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Copy on Write Based File Systems Performance Analysis and Implementation
Copy On Write Based File Systems Performance Analysis And Implementation Sakis Kasampalis Kongens Lyngby 2010 IMM-MSC-2010-63 Technical University of Denmark Department Of Informatics Building 321, DK-2800 Kongens Lyngby, Denmark Phone +45 45253351, Fax +45 45882673 [email protected] www.imm.dtu.dk Abstract In this work I am focusing on Copy On Write based file systems. Copy On Write is used on modern file systems for providing (1) metadata and data consistency using transactional semantics, (2) cheap and instant backups using snapshots and clones. This thesis is divided into two main parts. The first part focuses on the design and performance of Copy On Write based file systems. Recent efforts aiming at creating a Copy On Write based file system are ZFS, Btrfs, ext3cow, Hammer, and LLFS. My work focuses only on ZFS and Btrfs, since they support the most advanced features. The main goals of ZFS and Btrfs are to offer a scalable, fault tolerant, and easy to administrate file system. I evaluate the performance and scalability of ZFS and Btrfs. The evaluation includes studying their design and testing their performance and scalability against a set of recommended file system benchmarks. Most computers are already based on multi-core and multiple processor architec- tures. Because of that, the need for using concurrent programming models has increased. Transactions can be very helpful for supporting concurrent program- ming models, which ensure that system updates are consistent. Unfortunately, the majority of operating systems and file systems either do not support trans- actions at all, or they simply do not expose them to the users. -
Allgemeines Abkürzungsverzeichnis
Allgemeines Abkürzungsverzeichnis L. -
Active@ UNDELETE Documentation
Active @ UNDELETE Users Guide | Contents | 2 Contents Legal Statement.........................................................................................................5 Active@ UNDELETE Overview............................................................................. 6 Getting Started with Active@ UNDELETE.......................................................... 7 Active@ UNDELETE Views And Windows...................................................................................................... 7 Recovery Explorer View.......................................................................................................................... 8 Logical Drive Scan Result View..............................................................................................................9 Physical Device Scan View......................................................................................................................9 Search Results View...............................................................................................................................11 File Organizer view................................................................................................................................ 12 Application Log...................................................................................................................................... 13 Welcome View........................................................................................................................................14 Using -
Lenovo Bootable Media Creator Installation and User Guide
Lenovo Bootable Media Creator Installation and User Guide Version 12.3.0 Note Before using this information and the product it supports, read the information in Appendix C “Notices” on page 45. (August 2021) © Copyright Lenovo 2014, 2021. Portions © Copyright IBM Corporation 2009, 2021 LIMITED AND RESTRICTED RIGHTS NOTICE: If data or software is delivered pursuant to a General Services Administration (GSA) contract, use, reproduction, or disclosure is subject to restrictions set forth in Contract No. GS-35F- 05925. Tables 1. Acronyms . iii 6. Supported bootable environment. 7 2. Supported Lenovo platforms . 4 7. Main menus of ThinkSystem and System x 3. Supported IBM platforms. 5 (for Lenovo or IBM) . 25 4. Supported Storage platforms . 5 8. Configuration settings . 32 5. Operating systems supported by BoMC . 6 9. Return codes of commands . 40 © Copyright Lenovo 2014, 2021 ii iii Lenovo Bootable Media Creator Installation and User Guide Contents Tables . ii Creating bootable media for Lenovo servers and IBM servers . 11 About this publication . iii Creating bootable media for Storage systems . 15 Conventions and terminology . iii Updating existing bootable media. 16 Publications and related information. iv Web resources . iv Chapter 5. Using bootable media . 23 Starting bootable media from GUI. 23 Chapter 1. Technical overview . 1 Starting bootable media from text user interface . 24 Chapter 2. Hardware and software Chapter 6. Troubleshooting and requirements. 3 support . 27 Hardware requirements. 3 Limitations and problems . 27 Supported server models . 3 Workarounds. 28 EFI Boot . 5 Lenovo XClarity Essentials Bootable Media IPv6 enablement. 5 Creator log file . 28 Software requirements . 6 Appendix A. Accessibility features Supported operating systems . -
Enhancing the Accuracy of Synthetic File System Benchmarks Salam Farhat Nova Southeastern University, [email protected]
Nova Southeastern University NSUWorks CEC Theses and Dissertations College of Engineering and Computing 2017 Enhancing the Accuracy of Synthetic File System Benchmarks Salam Farhat Nova Southeastern University, [email protected] This document is a product of extensive research conducted at the Nova Southeastern University College of Engineering and Computing. For more information on research and degree programs at the NSU College of Engineering and Computing, please click here. Follow this and additional works at: https://nsuworks.nova.edu/gscis_etd Part of the Computer Sciences Commons Share Feedback About This Item NSUWorks Citation Salam Farhat. 2017. Enhancing the Accuracy of Synthetic File System Benchmarks. Doctoral dissertation. Nova Southeastern University. Retrieved from NSUWorks, College of Engineering and Computing. (1003) https://nsuworks.nova.edu/gscis_etd/1003. This Dissertation is brought to you by the College of Engineering and Computing at NSUWorks. It has been accepted for inclusion in CEC Theses and Dissertations by an authorized administrator of NSUWorks. For more information, please contact [email protected]. Enhancing the Accuracy of Synthetic File System Benchmarks by Salam Farhat A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor in Philosophy in Computer Science College of Engineering and Computing Nova Southeastern University 2017 We hereby certify that this dissertation, submitted by Salam Farhat, conforms to acceptable standards and is fully adequate in scope and quality to fulfill the dissertation requirements for the degree of Doctor of Philosophy. _____________________________________________ ________________ Gregory E. Simco, Ph.D. Date Chairperson of Dissertation Committee _____________________________________________ ________________ Sumitra Mukherjee, Ph.D. Date Dissertation Committee Member _____________________________________________ ________________ Francisco J. -
CD-ROM, CD-R, CD-RW, and DVD-ROM Drives) Are the Hardware Devices That Read Computer Data from Disks
A Brief History of CD/DVD The first disc that could be written and read by optical means (using light as a medium) was developed by James T. Russell. In the late 1960s, Russell created a system that recorded, stored, and played audio/video data using light rather than the traditional contact methods, which could easily damage the disks during playback. Russell developed a photosensitive disc that stored data as 1 micron-wide dots of light and dark. The dots were read by a laser, converted to an electrical signal, and then to audio or visual display for playback. Russell's own company manufactured the first disc player in 1980, although the technology never reached the marketplace until Philips and Sony developed the technology. In late 1982, Philips and Sony released the first of the compact disc (CD) formats, which they then called CD-DA (digital audio). In the years since, format has followed format as the original companies and other industry members developed more adaptations of the original specifications. Digital Versatile disc (DVD) had its beginning in 1994, when two formats, Super disc (SD) and Multimedia CD (MMCD) were introduced. Promoters of the competing technologies failed to reach an agreement on a single standard until 1996, when DVD was selected as a convergence format. DVD has, in the few years since, grown to include variations that do anything that CD does, and more efficiently. Standardization and compatibility issues aside, DVD is well-placed to supplant CD. Magnetic vs Optical Media Optical media are storage media that hold information in digital form and that are written and read by a laser; these media include all the various CD and DVD variations, as well as optical jukeboxes and autochangers. -
Active @ UNDELETE Users Guide | TOC | 2
Active @ UNDELETE Users Guide | TOC | 2 Contents Legal Statement..................................................................................................4 Active@ UNDELETE Overview............................................................................. 5 Getting Started with Active@ UNDELETE........................................................... 6 Active@ UNDELETE Views And Windows......................................................................................6 Recovery Explorer View.................................................................................................... 7 Logical Drive Scan Result View.......................................................................................... 7 Physical Device Scan View................................................................................................ 8 Search Results View........................................................................................................10 Application Log...............................................................................................................11 Welcome View................................................................................................................11 Using Active@ UNDELETE Overview................................................................. 13 Recover deleted Files and Folders.............................................................................................. 14 Scan a Volume (Logical Drive) for deleted files..................................................................15 -
Ext4 File System and Crash Consistency
1 Ext4 file system and crash consistency Changwoo Min 2 Summary of last lectures • Tools: building, exploring, and debugging Linux kernel • Core kernel infrastructure • Process management & scheduling • Interrupt & interrupt handler • Kernel synchronization • Memory management • Virtual file system • Page cache and page fault 3 Today: ext4 file system and crash consistency • File system in Linux kernel • Design considerations of a file system • History of file system • On-disk structure of Ext4 • File operations • Crash consistency 4 File system in Linux kernel User space application (ex: cp) User-space Syscalls: open, read, write, etc. Kernel-space VFS: Virtual File System Filesystems ext4 FAT32 JFFS2 Block layer Hardware Embedded Hard disk USB drive flash 5 What is a file system fundamentally? int main(int argc, char *argv[]) { int fd; char buffer[4096]; struct stat_buf; DIR *dir; struct dirent *entry; /* 1. Path name -> inode mapping */ fd = open("/home/lkp/hello.c" , O_RDONLY); /* 2. File offset -> disk block address mapping */ pread(fd, buffer, sizeof(buffer), 0); /* 3. File meta data operation */ fstat(fd, &stat_buf); printf("file size = %d\n", stat_buf.st_size); /* 4. Directory operation */ dir = opendir("/home"); entry = readdir(dir); printf("dir = %s\n", entry->d_name); return 0; } 6 Why do we care EXT4 file system? • Most widely-deployed file system • Default file system of major Linux distributions • File system used in Google data center • Default file system of Android kernel • Follows the traditional file system design 7 History of file system design 8 UFS (Unix File System) • The original UNIX file system • Design by Dennis Ritche and Ken Thompson (1974) • The first Linux file system (ext) and Minix FS has a similar layout 9 UFS (Unix File System) • Performance problem of UFS (and the first Linux file system) • Especially, long seek time between an inode and data block 10 FFS (Fast File System) • The file system of BSD UNIX • Designed by Marshall Kirk McKusick, et al. -
MSD FATFS Users Guide
Freescale MSD FATFS Users Guide Document Number: MSDFATFSUG Rev. 0 02/2011 How to Reach Us: Home Page: www.freescale.com E-mail: [email protected] USA/Europe or Locations Not Listed: Freescale Semiconductor Technical Information Center, CH370 1300 N. Alma School Road Chandler, Arizona 85224 +1-800-521-6274 or +1-480-768-2130 [email protected] Europe, Middle East, and Africa: Information in this document is provided solely to enable system and Freescale Halbleiter Deutschland GmbH software implementers to use Freescale Semiconductor products. There are Technical Information Center no express or implied copyright licenses granted hereunder to design or Schatzbogen 7 fabricate any integrated circuits or integrated circuits based on the 81829 Muenchen, Germany information in this document. +44 1296 380 456 (English) +46 8 52200080 (English) Freescale Semiconductor reserves the right to make changes without further +49 89 92103 559 (German) notice to any products herein. Freescale Semiconductor makes no warranty, +33 1 69 35 48 48 (French) representation or guarantee regarding the suitability of its products for any particular purpose, nor does Freescale Semiconductor assume any liability [email protected] arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation consequential or Japan: incidental damages. “Typical” parameters that may be provided in Freescale Freescale Semiconductor Japan Ltd. Semiconductor data sheets and/or specifications can and do vary in different Headquarters applications and actual performance may vary over time. All operating ARCO Tower 15F parameters, including “Typicals”, must be validated for each customer 1-8-1, Shimo-Meguro, Meguro-ku, application by customer’s technical experts. -
Heritage Ascential Software Portfolio, Now Available in Passport Advantage, Delivers Trustable Information for Enterprise Initiatives
Software Announcement July 18, 2006 Heritage Ascential software portfolio, now available in Passport Advantage, delivers trustable information for enterprise initiatives Overview structures ranging from simple to highly complex. It manages data At a glance With the 2005 acquisition of arriving in real time as well as data Ascential Software Corporation, received on a periodic or scheduled IBM software products acquired IBM added a suite of offerings to its basis and enables companies to from Ascential Software information management software solve large-scale business problems Corporation are now available portfolio that helps you profile, through high-performance through IBM Passport Advantage cleanse, and transform any data processing of massive data volumes. under new program numbers and across the enterprise in support of A WebSphere DataStage Enterprise a new, simplified licensing model. strategic business initiatives such as Edition license grants entitlement to You can now license the following business intelligence, master data media for both WebSphere programs for distributed platforms: DataStage Server and WebSphere management, infrastructure • consolidation, and data governance. DataStage Enterprise Edition. Core product: WebSphere The heritage Ascential programs in Datastore Enterprise Edition, this announcement are now WebSphere RTI enables WebSphere WebSphere QualityStage available through Passport DataStage jobs to participate in a Enterprise Edition, WebSphere Advantage under a new, service-oriented architecture (SOA) -
CD Burning with Mac OS X
CD Burning with Mac OS X Software: Macintosh OS X and iTunes Platform: Macintosh Connection:N/A Availability: Purchase/Labs Why create a CD-ROM? CD-ROMs are a low-cost media that can hold large amounts of information in a variety of formats. Also, nearly every computer today has a CD-ROM drive, so your data can be transported easily. While most people are introduced to CD-ROM burning as a way to create custom audio CDs, CD-ROMs are well suited for archiving and backing up personal data. In the classroom, existing electronic resources can be easily incorporated into a CD-ROM. Step 1. Decide what kind of CD you want to create Macintosh Files & Folders - This is the easiest method for burning for Mac. Macintosh Volume - This allows you to make an exact duplicate of another CD ISO 9660 - PC Format. Make sure fi le names are legal. Macintosh/ISO 9660 - “Hybrid” CD for both Macintosh and PC platforms Audio - For creating music CDs Step 2. Planning Gather your content This includes all the material you want to burn on the CD-ROM. Archive word documents, e-mail, presentations, PDF fi les and other traditional computer fi les. You may also need to collect any media fi les such as graphics, audio fi les, or movie fi les. In some cases, you may want to convert your fi les from one fi le type to another prior to creating your CD. For example, you may want to convert a word document to a PDF document prior to distribution. -
The Linux Device File-System
The Linux Device File-System Richard Gooch EMC Corporation [email protected] Abstract 1 Introduction All Unix systems provide access to hardware via de- vice drivers. These drivers need to provide entry points for user-space applications and system tools to access the hardware. Following the \everything is a file” philosophy of Unix, these entry points are ex- posed in the file name-space, and are called \device The Device File-System (devfs) provides a power- special files” or \device nodes". ful new device management mechanism for Linux. Unlike other existing and proposed device manage- This paper discusses how these device nodes are cre- ment schemes, it is powerful, flexible, scalable and ated and managed in conventional Unix systems and efficient. the limitations this scheme imposes. An alternative mechanism is then presented. It is an alternative to conventional disc-based char- acter and block special devices. Kernel device drivers can register devices by name rather than de- vice numbers, and these device entries will appear in the file-system automatically. 1.1 Device numbers Devfs provides an immediate benefit to system ad- ministrators, as it implements a device naming scheme which is more convenient for large systems Conventional Unix systems have the concept of a (providing a topology-based name-space) and small \device number". Each instance of a driver and systems (via a device-class based name-space) alike. hardware component is assigned a unique device number. Within the kernel, this device number is Device driver authors can benefit from devfs by used to refer to the hardware and driver instance.