널의 개입 없이 무복사 통신을 가능하게 하며, 또한 리모트 노드의 CPU의 사용 없이 통신을 수행할 수 있다. 실험결과, RDMA를 하드웨어 VIA 기반 네트워크 어댑터상에 구현함으로써 최소 12.5㎲의 지연시간, 최대 95.5MB/s의 대역폭을 얻을 수 있었다. 결과적으로 본 논문에서 구현한 VIA 기반 RDAM 메커니즘은 PC 클러스터 시스템에 효율적인 통신 방법을 제공한다.

두부외상후 정신장애 감정환자에 관한 임상적 연구

정인형,강민희 大韓神經精神醫學會 1995 신경정신의학 Vol.34 No.6

Objects : The authors analyzed retrospectively 64 cases of head injury referred from the court, caretaker, or insurance company with purpose of evaluation of mental disability. Premorbid chararcteristics, information about accidents, information about assessments, psychopathology, KWIS and MMSE score and factors affecting the results of assessment were studied. Methods : We collected data through patient's hospital record and expert opinion in writing. Results : 1) The incidence of head injuries tended to be high in male, socially-active age group and laborers. 2) Automobile accident was the most common cause of the brain injury. 3) The time interval from accident to assessment of were very wide from 0% to 100%. The mean result of the assessment was 36.16±24.48%. 4) Memory impairment was the most common symptom of head injury patients and was followed by headache/dizziness, apathy, and irritability 5) There were statistically significant differences in the mean scores of MMSE total and many subtest scores among three disability result groups. There were statistically significant differences in mean scores of full scale and several subtests of KWIS between high disability evaluation group and low and moderate disability evaluation groups. 6) Three were statistically significant differences in MMSE total score, and many subtests between dementias and organic personality disorder and organic mental disorder, NOS patients. There were statistically significant differenced in mean scores of full scale and several subtests of KWIS between dementias and organic personality disorder and organic mental disorder, NOS patients. 7) Language and praxis in MMSE and diagnosis were the most important factors affecting the result of assessment.

뉴럴 네트워크를 활용한 가상현실 아바타의 전신 동작 생성 방법의 연구 소개 및 비교

정인형(Inhyung Jung),박경주(Kyoungju Park) 한국HCI학회 2024 한국HCI학회 학술대회 Vol.2024 No.1

본 논문은 VR 환경에서 헤드셋과 콘트롤러 센서 정보와 뉴럴 네트워크를 이용하여 아바타의 전신 자세를 생성하는 최신 연구 동향에 대한 소개와 각 연구들의 특징과 결과를 비교하였다.

정상인에서 부분적 수면박탈이 수면구조에 미치는 영향

왕성근,이정규,이충숙,최하석,유남재,정인형,이선우 충남대학교 의과대학 지역사회의학연구소 1992 충남의대잡지 Vol.19 No.2

To identify the effects of partial sleep deprivation on the sleep structure, the authors performed polysomnographic study for 9 healthy young adults. The subjects were college students, ranging in age from 20 to 25 years, without personal past or present histories of medical, neurological, or psychiatric illness and suffering from current sleep disturbance or parasomomnias. Sleep records were analyzed according to the criteria of Rechtschaffen and Kales' manual and tried paired t-test. The results were summarized as follows. 1. As for sleep parameters, total sleep time(TST), REM latency and REM duration were not changed significantly during deprivation period and recovery period compared with baseline. Sleep efficiency increased significantly during deprivation period and recovery period compaired with baseline, and sleep latency and WASO were shortened significantly during deprivation period and recovery period compared with baseline. 2. As for sleep structure, 1) The absolute value(minutes) of stage 1 decreased significantly during deprivation period and first recovery night compared with baseline, and the relative value(percentage) of stage 1 decreased significantly during deprivation period and recovery period compared with baseline. 2) The absolute value(minutes) of stage 2 decreased significantly during deprivation period compared with baseline, and the relative value(percentage) of stage 2 decreased significantly during deprivation period and first recovery night compared with baseline. 3) The absolute value(minutes) of slow wave sleep were not changed significantly during deprivation period and recovery period compared with baseline, and the relative value(percentage) of slow wave sleep increased significantly during recovery period compared with baseline. 4) The absolute value(minutes) of REM sleep decreased significantly during deprivation period compared with baseline, and the relative value(percentage) of REM sleep decreased significantly in the first deprivation night but, were not changed significantly during recovery period compared with baseline.