NDLI: Design issues for a shingled write disk system

Content Provider	IEEE Xplore Digital Library
Author	Amer, A. Long, D.D.E. Miller, E.L. Pâris, J.-F. Schwarz, S.J.T.
Copyright Year	2010
Description	Author affiliation: University of California Santa Cruz, CA (Long, D.D.E.; Miller, E.L.) \|\| Universidad Católica del Uruguay Montevideo, Uruguay (Schwarz, S.J.T.) \|\| University of Houston Houston, TX (Pâris, J.-F.) \|\| Santa Clara University Santa Clara, CA (Amer, A.)
Abstract	If the data density of magnetic disks is to continue its current 30–50% annual growth, new recording techniques are required. Among the actively considered options, shingled writing is currently the most attractive one because it is the easiest to implement at the device level. Shingled write recording trades the inconvenience of the inability to update in-place for a much higher data density by a using a different write technique that overlaps the currently written track with the previous track. Random reads are still possible on such devices, but writes must be done largely sequentially. In this paper, we discuss possible changes to disk-based data structures that the adoption of shingled writing will require. We first explore disk structures that are optimized for large sequential writes with little or no sequential writing, even of metadata structures, while providing acceptable read performance. We also examine the usefulness of non-volatile RAM and the benefits of object-based interfaces in the context of shingled disks. Finally, through the analysis of recent device traces, we demonstrate the surprising stability of written device blocks, with general purpose workloads showing that more than 93% of device blocks remain unchanged over a day, and that for more specialized workloads less than 0.5% of a shingled-write disk's capacity would be needed to hold randomly updated blocks.
Starting Page	1
Ending Page	12
File Size	1263324
Page Count	12
File Format	PDF
ISBN	9781424471522
e-ISBN	9781424471539
DOI	10.1109/MSST.2010.5496991
Language	English
Publisher	Institute of Electrical and Electronics Engineers, Inc. (IEEE)
Publisher Date	2010-05-03
Publisher Place	USA
Access Restriction	Subscribed
Rights Holder	Institute of Electrical and Electronics Engineers, Inc. (IEEE)
Subject Keyword	Writing Disk recording Nonvolatile memory Random access memory Magnetic recording Disk drives Magnetic heads Magnetic fields Data structures Stability analysis
Content Type	Text
Resource Type	Article

Sl.	Authority	Responsibilities	Communication Details
1	Ministry of Education (GoI), Department of Higher Education	Sanctioning Authority	https://www.education.gov.in/ict-initiatives
2	Indian Institute of Technology Kharagpur	Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project	https://www.iitkgp.ac.in
3	National Digital Library of India Office, Indian Institute of Technology Kharagpur	The administrative and infrastructural headquarters of the project	Dr. B. Sutradhar bsutra@ndl.gov.in
4	Project PI / Joint PI	Principal Investigator and Joint Principal Investigators of the project	Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon
5	Website/Portal (Helpdesk)	Queries regarding NDLI and its services	support@ndl.gov.in
6	Contents and Copyright Issues	Queries related to content curation and copyright issues	content@ndl.gov.in
7	National Digital Library of India Club (NDLI Club)	Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach	clubsupport@ndl.gov.in
8	Digital Preservation Centre (DPC)	Assistance with digitizing and archiving copyright-free printed books	dpc@ndl.gov.in
9	IDR Setup or Support	Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops	idr@ndl.gov.in