• Title/Summary/Keyword: Disk Failure

Search Result 121, Processing Time 0.03 seconds

HRSF: Single Disk Failure Recovery for Liberation Code Based Storage Systems

  • Li, Jun;Hou, Mengshu
    • Journal of Information Processing Systems
    • /
    • v.15 no.1
    • /
    • pp.55-66
    • /
    • 2019
  • Storage system often applies erasure codes to protect against disk failure and ensure system reliability and availability. Liberation code that is a type of coding scheme has been widely used in many storage systems because its encoding and modifying operations are efficient. However, it cannot effectively achieve fast recovery from single disk failure in storage systems, and has great influence on recovery performance as well as response time of client requests. To solve this problem, in this paper, we present HRSF, a Hybrid Recovery method for solving Single disk Failure. We present the optimal algorithm to accelerate failure recovery process. Theoretical analysis proves that our scheme consumes approximately 25% less amount of data read than the conventional method. In the evaluation, we perform extensive experiments by setting different number of disks and chunk sizes. The results show that HRSF outperforms conventional method in terms of the amount of data read and failure recovery time.

Influence of the variation of its geometry on the disk failure (디스크 형상 변화에 따른 파손에 끼치는 영향)

  • Kim, Jong-Man;Hwang, Hyo-Kune;Dan, Byung-Ju;Kim, Wae-Yeul;Lee, Jin-Woo
    • Proceedings of the KSME Conference
    • /
    • 2004.04a
    • /
    • pp.31-35
    • /
    • 2004
  • The speed competition of optical disk drive has been accelerated with the fast advancement of its storage density and data transmission technology. The continuous increase of the spinning speed of CD meets the unexpected and catastrophic failure of disk during the operation. The effect of its thickness and outer radius of disk were investigated to reduce stresses and J-integral around the crack tip. The effect of its thickness was considered ahead of the crack tip. In the effect of outer radius of disk, linear elastic fracture mechanics was used to obtain the critical crack length, which indicates the onset length for unstable crack growth. This approach is so significant as to detect the growing crack by disk drive before the catastrophic failure, which will provide the standard size of its safety for high-speed disk drive.

  • PDF

Stiction and AE Characteristics of Hard Disk Drive under Various Environmental Conditions (환경 조건에 따른 하드디스크의 Stiction 및 AE 특성)

  • 박용식;성인하;김대은
    • Tribology and Lubricants
    • /
    • v.17 no.1
    • /
    • pp.1-9
    • /
    • 2001
  • Hard disk drives operate in various environmental conditions. Thus, it is necessary to assess the reliability of the head/disk interface under these conditions. In this work, stiction and acoustic emission signals were investigated under different temperature, humidity, and ambient pressure conditions. Also, track average amplitude was observed for disk failure in N$_2$environment. It is shown that failure of the head/disk interface occurs more readily at high temperature and low ambient pressure conditions.

Effect of Particulate Contamination on the Friction and Wear of Head-Disk Interface with Picoslider (오염입자가 Picoslider의 헤드-디스크 인테페이스 마찰 마모에 미치는 영향)

  • ;Bharat Bhushan
    • Tribology and Lubricants
    • /
    • v.16 no.5
    • /
    • pp.395-402
    • /
    • 2000
  • The effect of particulate contamination on friction and wear between a negative-pressure picoslider and a laser-textured disk was studied. Particles of different concentrations, materials and sizes were injected to the head-disk interface (HDI), consisting of disks with various textures, at the same speed. In a contaminated environment, durability of head-disk interface gradually decreased as the particle concentration increased. Large particles caused HDI failure early and resulted in an extensive damage to the slider and disk surfaces. Hard particles also caused HDI failure earlier and damages more extensive than soft ones. Based on the test results, mechanisms of HDI failure with picoslider were presented.

Failure Analysis of Optical Disk Drives Using the Vibration Signal Analysis (진동신호분석을 통한 광디스크 드라이브의 고장원인분석)

  • Park Youngpil;Shin Changho;Chung Jintai
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.29 no.7 s.238
    • /
    • pp.1028-1034
    • /
    • 2005
  • In this paper, the failure analysis of an optical disk drive is carried out and the limit ranges of the misalignment f3r the higher performance are presented. Since optical disks are removable from optical disk drive, the translational and angular misalignments, which causes read/write errors, always exist. Therefore, the limit ranges of the misalignment should be investigated. For this reason, the failure analysis by the vibration analysis is studied. The influences of the misalignment are tested by the aging test. And the limit ranges of the misalignment are proposed for the reliability of optical disk drives.

An Analysis on the Impact Characteristics in a Layered Half-Space with a Cathing Region (코팅부 균열의 충격특성 해석)

  • 이강요;권순만
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 1995.10a
    • /
    • pp.664-667
    • /
    • 1995
  • The purpose of this paper is to consider the disk failure phenomenon based on the second kind Fredholm integral equation and numerical inversion of Laplace transform when the head hit disk asperities at HDI under antiplane impact loading. The model for analysis is a two layeered half-space with a circumferential surface edge crack. The optimum design parameters to reduce the disk failure due to impact are presented

  • PDF

Industry-University Cooperation Research Activities Through Idea Factory (Optimized Modeling in Butterfly Valve Disk by Creative Selection in Material) (Idea Factory를 통한 산학 협력 연구 활동 (소재의 적절한 선정을 통한 버터플라이 밸브 디스크의 최적화 모델링))

  • Kim, Yun-Hae;Park, Chang-Wook;Bae, Chang-Won;Kim, Han-Sol;Jung, Min-Kyo
    • Journal of Engineering Education Research
    • /
    • v.19 no.6
    • /
    • pp.44-48
    • /
    • 2016
  • This research is one of the Industry-University cooperation in idea factory of Korea Maritime and Ocean University. Idea factory of Korea Maritime and Ocean University is trying to train creative talented students and discover ingenious ideas. The contents are consisted of the possibility for the replacement of a metal valve disk to composite valve disk in butterfly valve based on the diversification. Purpose in this study is to predict failure field by each fly by appling Tsai-Wu Failure Index.

Level Conversion Scheme for Improving Performance of RAID 5 on Single Disk Failure (단일디스크 고장시 RAID 5의 성능개선을 위한 레벨 전환 기법)

  • Jeon, Sang-Hoon;Chung, Hyun-Sik
    • Journal of the Korea Society of Computer and Information
    • /
    • v.4 no.2
    • /
    • pp.8-18
    • /
    • 1999
  • It is very important to recover data immediately at a single disk failure for critical applications such as multimedia storage systems. real-time systems and so on. As an efficient solution, this paper proposes that RAID level conversion scheme to improve the performance before a failed disk is replaced with a new disk. By using this scheme, it does not require an additional disk to recover data. Comparing with previous studies, this scheme is appropriate to low cost system that has not additional redundant device. The performance of proposed scheme is evaluated and analyzed with that of RAID level 5 for various requested sizes through the simulation. The results show that the performance of the proposed scheme is improved up to 20 percents compared with that of RAID level 5 at the failure mode and 80 percents at reconfigured mode.

  • PDF

Surface Failure Phenomenon Due to Head/Disk Contact (헤드/디스크의 접촉으로 인한 표면파손 현상)

  • Chung, Koo-Hyun;Moon, Jae-Taek;Lee, Jung-Kyu;Kim, Dae-Eun
    • Proceedings of the KSME Conference
    • /
    • 2001.06c
    • /
    • pp.322-326
    • /
    • 2001
  • Hard disk drive(HDD) consists of a head/slider system which flies over the magnetic disk at an extremely low height. As the density of HDD increases the flying height of the head needs to be decreased. This increases the chance for contact between the slider and the disk. This paper addresses some key issues related to surface failure characteristics of HDD. It is shown that flying behavior of the slider during contact-start-stop cycle can be analyzed based on different regimes of air film lubrication, experimental methods for identifying the underlying mechanisms and improving the reliability of HDD are discussed.

  • PDF

The Data Transmission of Image Storage System of PACS (PACS내 영상저장 장치의 데이터 전송)

  • Cho, EuyHyun;Park, Jeongkyu
    • Journal of the Korean Society of Radiology
    • /
    • v.12 no.6
    • /
    • pp.785-791
    • /
    • 2018
  • Recently, Disk array is widely used as a long term storage device in PACS, but reliability is not enough in relation to annual failure rate of disk. Between October 2016 and February 2017, we scanned the serial port of the hard disk while reading or storing medical images on a PACS reader. The data rate was calculated from the data stored in HDD 99ea that were used in the PCAS image storage device and in HDD 101ea that were used in the Personal Computer. When a CT image was read from a PACS reader, Reading was 87.8% and Writing was 12.2% in units of several tens of megabytes or less. When the CT image was stored in the PACS reader, Reading was 11.4% and Writing was 88.6% in units of several tens of megabytes or less. While reading the excel file on the personal computer, Reading was 75% and Writing was 25% in less than 3 MB, and In the process of storing the excel file on the personal computer, Reading was carried out by 38% and Writing was carreid out 62% in the units of 3 MB or less. The transfer rate of the hard disk used in the PACS image storage device was 10 GB/h, and the transfer rate per hour of the hard disk of the personal computer was 5 GB / h. Annual failure rate of hard disk of image storage system is 0.97 ~ 1.13%, Annual failure rate of Hard Disk of personal computer is 0.97 ~ 1.13%. the higher transfer rate is, the higher annual failure rate is. These results will be used as a basis for predicting the life expectancy of the hard disk and the annual failure rate.