NetApp - Research Papers http://www.netapp.com/us/library/research-papers Research Papers Full Library http://www.netapp.com/us/library/research-papers/ View the entire NetApp Research Paper Library Thu, 20 Dec 2012 07:34:09 PST http://www.netapp.com/us/library/research-papers/ Private Clouds - Storage Architectures Can Maximize Efficiencies http://www.netapp.com/us/library/research-papers/rp-storage-architectures-en.html In this Thought Leadership Paper, Forrester finds that companies lack clear understanding about private clouds and tend to underestimate the key components—storage among them—that are required to achieve maximum benefit from a cloud strategy. This analyst paper takes steps to clarify the private cloud concept and explain the importance of storage to successful cloud computing implementations. Mon, 06 Jun 2011 05:00:00 PDT http://www.netapp.com/us/library/research-papers/rp-storage-architectures-en.html Private Clouds - Storage Architectures Can Maximize Efficiencies http://www.netapp.net/us/library/research-papers/rp-storage-architectures.html In this Thought Leadership Paper, Forrester finds that companies lack clear understanding about private clouds and tend to underestimate the key components—storage among them—that are required to achieve maximum benefit from a cloud strategy. This analyst paper takes steps to clarify the private cloud concept and explain the importance of storage to successful cloud computing implementations. Wed, 01 Jun 2011 05:00:00 PDT http://www.netapp.net/us/library/research-papers/rp-storage-architectures.html Microsoft Private Clouds and NetApp Reference Architecture http://www.netapp.com/us/library/research-papers/rp-microsoft-private-clouds.html This document provides a blueprint for private IaaS implementations on the Microsoft Hyper-V and System Center platform. This document is for customers and partner architects seeking to design private cloud implementations on the NetApp platform. Tue, 01 Mar 2011 02:29:00 PST http://www.netapp.com/us/library/research-papers/rp-microsoft-private-clouds.html NetApp Unified Ethernet Storage Evaluation http://www.netapp.com/us/library/research-papers/rp-unified-networking-evaluation.html Demartek conducted a performance evaluation of NetApp's unified ethernet storage solution in January 2010. NetApp is the first storage vendor to support traditional Fibre Channel, FCoE, iSCSI, NFS and CIFS in a single storage controller and high-availability system. This 14-page report provides test results from the evaluation along with graphs and tables. Mon, 18 Jan 2010 12:15:00 PST http://www.netapp.com/us/library/research-papers/rp-unified-networking-evaluation.html NetApp Thin Provisioning - Doing More With Less http://www.netapp.com/us/library/research-papers/rp-silverton-thin-provisioning.html Reducing or deferring a datacenter’s capital and/or operational expense has become a paramount concern in today’s challenging economic climate. Many storage vendors’ promote functionality and features that can purportedly provide potential cost savings but few actually deliver on this promise. However, one proven feature offered in the open system marketplace since the early 2000’s is thin provisioning. Mon, 11 Jan 2010 12:15:00 PST http://www.netapp.com/us/library/research-papers/rp-silverton-thin-provisioning.html The Move to Desktop Virtualization http://www.netapp.com/us/library/research-papers/rp-computerworld-desktop-virtualization.html In April 2009, Computerworld invited IT and business leaders to participate in a survey on desktop virtualization. The survey was fielded via targeted broadcasts to Computerworld customers, as well as through an invitation on Computerworld.com. The goal of the survey was to understand key drivers for implementing Virtual Desktop Infrastructure (VDI) or hosted virtual desktops, as well as top concerns in this area. Mon, 01 Jun 2009 12:15:00 PDT http://www.netapp.com/us/library/research-papers/rp-computerworld-desktop-virtualization.html A Highly Accurate Method for Assessing Reliability of Redundant Arrays of Inexpensive Disks (RAID) http://www.netapp.com/us/library/research-papers/rp-0046.html The statistical bases for current models of RAID reliability are reviewed, and a highly accurate alternative is provided and justified. This new model corrects statistical errors associated with the pervasive assumption that system (RAID group) times-to-failure follow a homogeneous Poisson process, and it corrects errors associated with the assumption that the time-to-failure and time-to-restore distributions are exponentially distributed. Statistical justification for the new model uses theories of reliability of repairable systems. Four critical component distributions are developed from field data. These distributions are for times to catastrophic failure, reconstruction and restoration, read errors, and disk data scrubs. Model results have been verified to predict between 2 and 1,500 times as many double disk failures as estimates made using the mean time-to-data-loss (MTTDL) method. Model results are compared to system-level field data for a RAID group of 14 drives and show excellent correlation and greater accuracy than either MTTDL or Markov models. Fri, 23 Jan 2009 12:00:00 PST http://www.netapp.com/us/library/research-papers/rp-0046.html Measurement and Analysis of Large-Scale Network File SystemWorkloads http://www.netapp.com/us/library/research-papers/rp-0042.html In this paper we present the analysis of two large-scale
network file system workloads. We measured CIFS traffic
for two enterprise-class file servers deployed in the
NetApp data center for a three month period. One file
server was used by marketing, sales, and finance departments
and the other by the engineering department.
Together these systems represent over 22TB of storage
used by over 1500 employees, making this the first ever
large-scale study of the CIFS protocol.
Wed, 18 Jun 2008 11:02:00 PDT http://www.netapp.com/us/library/research-papers/rp-0042.html
NetApp Technical Journal: Spring 2008 http://www.netapp.com/us/library/research-papers/rp-0044.html A collection of the latest NetApp Research Papers bound in a single volume. Sun, 01 Jun 2008 11:02:00 PDT http://www.netapp.com/us/library/research-papers/rp-0044.html MultiVizArch: Multiple Graphical Layouts for Visualizing Software Architecture http://www.netapp.com/us/library/research-papers/rp-0039.html This article presents an automated technique for visualizing large software architectures using multiple graphical representations, including multi-dimensional scaling, 2-D grid, and spiral layouts. We describe how our software visualization methods were applied to the Network Appliance operating system known as Data ONTAP 7G (ONTAP). We show how each method can be applied to comprehend a specific aspect of ONTAP. This approach can be used by software engineers, architects, and developers to better understand the architecture of their code. Mon, 31 Mar 2008 11:02:00 PDT http://www.netapp.com/us/library/research-papers/rp-0039.html Don't Blame Disks for Every Storage Subsystem Failure http://www.netapp.net/us/library/research-papers/rp-0038.html This report analyzes the failure characteristics of storage subsystems. More specifically, we analyzed the NetApp AutoSupport logs collected from about 39,000 storage systems commercially deployed at various customer sites. The data set covers a period of 44 months and includes about 1,800,000 disks hosted in about 155,000 storage shelf enclosures. Thu, 27 Mar 2008 11:02:00 PDT http://www.netapp.net/us/library/research-papers/rp-0038.html SWEEPER: An Efficient Disaster Recovery Point Identification Mechanism http://www.netapp.net/us/library/research-papers/rp-0037.html In this paper, we present the design and implementation of SWEEPER architecture and backup copy selection algorithms that specifically tackle the problem of quickly and systematically identifying a good recovery point. Fri, 29 Feb 2008 11:02:00 PST http://www.netapp.net/us/library/research-papers/rp-0037.html Parity Lost and Parity Regained http://www.netapp.net/us/library/research-papers/rp-0034.html We introduce and apply a formal method of analyzing the design of data protection strategies. Specifically, we use moDelete checking to evaluate whether common protection techniques used in parity-based RAID systems are sufficient in light of the increasingly complex failure modes of modern disk drives. Thu, 28 Feb 2008 11:02:00 PST http://www.netapp.net/us/library/research-papers/rp-0034.html Are Disks the Dominant Contributor for Storage Failures? http://www.netapp.com/us/library/research-papers/rp-0035.html This paper analyzes the failure characteristics of storage subsystems. More speci cally, we analyzed the storage logs collected from about 39,000 storage systems commercially deployed at various customer sites. The data set covers a period of 44 months and includes about 1,800,000 disks hosted in about 155,000 storage shelf enclosures. Thu, 28 Feb 2008 11:02:00 PST http://www.netapp.com/us/library/research-papers/rp-0035.html An Analysis of Data Corruption in the Storage Stack http://www.netapp.net/us/library/research-papers/rp-0036.html In this paper, we present the first large-scale study of data corruption. We analyze corruption instances recorded in production storage systems containing a total of 1.53 million disk drives, over a period of 41 months. We study three classes of corruption: checksum mismatches, identity discrepancies, and parity inconsistencies Thu, 28 Feb 2008 11:02:00 PST http://www.netapp.net/us/library/research-papers/rp-0036.html Pergamum: Replacing Tape with Energy Efficient, Reliable, Disk-Based Archival Storage http://www.netapp.net/us/library/research-papers/rp-0032.html Pergamum is a distributed network of intelligent, disk-based, storage appliances that stores data reliably and energy-efficiently. While existing MAID systems keep disks idle to save energy, Pergamum adds NVRAM at each node to store data signatures, metadata, and other small items, allowing deferred writes, metadata requests and inter-disk data verification to be performed while the disk is powered off. Wed, 27 Feb 2008 11:02:00 PST http://www.netapp.net/us/library/research-papers/rp-0032.html AWOL: An Adaptive Write Optimizations Layer http://www.netapp.net/us/library/research-papers/rp-0033.html Operating system memory managers fail to consider the population of read versus write pages in the buffer pool or outstanding I/O requests when writing dirty pages to disk or network file systems. This leads to bursty I/O patterns, which stall processes reading data and reduce the efficiency of storage. We address these limitations by adaptively allocating memory between write buffering and read caching and by writing dirty pages to disk opportunistically before the operating system submits them for write-back. Wed, 27 Feb 2008 11:02:00 PST http://www.netapp.net/us/library/research-papers/rp-0033.html Disk Drive Vintage and Its Effect on Reliability http://www.netapp.com/us/library/research-papers/rp-0030.html Field failure data for 3 disk drive families from 3 drive manufacturers is analyzed. The analyses illustrate the effects of design and manufacturing process improvements implemented throughout the drive’s production life on the reliability of disk drives. Sat, 23 Feb 2008 02:23:00 PST http://www.netapp.com/us/library/research-papers/rp-0030.html Standardizing Storage Clusters http://www.netapp.net/us/library/research-papers/rp-0029.html Will pNFS become the new standard for parallel data access? Sat, 01 Sep 2007 11:02:00 PDT http://www.netapp.net/us/library/research-papers/rp-0029.html An Analysis of Latent Sector Errors in Disk Drives http://www.netapp.com/us/library/research-papers/rp-0027.html Our study analyzes data collected from production storage systems over 32 months across 1.53 million disks (both nearline and enterprise class). We analyze factors that im- pact latent sector errors, observe trends, and explore their implications on the design of reliability mechanisms in storage systems. Thu, 12 Jul 2007 11:27:00 PDT http://www.netapp.com/us/library/research-papers/rp-0027.html DiffArchViz: A Tool to Visualize Correspondence Between Multiple Representations of a Software Architecture http://www.netapp.net/us/library/research-papers/rp-0026.html We integrate the Multi-Dimensional Scaling (MDS) algorithm into a visualization technique for converting raw source code into patterns that capture the software architecture. Individual components are drawn using graphical “glyphs” that vary their spatial position, color, and texture properties to encode each component’s attribute values. The result is a display that can be used by viewers to rapidly and accurately analyze, explore, compare, and discover within the software architecture. Mon, 25 Jun 2007 11:54:00 PDT http://www.netapp.net/us/library/research-papers/rp-0026.html SoftArchViz: An Automated Approach to Visualizing Software http://www.netapp.com/us/library/research-papers/rp-0025.html This paper presents a programmatic mechanism for visualizing large software architectures using Multi-Dimensional Scaling. Mon, 25 Jun 2007 11:43:00 PDT http://www.netapp.com/us/library/research-papers/rp-0025.html SoftArchViz: A Software Architecture Visualization Tool http://www.netapp.net/us/library/research-papers/rp-0040.html This tool presents a technique for visualizing large software architectures using the Multi-Dimensional Scaling algorithm. Our visualization tool, SoftArchViz, can be used to study different architectural views that represent different attributes of the software components. We visualize the architecture of the Network Appliance operating system known as Data ONTAP 7G (ONTAP) using graphical “glyphs” representing individual software components that vary their spatial position, color, and texture properties to encode the components’ attribute values. We also represent the correspondence in the architecture at different stages of the development cycle and thereby identify all the components that changed and the extent of those changes, and thus evaluate the actual implementation of the architecture. Mon, 25 Jun 2007 11:02:00 PDT http://www.netapp.net/us/library/research-papers/rp-0040.html POTSHARDS: Secure Long-Term Storage Without Encryption http://www.netapp.com/us/library/research-papers/rp-0024.html We have developed POTSHARDS, an archival storage system that provides longterm security for data with very long lifetimes without using encryption. Secrecy is achieved by using provably secure secret splitting and spreading the resulting shares across separately-managed archives. Sun, 17 Jun 2007 12:59:00 PDT http://www.netapp.com/us/library/research-papers/rp-0024.html Policy-Driven Management of Data Sets http://www.netapp.com/us/library/research-papers/rp-0045.html Contemporary storage systems separate the management of data from the management of the underlying physical storage media used to store that data. This separation is artificial and increases the overall burden of managing such systems. We propose a new management layer that unifies data and storage management without any loss of control over either the data or the storage. Fri, 01 Jun 2007 11:02:00 PDT http://www.netapp.com/us/library/research-papers/rp-0045.html Data ONTAP GX: A Scalable Storage Cluster http://www.netapp.com/us/library/research-papers/rp-0023.html Data ONTAP GX is a clustered Network Attached File server composed of a number of cooperating filers. Each filer manages its own local file system, which consists of a number of disconnected flexible volumes. Thu, 01 Feb 2007 11:47:00 PST http://www.netapp.com/us/library/research-papers/rp-0023.html