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Userland Tools and Techniques for Board Bring up and Systems Integration
Userland Tools and Techniques for Board Bring Up and Systems Integration ELC 2012 HY Research LLC http://www.hy-research.com/ Feb 5, 2012 (C) 2012 HY Research LLC Agenda * Introduction * What? * Why bother with userland? * Common SoC interfaces * Typical Scenario * Kernel setup * GPIO/UART/I2C/SPI/Other * Questions HY Research LLC http://www.hy-research.com/ Feb 5, 2012 (C) 2012 HY Research LLC Introduction * SoC offer a lot of integrated functionality * System designs differ by outside parts * Most mobile systems are SoC * "CPU boards" for SoCs * Available BSP for starting * Vendor or other sources * Common Unique components * Memory (RAM) * Storage ("flash") * IO * Displays HY Research LLC * Power supplies http://www.hy-research.com/ Feb 5, 2012 (C) 2012 HY Research LLC What? * IO related items * I2C * SPI * UART * GPIO * USB HY Research LLC http://www.hy-research.com/ Feb 5, 2012 (C) 2012 HY Research LLC Why userland? * Easier for non kernel savy * Quicker turn around time * Easier to debug * Often times available already Sample userland from BSP/LSP vendor * Kernel driver is not ready HY Research LLC http://www.hy-research.com/ Feb 5, 2012 (C) 2012 HY Research LLC Common SoC interfaces Most SoC have these and more: * Pinmux * UART * GPIO * I2C * SPI * USB * Not discussed: Audio/Displays HY Research LLC http://www.hy-research.com/ Feb 5, 2012 (C) 2012 HY Research LLC Typical Scenario Custom board: * Load code/Bring up memory * Setup memory controller for part used * Load Linux * Toggle lines on board to verify Prototype based on demo/eval board: * Start with board at a shell prompt * Get newly attached hw to work HY Research LLC http://www.hy-research.com/ Feb 5, 2012 (C) 2012 HY Research LLC Kernel Setup Additions to typical configs: * Enable UART support (typically done already) * Enable I2C support along with drivers for the SoC * (CONFIG_I2C + other) * Enable SPIdev * (CONFIG_SPI + CONFIG_SPI_SPIDEV) * Add SPIDEV to board file * Enable GPIO sysfs * (CONFIG_GPIO + other + CONFIG_GPIO_SYSFS) * Enable USB * Depends on OTG vs normal, etc. -
MOAT004 1 Eprint Cs.DC/0306067 Computing in High Energy and Nuclear Physics, 24-28 March 2003, La Jolla, California Resources
Computing in High Energy and Nuclear Physics, 24-28 March 2003, La Jolla, California The AliEn system, status and perspectives P. Buncic Institut für Kernphysik, August-Euler-Str. 6, D-60486 Frankfurt, Germany and CERN, 1211, Geneva 23, Switzerland A. J. Peters, P.Saiz CERN, 1211, Geneva 23, Switzerland In preparation of the experiment at CERN's Large Hadron Collider (LHC), the ALICE collaboration has developed AliEn, a production environment that implements several components of the Grid paradigm needed to simulate, reconstruct and analyse data in a distributed way. Thanks to AliEn, the computing resources of a Virtual Organization can be seen and used as a single entity – any available node can execute jobs and access distributed datasets in a fully transparent way, wherever in the world a file or node might be. The system is built aroun d Open Source components, uses the Web Services model and standard network protocols to implement the computing platform that is currently being used to produce and analyse Monte Carlo data at over 30 sites on four continents. Several other HEP experiments as well as medical projects (EU MammoGRID, INFN GP -CALMA) have expressed their interest in AliEn or some components of it. As progress is made in the definition of Grid standards and interoperability, our aim is to interface AliEn to emerging products from both Europe and the US. In particular, it is our intention to make AliEn services compatible with the Open Grid Services Architecture (OGSA). The aim of this paper is to present the current AliEn architecture and outline its future developments in the light of emerging standards. -
CERIAS Tech Report 2017-5 Deceptive Memory Systems by Christopher N
CERIAS Tech Report 2017-5 Deceptive Memory Systems by Christopher N. Gutierrez Center for Education and Research Information Assurance and Security Purdue University, West Lafayette, IN 47907-2086 DECEPTIVE MEMORY SYSTEMS ADissertation Submitted to the Faculty of Purdue University by Christopher N. Gutierrez In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy December 2017 Purdue University West Lafayette, Indiana ii THE PURDUE UNIVERSITY GRADUATE SCHOOL STATEMENT OF DISSERTATION APPROVAL Dr. Eugene H. Spa↵ord, Co-Chair Department of Computer Science Dr. Saurabh Bagchi, Co-Chair Department of Computer Science Dr. Dongyan Xu Department of Computer Science Dr. Mathias Payer Department of Computer Science Approved by: Dr. Voicu Popescu by Dr. William J. Gorman Head of the Graduate Program iii This work is dedicated to my wife, Gina. Thank you for all of your love and support. The moon awaits us. iv ACKNOWLEDGMENTS Iwould liketothank ProfessorsEugeneSpa↵ord and SaurabhBagchi for their guidance, support, and advice throughout my time at Purdue. Both have been instru mental in my development as a computer scientist, and I am forever grateful. I would also like to thank the Center for Education and Research in Information Assurance and Security (CERIAS) for fostering a multidisciplinary security culture in which I had the privilege to be part of. Special thanks to Adam Hammer and Ronald Cas tongia for their technical support and Thomas Yurek for his programming assistance for the experimental evaluation. I am grateful for the valuable feedback provided by the members of my thesis committee, Professor Dongyen Xu, and Professor Math ias Payer. -
Oracle® Linux 7 Release Notes for Oracle Linux 7.2
Oracle® Linux 7 Release Notes for Oracle Linux 7.2 E67200-22 March 2021 Oracle Legal Notices Copyright © 2015, 2021 Oracle and/or its affiliates. This software and related documentation are provided under a license agreement containing restrictions on use and disclosure and are protected by intellectual property laws. Except as expressly permitted in your license agreement or allowed by law, you may not use, copy, reproduce, translate, broadcast, modify, license, transmit, distribute, exhibit, perform, publish, or display any part, in any form, or by any means. Reverse engineering, disassembly, or decompilation of this software, unless required by law for interoperability, is prohibited. The information contained herein is subject to change without notice and is not warranted to be error-free. If you find any errors, please report them to us in writing. If this is software or related documentation that is delivered to the U.S. Government or anyone licensing it on behalf of the U.S. Government, then the following notice is applicable: U.S. GOVERNMENT END USERS: Oracle programs (including any operating system, integrated software, any programs embedded, installed or activated on delivered hardware, and modifications of such programs) and Oracle computer documentation or other Oracle data delivered to or accessed by U.S. Government end users are "commercial computer software" or "commercial computer software documentation" pursuant to the applicable Federal Acquisition Regulation and agency-specific supplemental regulations. As such, the use, reproduction, duplication, release, display, disclosure, modification, preparation of derivative works, and/or adaptation of i) Oracle programs (including any operating system, integrated software, any programs embedded, installed or activated on delivered hardware, and modifications of such programs), ii) Oracle computer documentation and/or iii) other Oracle data, is subject to the rights and limitations specified in the license contained in the applicable contract. -
Flexible Lustre Management
Flexible Lustre management Making less work for Admins ORNL is managed by UT-Battelle for the US Department of Energy How do we know Lustre condition today • Polling proc / sysfs files – The knocking on the door model – Parse stats, rpc info, etc for performance deviations. • Constant collection of debug logs – Heavy parsing for common problems. • The death of a node – Have to examine kdumps and /or lustre dump Origins of a new approach • Requirements for Linux kernel integration. – No more proc usage – Migration to sysfs and debugfs – Used to configure your file system. – Started in lustre 2.9 and still on going. • Two ways to configure your file system. – On MGS server run lctl conf_param … • Directly accessed proc seq_files. – On MSG server run lctl set_param –P • Originally used an upcall to lctl for configuration • Introduced in Lustre 2.4 but was broken until lustre 2.12 (LU-7004) – Configuring file system works transparently before and after sysfs migration. Changes introduced with sysfs / debugfs migration • sysfs has a one item per file rule. • Complex proc files moved to debugfs • Moving to debugfs introduced permission problems – Only debugging files should be their. – Both debugfs and procfs have scaling issues. • Moving to sysfs introduced the ability to send uevents – Item of most interest from LUG 2018 Linux Lustre client talk. – Both lctl conf_param and lctl set_param –P use this approach • lctl conf_param can set sysfs attributes without uevents. See class_modify_config() – We get life cycle events for free – udev is now involved. What do we get by using udev ? • Under the hood – uevents are collect by systemd and then processed by udev rules – /etc/udev/rules.d/99-lustre.rules – SUBSYSTEM=="lustre", ACTION=="change", ENV{PARAM}=="?*", RUN+="/usr/sbin/lctl set_param '$env{PARAM}=$env{SETTING}’” • You can create your own udev rule – http://reactivated.net/writing_udev_rules.html – /lib/udev/rules.d/* for examples – Add udev_log="debug” to /etc/udev.conf if you have problems • Using systemd for long task. -
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. -
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 -
HTTP-FUSE Xenoppix
HTTP-FUSE Xenoppix Kuniyasu Suzaki† Toshiki Yagi† Kengo Iijima† Kenji Kitagawa†† Shuichi Tashiro††† National Institute of Advanced Industrial Science and Technology† Alpha Systems Inc.†† Information-Technology Promotion Agency, Japan††† {k.suzaki,yagi-toshiki,k-iijima}@aist.go.jp [email protected], [email protected] Abstract a CD-ROM. Furthermore it requires remaking the entire CD-ROM when a bit of data is up- dated. The other solution is a Virtual Machine We developed “HTTP-FUSE Xenoppix” which which enables us to install many OSes and ap- boots Linux, Plan9, and NetBSD on Virtual plications easily. However, that requires in- Machine Monitor “Xen” with a small bootable stalling virtual machine software. (6.5MB) CD-ROM. The bootable CD-ROM in- cludes boot loader, kernel, and miniroot only We have developed “Xenoppix” [1], which and most part of files are obtained via Internet is a combination of CD/DVD bootable Linux with network loopback device HTTP-FUSE “KNOPPIX” [2] and Virtual Machine Monitor CLOOP. It is made from cloop (Compressed “Xen” [3, 4]. Xenoppix boots Linux (KNOP- Loopback block device) and FUSE (Filesys- PIX) as Host OS and NetBSD or Plan9 as Guest tem USErspace). HTTP-FUSE CLOOP can re- OS with a bootable DVD only. KNOPPIX construct a block device from many small block is advanced in automatic device detection and files of HTTP servers. In this paper we describe driver integration. It prepares the Xen environ- the detail of the implementation and its perfor- ment and Guest OSes don’t need to worry about mance. lack of device drivers. -
[13주차] Sysfs and Procfs
1 7 Computer Core Practice1: Operating System Week13. sysfs and procfs Jhuyeong Jhin and Injung Hwang Embedded Software Lab. Embedded Software Lab. 2 sysfs 7 • A pseudo file system provided by the Linux kernel. • sysfs exports information about various kernel subsystems, HW devices, and associated device drivers to user space through virtual files. • The mount point of sysfs is usually /sys. • sysfs abstrains devices or kernel subsystems as a kobject. Embedded Software Lab. 3 How to create a file in /sys 7 1. Create and add kobject to the sysfs 2. Declare a variable and struct kobj_attribute – When you declare the kobj_attribute, you should implement the functions “show” and “store” for reading and writing from/to the variable. – One variable is one attribute 3. Create a directory in the sysfs – The directory have attributes as files • When the creation of the directory is completed, the directory and files(attributes) appear in /sys. • Reference: ${KERNEL_SRC_DIR}/include/linux/sysfs.h ${KERNEL_SRC_DIR}/fs/sysfs/* • Example : ${KERNEL_SRC_DIR}/kernel/ksysfs.c Embedded Software Lab. 4 procfs 7 • A special filesystem in Unix-like operating systems. • procfs presents information about processes and other system information in a hierarchical file-like structure. • Typically, it is mapped to a mount point named /proc at boot time. • procfs acts as an interface to internal data structures in the kernel. The process IDs of all processes in the system • Kernel provides a set of functions which are designed to make the operations for the file in /proc : “seq_file interface”. – We will create a file in procfs and print some data from data structure by using this interface. -
Refs: Is It a Game Changer? Presented By: Rick Vanover, Director, Technical Product Marketing & Evangelism, Veeam
Technical Brief ReFS: Is It a Game Changer? Presented by: Rick Vanover, Director, Technical Product Marketing & Evangelism, Veeam Sponsored by ReFS: Is It a Game Changer? OVERVIEW Backing up data is more important than ever, as data centers store larger volumes of information and organizations face various threats such as ransomware and other digital risks. Microsoft’s Resilient File System or ReFS offers a more robust solution than the old NT File System. In fact, Microsoft has stated that ReFS is the preferred data volume for Windows Server 2016. ReFS is an ideal solution for backup storage. By utilizing the ReFS BlockClone API, Veeam has developed Fast Clone, a fast, efficient storage backup solution. This solution offers organizations peace of mind through a more advanced approach to synthetic full backups. CONTEXT Rick Vanover discussed Microsoft’s Resilient File System (ReFS) and described how Veeam leverages this technology for its Fast Clone backup functionality. KEY TAKEAWAYS Resilient File System is a Microsoft storage technology that can transform the data center. Resilient File System or ReFS is a valuable Microsoft storage technology for data centers. Some of the key differences between ReFS and the NT File System (NTFS) are: ReFS provides many of the same limits as NTFS, but supports a larger maximum volume size. ReFS and NTFS support the same maximum file name length, maximum path name length, and maximum file size. However, ReFS can handle a maximum volume size of 4.7 zettabytes, compared to NTFS which can only support 256 terabytes. The most common functions are available on both ReFS and NTFS. -
High Velocity Kernel File Systems with Bento
High Velocity Kernel File Systems with Bento Samantha Miller, Kaiyuan Zhang, Mengqi Chen, and Ryan Jennings, University of Washington; Ang Chen, Rice University; Danyang Zhuo, Duke University; Thomas Anderson, University of Washington https://www.usenix.org/conference/fast21/presentation/miller This paper is included in the Proceedings of the 19th USENIX Conference on File and Storage Technologies. February 23–25, 2021 978-1-939133-20-5 Open access to the Proceedings of the 19th USENIX Conference on File and Storage Technologies is sponsored by USENIX. High Velocity Kernel File Systems with Bento Samantha Miller Kaiyuan Zhang Mengqi Chen Ryan Jennings Ang Chen‡ Danyang Zhuo† Thomas Anderson University of Washington †Duke University ‡Rice University Abstract kernel-level debuggers and kernel testing frameworks makes this worse. The restricted and different kernel programming High development velocity is critical for modern systems. environment also limits the number of trained developers. This is especially true for Linux file systems which are seeing Finally, upgrading a kernel module requires either rebooting increased pressure from new storage devices and new demands the machine or restarting the relevant module, either way on storage systems. However, high velocity Linux kernel rendering the machine unavailable during the upgrade. In the development is challenging due to the ease of introducing cloud setting, this forces kernel upgrades to be batched to meet bugs, the difficulty of testing and debugging, and the lack of cloud-level availability goals. support for redeployment without service disruption. Existing Slow development cycles are a particular problem for file approaches to high-velocity development of file systems for systems. -
Release 0.5.0 Will Mcgugan
PyFilesystem Documentation Release 0.5.0 Will McGugan Aug 09, 2017 Contents 1 Guide 3 1.1 Introduction...............................................3 1.2 Getting Started..............................................4 1.3 Concepts.................................................5 1.4 Opening Filesystems...........................................7 1.5 Filesystem Interface...........................................7 1.6 Filesystems................................................9 1.7 3rd-Party Filesystems.......................................... 10 1.8 Exposing FS objects........................................... 10 1.9 Utility Modules.............................................. 11 1.10 Command Line Applications....................................... 11 1.11 A Guide For Filesystem Implementers.................................. 14 1.12 Release Notes.............................................. 16 2 Code Documentation 17 2.1 fs.appdirfs................................................ 17 2.2 fs.base.................................................. 18 2.3 fs.browsewin............................................... 30 2.4 fs.contrib................................................. 30 2.5 fs.errors.................................................. 32 2.6 fs.expose................................................. 34 2.7 fs.filelike................................................. 40 2.8 fs.ftpfs.................................................. 42 2.9 fs.httpfs.................................................. 43 2.10 fs.memoryfs..............................................