The earliest storage devices were punched paper cards, which were used as early as 1804 to control silkweaving looms. Magnetic tape was early secondary storage medium relatively permanent and holds large quantities of data access time slow random access times slower than disk mainly used for backup, storage of infrequentlyused data, transfer. Universal serial bus mass storage specification for bootability. Use of the material is authorized for personal use, and for use in conjunction with a course for which operating system concepts is the prescribed text. Disk structure n disk drives are addressed as large 1dimensional arrays of logical blocks, where the logical block is the smallest unit of transfer. The data is arranged within a file in blocks, and the position. Disks are small and cheap, so its easy to put lots of disks in one box for increased storage, performance, and availability. Mass chapter9 storage structure practice exercises 9. Secondary storage includes memory devices that are. Data on a harddrive is often arranged into files by the operating system. In order to use mass storage, the mode must first be. Mass storage structure this covers a retired java programming problem.
Magnetic disks provide the bulk of secondary storage for modern computer systems. In this section we present a general overview of the physical structure of secondary and tertiary storage devices. Conceptually, disks are relatively simple figure 12. Mass storage mode is a feature on android smartphones and blackberrys that enables devices as a removable drive when connected to a computer. And tertiary storage refers to removable media, such as tape drives, cds, dvds, and to a lesser extend floppies, thumb drives, and other detachable devices. To describe the physical structure of secondary storage devices and its effects on the uses of the devices to explain the performance characteristics of mass storage devices to evaluate disk scheduling algorithms to discuss operatingsystem services provided for mass storage, including raid. Apr 20, 2009 overview of mass storage structure disk structure disk attachment disk scheduling disk management swapspace management raid structure disk attachment stables slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. In this chapter, we begin a discussion of file systems at the lowest level. Solid state disks have the same characteristics as traditional hard disks. This storage is typically very small, ultrafast, and volatile. Abraham silberschatz, greg gagne, and peter baer galvin, operating system concepts, eighth edition, chapter 12 12. Overview of mass storage structure surendar chandra. To explain the performance characteristics of mass storage devices to evaluate disk scheduling algorithms to discuss operatingsystem services provided for mass storage, including raid 12. To describe the physical structure of secondary storage devices and its effects on the uses of the devices.
In particular, design separate classes that implement the following scheduling algorithms. The choice of file system is often important in maximizing the performance of the device. Data plus some redundant information is striped across the disks in some way. In chapter 11, we examine the user and programmer interface to the file system. It is a comprehensive computer storage system that is usually very slow, so it is usually used. Massstorage structure this covers a retired java programming problem. Mar 07, 2017 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 operatingsystem services provided for mass storage, including raid and hsm 4. Particular devices, such as hddsandnvm devices, are specifiedasappropriate.
Start studying operating systems 3 chapter 12 mass storage structure. Chapter 10 massstorage structure operating system concepts. Mass storage systems adapted from textbook slides figure 11. Io systems 8 disk attachment storagearea network common in large storage environments and becoming more common multiple hosts attached to multiple storage arrays flexible massstorage structure. Secondary storage devices are used to store data for future use or as backup. Hence, knowing the structure of a magnetic disk is necessary to understand how the data in the disk is accessed by the computer. Bulk of secondary storage for modern computers is hard disk drives. Overview of mass storage structure magnetic disks provide bulk of secondary storage of modern computers zdrives rotate at 60 to 200 times per second ztransfer rate is rate at which data flow between drive and computer zpositioning time randomaccess time is time to move disk arm to desired.
Massstorage structure inthischapter, we discusshow massstoragethe nonvolatile storagesys. It is a comprehensive computer storage system that is usually very slow, so it is usually used to archive data that is not accessed frequently. Modern mass storage devices include all types of disk drives and tape drives. Nonbuilding structures comprise a myriad of structures constructed of all types of materials with markedly different dynamic characteristics and a wide range of performance requirements. How does the physical design of storage devices affect the software design and performance of the os. Slides are from the book authors, modified and selected by jean mayo, shuai wang and ck shene. Marvin minsky throughout the course we will use overheads that were adapted from those distributed from the textbook website. Magnetic tape was early secondary storage medium relatively permanent and holds large quantities of data access time slow random access times slower than disk mainly used for backup, storage of infrequentlyused data, transfer medium between systems. Freeplacement administration complex objects memorybased record addressing mapping of. Mass storage devices used in desktop and most server computers typically have their data organized in a file system. Cmos silicon structure and high speed, low power consumption.
A mass storage device msd is any storage device that makes it possible to store and port large amounts of data across computers, servers and within an it environment. Requests generally arrive from a single process for one block or for a sequence of. Overview of mass storage structure magnetic disks provide bulk of secondary storage drives rotate at 70 to 250 times per second ipod disks. Hard disk platters are made of rigid metal, while floppy disks are made of more flexible plastic. To use a disk to hold files, the operating system still needs to record its own data structures on the. Overview of mass storage structure cont magnetic tape zwas early secondary storage medium zrelatively permanent and holds large quantities of data zaccess time slow zrandom access times slower than disk zmainly used for backup, storage of infrequentlyused data, transfer medium between systems. Price per megabyte of dram, from 1981 to 2004 mass storage structure price per megabyte of hard disk, from 1981 to 2004 is it only about price where. How does the os provide access to storage resources. Despite the different technologies, theres tremendous commonality as. In modern computers, most of the secondary storage is in the form of magnetic disks.
Msds are portable storage media that provide a storage interface that can be both internal and external to the computer. Mass storage structure spring 2019 you dont understand anything until you learn it more than one way. Fsector 0 is the first sector of the first track on the outermost cylinder. Hostattached storage communication techniques ide, ata. In chapter 10, we examine the user and programmer interface to the. The file system can be viewed logically as consisting of three parts. A usb device interface to enable the device to communicate with a pc or other usb host. Storage to maintain the quality of grain after harvest for maintaining the supply of grain taking advantage of higher prices two methods of grain storage bag storage loose in bulk storage the choice based on the local factors type of grain duration of.
Operating system concepts essentials 8th edition 11. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Overview of mass storage structure magnetic disks provide bulk of secondary storage of modern computers drives rotate at 60 to 250 times per second transfer rate is rate at which data. Mass storage is distinct from memory, which refers to temporary storage areas within the computer. Io systems 11 raid raid 10 becoming more and more popular. Operating system notes pdf os pdf notes free sw 2020. Storage devices tertiary storage typically it involves a robotic mechanism which will mount insert and dismount removable mass storage media into a storage device. 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. Every usb massstorage device must support two interfaces.
The information can be anything that can be stored electronically. Chapter 12 mass storage structure operating system. Mass storage disk drives and solidstate drives store the operating system and applications. Traditional magnetic disks have the following basic structure. Mass chapter12 storage structure practice exercises 12. Universal serial bus mass storage specification for bootability revision 1. Secondary storage refers to fixeddisk storage systems hard drives. In chapter 12, we describe the internal data structures and algorithms used by the operating system to implement this interface. Objectives describe the physical structure of secondary and tertiary storage devices and the resulting effects on the uses of the devicesand the resulting effects on the uses of the devices explain the performance characteristics of mass storage devices discuss operatingsystem services provided for mass storage, including raid and hsm operating system concepts 8 th edition 12. Raid structure a raid is a redundant array of independent disks. Designing and programming a usb massstorage device or embedded usb host involves a variety of interfaces, protocols, and structures. Massstorage systems overview of mass storage structure disk structure disk attachment disk scheduling disk management swapspace management raid structure stable storage implementation operating system concepts 10th edition 11. Nonbuilding structure design 3 chapter 15 of the standard is devoted to nonbuilding structures.
In a singleuser environment, the io queue usually is empty. Chapter 10 massstorage structure flashcards quizlet. Pdf mass storage structure shivashekharayya viraktamath. Mass storage systems n disk structure n disk scheduling n disk management n swapspace management n raid structure n disk attachment n stable storage implementation n tertiary storage devices n operating system issues n performance issues. Structure in this section we present a general overview of the physical structure of secondary and tertiary storage devices. A computers hard drive is a massstorage device, as are flash, cd, and dvd drives. Secondary storage and disk scheduling algorithms studytonight.