Unit 5: Memory Organizations
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Section 10 Flash Technology
10 FLASH TECHNOLOGY Overview Flash memory technology is a mix of EPROM and EEPROM technologies. The term “flash” was chosen because a large chunk of memory could be erased at one time. The name, therefore, distinguishes flash devices from EEPROMs, where each byte is erased individually. Flash memory technology is today a mature technology. Flash memory is a strong com- petitor to other memories such as EPROMs, EEPROMs, and to some DRAM applications. Figure 10-1 shows the density comparison of a flash versus other memories. 64M 16M 4M DRAM/EPROM 1M SRAM/EEPROM Density 256K Flash 64K 1980 1982 1984 1986 1988 1990 1992 1994 1996 Year Source: Intel/ICE, "Memory 1996" 18613A Figure 10-1. Flash Density Versus Other Memory How the Device Works The elementary flash cell consists of one transistor with a floating gate, similar to an EPROM cell. However, technology and geometry differences between flash devices and EPROMs exist. In particular, the gate oxide between the silicon and the floating gate is thinner for flash technology. It is similar to the tunnel oxide of an EEPROM. Source and INTEGRATED CIRCUIT ENGINEERING CORPORATION 10-1 Flash Technology drain diffusions are also different. Figure 10-2 shows a comparison between a flash cell and an EPROM cell with the same technology complexity. Due to thinner gate oxide, the flash device will be more difficult to process. CMOS Flash Cell CMOS EPROM Cell Mag. 10,000x Mag. 10,000x Flash Memory Cell – Larger transistor – Thinner floating gate – Thinner oxide (100-200Å) Photos by ICE 17561A Figure 10-2. -
Chapter 12: Mass-Storage Systems
Chapter 12: Mass-Storage Systems Overview of Mass Storage Structure Disk Structure Disk Attachment Disk Scheduling Disk Management Swap-Space Management RAID Structure Disk Attachment Stable-Storage Implementation Tertiary Storage Devices Operating System Issues Performance Issues Objectives Describe the physical structure of secondary and tertiary storage devices and the resulting effects on the uses of the devices Explain the performance characteristics of mass-storage devices Discuss operating-system services provided for mass storage, including RAID and HSM Overview of Mass Storage Structure Magnetic disks provide bulk of secondary storage of modern computers Drives rotate at 60 to 200 times per second Transfer rate is rate at which data flow between drive and computer Positioning time (random-access time) is time to move disk arm to desired cylinder (seek time) and time for desired sector to rotate under the disk head (rotational latency) Head crash results from disk head making contact with the disk surface That’s bad Disks can be removable Drive attached to computer via I/O bus Busses vary, including EIDE, ATA, SATA, USB, Fibre Channel, SCSI Host controller in computer uses bus to talk to disk controller built into drive or storage array Moving-head Disk Mechanism Overview of Mass Storage Structure (Cont.) Magnetic tape Was early secondary-storage medium Relatively permanent and holds large quantities of data Access time slow Random access ~1000 times slower than disk Mainly used for backup, storage of infrequently-used data, transfer medium between systems Kept in spool and wound or rewound past read-write head Once data under head, transfer rates comparable to disk 20-200GB typical storage Common technologies are 4mm, 8mm, 19mm, LTO-2 and SDLT Disk Structure Disk drives are addressed as large 1-dimensional arrays of logical blocks, where the logical block is the smallest unit of transfer. -
Nanotechnology ? Nram (Nano Random Access
International Journal Of Engineering Research and Technology (IJERT) IFET-2014 Conference Proceedings INTERFACE ECE T14 INTRACT – INNOVATE - INSPIRE NANOTECHNOLOGY – NRAM (NANO RANDOM ACCESS MEMORY) RANJITHA. T, SANDHYA. R GOVERNMENT COLLEGE OF TECHNOLOGY, COIMBATORE 13. containing elements, nanotubes, are so small, NRAM technology will Abstract— NRAM (Nano Random Access Memory), is one of achieve very high memory densities: at least 10-100 times our current the important applications of nanotechnology. This paper has best. NRAM will operate electromechanically rather than just been prepared to cull out answers for the following crucial electrically, setting it apart from other memory technologies as a questions: nonvolatile form of memory, meaning data will be retained even What is NRAM? when the power is turned off. The creators of the technology claim it What is the need of it? has the advantages of all the best memory technologies with none of How can it be made possible? the disadvantages, setting it up to be the universal medium for What is the principle and technology involved in NRAM? memory in the future. What are the advantages and features of NRAM? The world is longing for all the things it can use within its TECHNOLOGY palm. As a result nanotechnology is taking its head in the world. Nantero's technology is based on a well-known effect in carbon Much of the electronic gadgets are reduced in size and increased nanotubes where crossed nanotubes on a flat surface can either be in efficiency by the nanotechnology. The memory storage devices touching or slightly separated in the vertical direction (normal to the are somewhat large in size due to the materials used for their substrate) due to Van der Waal's interactions. -
AXP Internal 2-Apr-20 1
2-Apr-20 AXP Internal 1 2-Apr-20 AXP Internal 2 2-Apr-20 AXP Internal 3 2-Apr-20 AXP Internal 4 2-Apr-20 AXP Internal 5 2-Apr-20 AXP Internal 6 Class 6 Subject: Computer Science Title of the Book: IT Planet Petabyte Chapter 2: Computer Memory GENERAL INSTRUCTIONS: • Exercises to be written in the book. • Assignment questions to be done in ruled sheets. • You Tube link is for the explanation of Primary and Secondary Memory. YouTube Link: ➢ https://youtu.be/aOgvgHiazQA INTRODUCTION: ➢ Computer can store a large amount of data safely in their memory for future use. ➢ A computer’s memory is measured either in Bits or Bytes. ➢ The memory of a computer is divided into two categories: Primary Memory, Secondary Memory. ➢ There are two types of Primary Memory: ROM and RAM. ➢ Cache Memory is used to store program and instructions that are frequently used. EXPLANATION: Computer Memory: Memory plays a very important role in a computer. It is the basic unit where data and instructions are stored temporarily. Memory usually consists of one or more chips on the mother board, or you can say it consists of electronic components that store instructions waiting to be executed by the processor, data needed by those instructions, and the results of processing the data. Memory Units: Computer memory is measured in bits and bytes. A bit is the smallest unit of information that a computer can process and store. A group of 4 bits is known as nibble, and a group of 8 bits is called byte. -
Chapter 16 Disk Storage, Basic File Structures, Hashing, and Modern Storage
Chapter 16 Disk Storage, Basic File Structures, Hashing, and Modern Storage - Databases are stored as files of records stored on disks - Physical database file structures - Physical levels of three schema architecture 1 - The collection of data in a DB must be stored on some storage medium. The DBMS software can retrieve, update, and process this data as needed - Storage media forms a hierarchy 2 -primary, secondary, tertiary, etc.. - offline storage, archiving databases (larger capacity, less cost, slower access, not directly accessible by CPU) Memory Hierarchies and Storage Devices - Cache, static RAM (Prefetch, Pipeline) - Dynamic RAM (main memory( Secondary and Tertiary Storage -mass storage (magnetic disks, CD, DVD (measured in KB, MB, TB, PB - programs are in main memory (DRAM) -permanent databases reside in secondary storage - main memory buffers are used to read and write to secondary storage - Flash memory: non volatile, NAND and NOR flash based - Optical disks: CDs (700MB) and DVDs (4.5 – 15GB), Blue Ray (54GB) - Magnetic Tapes and Juke Boxes Depending upon the intended use and application requirements, data is kept in one or more levels of hierarchy 3 Storage Organization of Database -Large amount of data that must persist for a long period of time (called persistent data) - parts of this data are accessed and processed repeatedly during the storage period - transient data during the period of execution - most DBs are stored on secondary storage (magnetic disks) - DB is too large to fit in main memory - permanent loss on disk is less likely - less cost on disk than primary storage 4 5 6 - A range of cylinders have the same number of sectors per arc. -
Olympus Optical Disc Archiving Systems & Discstor 900 Optical
Olympus Optical Disc Archiving Systems & DiscStor 900 Optical Disc Storage System Solution Overview All Pro Solutions, Inc. | 1351 E. Black Street, Rock Hill, SC 29730 USA | Tel: +1.803.980.4141 | Web: www.allprosolutions.com | Email: [email protected] The Company – All Pro Solutions, Inc. – Leading manufacturer of automated disc duplicating, printing & publishing systems. – Started in 1996 manufacturing floppy disk duplication systems. – Family-owned and operated. – In South Carolina since 2009. – Provides services like document scanning, imaging, converting. – Expanded into data storage and archiving industry. – Whatever the problem, we find a solution. All Pro Solutions, Inc. | 1351 E. Black Street, Rock Hill, SC 29730 USA | Tel: +1.803.980.4141 | Web: www.allprosolutions.com | Email: [email protected] The Challenge Worldwide Corporate Data Growth Unstructured text Structured data Source: IDC The Digital Universe 2010 80% of Corporate Data is Unstructured File Data Active Less Active Inactive Hot Cold 10% Warm 20% 70% All Pro Solutions, Inc. | 1351 E. Black Street, Rock Hill, SC 29730 USA | Tel: +1.803.980.4141 | Web: www.allprosolutions.com | Email: [email protected] The Solution Blu-Ray Disc – The ideal media for long-term archival • Longevity • Capacity - Extendable • Security • Removability • Data Migration • Accessibility • Compliance • Compatibility • Green Technology • Power Consumption Networked Client Workstations LAN Primary Network Servers All Pro Solutions, Inc. | 1351 E. Black Street, Rock Hill, SC 29730 USA | Tel: +1.803.980.4141 | Web: www.allprosolutions.com | Email: [email protected] The Solution Blu-Ray Disc – The ideal media for long-term archival • Longevity • Capacity - Extendable • Security • Removability • Data Migration • Accessibility • Compliance • Compatibility • Green Technology • Power Consumption Networked Client Workstations Olympus Archiving System LAN DiscStor 900 Storage System Primary Network Servers All Pro Solutions, Inc. -
Secure Data Storage – White Paper Storage Technologies 2008
1 Secure Data Storage – White Paper Storage Technologies 2008 Secure Data Storage - An overview of storage technology - Long time archiving from extensive data supplies requires more then only big storage capacity to be economical. Different requirements need different solutions! A technology comparison repays. Author: Dr. Klaus Engelhardt Dr. K. Engelhardt 2 Secure Data Storage – White Paper Storage Technologies 2008 Secure Data Storage - An overview of storage technology - Author: Dr. Klaus Engelhardt Audit-compliant storage of large amounts of data is a key task in the modern business world. It is a mistake to see this task merely as a matter of storage technology. Instead, companies must take account of essential strategic and economic parameters as well as legal regulations. Often one single technology alone is not sufficient to cover all needs. Thus storage management is seldom a question of one solution verses another, but a combination of solutions to achieve the best possible result. This can frequently be seen in the overly narrow emphasis in many projects on hard disk-based solutions, an approach that is heavily promoted in advertising, and one that imprudently neglects the considerable application benefits of optical storage media (as well as those of tape-based solutions). This overly simplistic perspective has caused many professional users, particularly in the field of long-term archiving, to encounter unnecessary technical difficulties and economic consequences. Even a simple energy efficiency analysis would provide many users with helpful insights. Within the ongoing energy debate there is a simple truth: it is one thing to talk about ‘green IT’, but finding and implementing a solution is a completely different matter. -
Parallel Computer Architecture and Programming CMU / 清华 大学
Lecture 20: Addressing the Memory Wall Parallel Computer Architecture and Programming CMU / 清华⼤学, Summer 2017 CMU / 清华⼤学, Summer 2017 Today’s topic: moving data is costly! Data movement limits performance Data movement has high energy cost Many processors in a parallel computer means… ~ 0.9 pJ for a 32-bit foating-point math op * - higher overall rate of memory requests ~ 5 pJ for a local SRAM (on chip) data access - need for more memory bandwidth to avoid ~ 640 pJ to load 32 bits from LPDDR memory being bandwidth bound Core Core Memory bus Memory Core Core CPU * Source: [Han, ICLR 2016], 45 nm CMOS assumption CMU / 清华⼤学, Summer 2017 Well written programs exploit locality to avoid redundant data transfers between CPU and memory (Key idea: place frequently accessed data in caches/buffers near processor) Core L1 Core L1 L2 Memory Core L1 Core L1 ▪ Modern processors have high-bandwidth (and low latency) access to on-chip local storage - Computations featuring data access locality can reuse data in this storage ▪ Common software optimization technique: reorder computation so that cached data is accessed many times before it is evicted (“blocking”, “loop fusion”, etc.) ▪ Performance-aware programmers go to great effort to improve the cache locality of programs - What are good examples from this class? CMU / 清华⼤学, Summer 2017 Example 1: restructuring loops for locality Program 1 void add(int n, float* A, float* B, float* C) { for (int i=0; i<n; i++) Two loads, one store per math op C[i] = A[i] + B[i]; } (arithmetic intensity = 1/3) void mul(int -
Archiving Online Data to Optical Disk
ARCHIVING ONLINE DATA TO OPTICAL DISK By J. L. Porter, J. L. Kiesler, and D. A. Stedfast U.S. GEOLOGICAL SURVEY Open-File Report 90-575 Reston, Virginia 1990 U.S. DEPARTMENT OF THE INTERIOR MANUEL LUJAN, JR., Secretary U.S. GEOLOGICAL SURVEY Dallas L. Peck, Director For additional information Copies of this report can be write to: purchased from: Chief, Distributed Information System U.S. Geological Survey U.S. Geological Survey Books and Open-File Reports Section Mail Stop 445 Federal Center, Bldg. 810 12201 Sunrise Valley Drive Box 25425 Reston, Virginia 22092 Denver, Colorado 80225 CONTENTS Page Abstract ............................................................. 1 Introduction ......................................................... 2 Types of optical storage ............................................... 2 Storage media costs and alternative media used for data archival. ......... 3 Comparisons of storage media ......................................... 3 Magnetic compared to optical media ............................... 3 Compact disk read-only memory compared to write-once/read many media ................................... 6 Erasable compared to write-once/read many media ................. 7 Paper and microfiche compared to optical media .................... 8 Advantages of write-once/read-many optical storage ..................... 8 Archival procedure and results ........................................ 9 Summary ........................................................... 13 References .......................................................... -
Computer Peripheral Memory System Forecast
OF NBS H^^LK,!,, STAND S. TECH PUBLICATIONS | COMPUTER SUici^CZ^i TECHNOLOGY: COMPUTER PERIPHERAL MEMORY SYSTEM FORECAST QC 100 U57 NBS Special Publication 500-45 #500-45 U.S. DEPARTMENT OF COMMERCE 1979 National Bureau of Standards NATIONAL BUREAU OF STANDARDS The National Bureau of Standards' was established by an act of Congress March 3, 1901 . The Bureau's overall goal is to strengthen and advance the Nation's science and technology and facilitate their effective application for public benefit. To this end, the Bureau conducts research and provides: (1) a basis for the Nation's physical measurement system, (2) scientific and technological services for industry and government, (3) a technical basis for equity in trade, and (4) technical services to promote public safety. The Bureau's technical work is performed by the National Measurement Laboratory, the National Engineering Laboratory, and the Institute for Computer Sciences and Technology. THE NATIONAL MEASUREMENT LABORATORY provides the national system of physical and chemical and materials measurement; coordinates the system with measurement systems of other nations and furnishes essential services leading to accurate and uniform physical and chemical measurement throughout the Nation's scientific community, industry, and commerce; conducts materials research leading to improved methods of measurement, standards, and data on the properties of materials needed by industry, commerce, educational institutions, and Government; provides advisory and research services to other Government Agencies; develops, produces, and distributes Standard Reference Materials; and provides calibration services. The Laboratory consists of the following centers: Absolute Physical Quantities^ — Radiation Research — Thermodynamics and Molecular Science — Analytical Chemistry — Materials Science. -
The Future of Data Storage Technologies
International Technology Research Institute World Technology (WTEC) Division WTEC Panel Report on The Future of Data Storage Technologies Sadik C. Esener (Panel Co-Chair) Mark H. Kryder (Panel Co-Chair) William D. Doyle Marvin Keshner Masud Mansuripur David A. Thompson June 1999 International Technology Research Institute R.D. Shelton, Director Geoffrey M. Holdridge, WTEC Division Director and ITRI Series Editor 4501 North Charles Street Baltimore, Maryland 21210-2699 WTEC Panel on the Future of Data Storage Technologies Sponsored by the National Science Foundation, Defense Advanced Research Projects Agency and National Institute of Standards and Technology of the United States government. Dr. Sadik C. Esener (Co-Chair) Dr. Marvin Keshner Dr. David A. Thompson Prof. of Electrical and Computer Director, Information Storage IBM Fellow Engineering & Material Sciences Laboratory Research Division Dept. of Electrical & Computer Hewlett-Packard Laboratories International Business Machines Engineering 1501 Page Mill Road Corporation University of California, San Diego Palo Alto, CA 94304-1126 Almaden Research Center 9500 Gilman Drive Mail Stop K01/802 La Jolla, CA 92093-0407 Dr. Masud Mansuripur 650 Harry Road Optical Science Center San Jose, CA 95120-6099 Dr. Mark H. Kryder (Co-Chair) University of Arizona Director, Data Storage Systems Center Tucson, AZ 85721 Carnegie Mellon University Roberts Engineering Hall, Rm. 348 Pittsburgh, PA 15213-3890 Dr. William D. Doyle Director, MINT Center University of Alabama Box 870209 Tuscaloosa, AL 35487-0209 INTERNATIONAL TECHNOLOGY RESEARCH INSTITUTE World Technology (WTEC) Division WTEC at Loyola College (previously known as the Japanese Technology Evaluation Center, JTEC) provides assessments of foreign research and development in selected technologies under a cooperative agreement with the National Science Foundation (NSF). -
3 Secondary Storage.PDF
CAPE COMPUTER SCIENCE SECONDARY STORAGE Secondary storage is needed 1. because there is a limit on the size of primary memory (due to cost) and 2. because RAM is volatile and so data needed for future use must be stored somewhere else so that it can be retrieved when necessary. Secondary storage is also used for backup and archives. When we consider secondary storage devices we must bear in mind the following characteristics of each device : Capacity Access speed Access method and portability Floppy Disk This is a 3.5 inch magnetic disk of flexible material which until recently was a standard feature on most microcomputers. Typically it stores 1.44 MB of data. It’s a thin plastic circle coated with a magnetic material and encased in a rigid plastic to protect it. A metal sliding access shuttle opens when the disk is in the machine allowing the read/write head access to the disk. Data can be written to and erased from a floppy disk. A write protect tab can be used to prevent accidental overwriting of data. Before data can be written to a disk, it must be formatted. This prepares the disk for use by creating a magnetic map on the disks surface. This map consists of tracks and sectors. Formatting also prepares the file allocation table (FAT). The address of a file on a floppy disk is comprised of the track number and the sector number. Floppy disks are direct access devices but they are slow compared to hard disks. The floppies great advantage has been its use as a device to help transport small files between machines.