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Addresses of virtual memory is found in descriptor table lies in primary memory but the content of the page is stored in secondary memory.
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Which early theorist kept a baby biography of his children's development?
charles darwin
How does Albert Einstein prevent his mental illness?
He kept a track of himself of highly sensitiveawareness.
What are Houdini's personality traits?
he is nice and kind because when he made $12 he gave $10 to his mom and only kept $2 for himself
What does a psychrometer use?
It is an instrument for determining atmospheric humidity by the reading of two thermometers, one bulb being kept moist and ventilated
This guy was laying on the floor in class with his legs spread apart and kept looking at me and moving closer while i was in my desk Does he like me?
He doesn't like you. He 'wants' you.
What is storage in computer science?
storage refers to the keeping of data and information for later. in computer science there are two types of storage that is primary storage and secondary storage in primary storage data is kept temporary in ROM(read only memory) while in secondary storage data is kept permanently like on hard disk, tape, cds.
Distinguish between primary storage and secondary storage?
Primary storage, also known as main memory or internal memory, refers to the storage space in a computer that is directly accessible to the processor. Primary storage is typically used to store data and instructions that are currently being used or processed by the computer. Secondary storage, also known as external memory, refers to storage space that is not directly accessible to the processor, but is used to store data and instructions for longer periods of time. Secondary storage is typically used to store data that is not currently being used, but that needs to be kept for future reference. There are several key differences between primary storage and secondary storage: Speed: Primary storage is generally faster than secondary storage, as it is directly accessible to the processor. This means that the processor can access and retrieve data from primary storage more quickly than it can from secondary storage. Capacity: Primary storage is typically smaller in capacity than secondary storage. This is because primary storage is used to store data that is currently being used or processed, while secondary storage is used to store data that is not currently being used. Cost: Primary storage is typically more expensive than secondary storage, as it requires faster and more expensive memory chips. Volatility: Primary storage is generally volatile, meaning that it is lost when the power is turned off. In contrast, secondary storage is non-volatile, meaning that it retains data even when the power is turned off. Location: Primary storage is located inside the computer, while secondary storage is typically external to the computer and is connected to the computer through a port or interface.
What are the different types of memory modules?
The processor uses temporary storage, called primary storage or memory, to temporarly hold both data and instructions while it is processingthem. Pimary storage is much faster to access than permanent storage. however, when data and instructions are not being used, they must be kept in permanent storage sometimes called secondary storage, such as a hard drive, CD or floppy .
Where is Virtual memory kept?
Virtual Memory is kept in a RAM chip inside a computer and is described as "volatile" i.e it will disappear when a computer is switched off, you also will find it inside graphics cards (the more it has, the more complex graphics it can process.) Many windows and some Unix systems also use a small portion of the hard drive as virtual memory, though you can set limits on this or remove it entirely.
When data and instructions are not being used they must be kept in permanent storage sometimes called?
Permanent or Secondary storage - such as a hard drive, CD, DVD, or USB drive
Write detail note on secondary storage devices?
Secondary storage (also known as external memory or auxiliary storage), differs from primary storage in that it is not directly accessible by the CPU. The computer usually uses its input/output channels to access secondary storage and transfers the desired data using intermediate area in primary storage. Secondary storage does not lose the data when the device is powered down---it is non-volatile. Per unit, it is typically also two orders of magnitude less expensive than primary storage. Consequently, modern computer systems typically have two orders of magnitude more secondary storage than primary storage and data are kept for a longer time there. In modern computers, hard disk drives are usually used as secondary storage. The time taken to access a given byte of information stored on a hard disk is typically a few thousandths of a second, or milliseconds. By contrast, the time taken to access a given byte of information stored in random access memory is measured in billionths of a second, or nanoseconds. This illustrates the significant access-time difference which distinguishes solid-state memory from rotating magnetic storage devices: hard disks are typically about a million times slower than memory. Rotating optical storage devices, such as CD and DVD drives, have even longer access times. With disk drives, once the disk read/write head reaches the proper placement and the data of interest rotates under it, subsequent data on the track are very fast to access. As a result, in order to hide the initial seek time and rotational latency, data are transferred to and from disks in large contiguous blocks.When data reside on disk, block access to hide latency offers a ray of hope in designing efficient external memory algorithms. Sequential or block access on disks is orders of magnitude faster than random access, and many sophisticated paradigms have been developed to design efficient algorithms based upon sequential and block access. Another way to reduce the I/O bottleneck is to use multiple disks in parallel in order to increase the bandwidth between primary and secondary memory.[3]Some other examples of secondary storage technologies are: flash memory (e.g. USB flash drives or keys), floppy disks, magnetic tape, paper tape, punched cards, standalone RAM disks, and Iomega Zip drives.The secondary storage is often formatted according to a file system format, which provides the abstraction necessary to organize data into files and directories, providing also additional information (called metadata) describing the owner of a certain file, the access time, the access permissions, and other information.Most computer operating systems use the concept of virtual memory, allowing utilization of more primary storage capacity than is physically available in the system. As the primary memory fills up, the system moves the least-used chunks (pages) to secondary storage devices (to a swap file or page file), retrieving them later when they are needed. As more of these retrievals from slower secondary storage are necessary, the more the overall system performance is degraded.
Describe different types of primary and secondary memory of a computer?
Primary memory is that which is directly connected to the motherboard for the CPU to process, meaning your RAM modules. Secondary memory is located on the hard drive in a virtual memory (called a page file or swap file) when the RAM modules have no more room to store data that is still running, but still needs to recall some as soon as it can swap out what processes have the higher priority. When the RAM and page file are full, you will notice a lag in computer performance as it struggles to process so much data at one time. If it exceeds the limits of your memory and processor, the system may crash. A fixed large swap file and more memory makes the CPU work less and a better, faster CPU will keep the memory demands lower. This is why more memory and a faster CPU is needed for more complex data processing. To reduce processing even further, a dedicated graphics card with it's own memory and built in CPU that handles the graphic processing allows for the RAM and CPU to work much less, making the computer much more faster.
What is meant by primary storage?
Primary storage, also known as main storage or memory , is the main area in a computer in which data is stored for quick access by the computer's processor . On today's smaller computers, especially personal computers and workstations, the term random access memory (RAM ) - or just memory - is used instead of primary or main storage, and the hard disk, diskette, CD, and DVD collectively describe secondary storage or auxiliary storage.The terms main storage and auxiliary storageoriginated in the days of the mainframe computer to distinguish the more immediately accessible data storage from storage that required input/output operations. An earlier term for main storage was core in the days when the main data storage contained ferrite cores.2) Primary storage is sometimes used to mean storage for data that is in active use in contrast to storage that is used for backup purposes. In this usage, primary storage is mainly the secondary storage referred to in meaning 1. (It should be noted that, although these two meanings conflict, the appropriate meaning is usually apparent from the context.)
What is the need of computer memory?
Although memory is technically any form of electronic storage, it is used most often to identify fast, temporary forms of storage. If your computer's CPU had to constantly access the to retrieve every piece of data it needs, it would operate very slowly. When the information is kept in memory, the CPU can access it much more quickly. Most forms of memory are intended to store data temporarily.
What is the primary and secondary?
Primary storage refers to onboard computer memory or Random Access Memory (RAM). It is memory that can be accessed directly by the CPU hardware using a memory address to fetch and process instructions and data. It is where computer programs are held while being executed. It is where data is held while it is being processed by computer instructions computer programs are held while being executed.Computer memory includes, Computer memory includes:Volatile RAM is semiconductor memory that loses its information when power is lost or the computer is turned off.Static RAM is volatile memory that does not lose its information when the computer is turned off or loses power.Read Only Memory (ROM) is memory that has fixed information prerecorded or preset and can not be changed. ROM contains the program that is first run when a computer is turned on. On a PC it is the program that runs before control is transferred to the BIOS. It may be a semiconductor chip that can only be modified once or it can be the actual arrangement of the circuitry on a chip.Programmable Read Only Memory (PROM) is a Read Only Memory that can be changed under special circumstances. Depending on the type of PROM, you may need special equipment, or need to use special instructions to write to this kind of memory. AN example is the BIOS program on a personal computer that needs a special "flash" process to update the version of BIOS it is using.Secondary storage is the media that hold your programs and data, other than when it is being used in memory.It is normally a hard drive or disk drive (magnetic media or solid state) that is kept as part of your computer system.Disk drives are also used for off site or backup storage. They are normally mounted in protective cases and connect to the computer with a USB, Firewire, or other proprietary connection.Secondary storage also includes other media such as floppy disks, diskettes, tape on reels or in cartridges, optical media (CD, DVD) or removable solid state media (referred to as flash drives, USB drives, memory sticks, SD cards, etc.It is used to save, backup, protect and transport information from one location to another.There is an alternate opinion that the hard drive should be considered primary storage and other removable storage device should be considered secondary storage.----------Primary storage, also known as main storage is the location where most of your data is stored on your computer. EXAMPLE.... HARD diskSecondary storage, some times called auxiliary storage is used to take care of the limitation of primary storage. EXAMPLE.... CD(compect disk),DVD(digital vedio disk),SD card,Memory card e.t.c----------Primary storage in a computer: RAM or random access memory is the first stage of memory (primary), it holds things such as your operating system in the ram memory so as you boot your computer it grabs it from ram, as it would be faster than accessing your hard drive every time you boot.Secondary storage is your Hard drive, where you save information on which is accessed via your operating system.is CD a primary or a secondary storage device----------Primary storage is RAM (Random Access Memory) and cache.Secondary storage is Floppy, hard drive, CDs.The primary form of storage is the hard drive that is the default also. You can also save onto flash drives, floppies, and cds which are examples of secondary forms of storage
How are primary and secondary storage alike and different?
Primary storage (or main memory or internal memory), often referred to simply as memory, is the only one directly accessible to the CPU. The CPU continuously reads instructions stored there and executes them as required. Any data actively operated on is also stored there in uniform manner.Historically, early computers used delay lines, Williams tubes, or rotating magnetic drums as primary storage. By 1954, those unreliable methods were mostly replaced by magnetic core memory, which was still rather cumbersome. Undoubtedly, a revolution was started with the invention of a transistor, that soon enabled then-unbelievable miniaturization of electronic memory via solid-state silicon chip technology.This led to a modern random-access memory (RAM). It is small-sized, light, but quite expensive at the same time. (The particular types of RAM used for primary storage are also volatile, i.e. they lose the information when not powered).As shown in the diagram, traditionally there are two more sub-layers of the primary storage, besides main large-capacity RAM:Processor registers are located inside the processor. Each register typically holds a word of data (often 32 or 64 bits). CPU instructions instruct the arithmetic and logic unit to perform various calculations or other operations on this data (or with the help of it). Registers are technically among the fastest of all forms of computer data storage.Processor cache is an intermediate stage between ultra-fast registers and much slower main memory. It's introduced solely to increase performance of the computer. Most actively used information in the main memory is just duplicated in the cache memory, which is faster, but of much lesser capacity. On the other hand it is much slower, but much larger than processor registers. Multi-level hierarchical cache setup is also commonly used-primary cache being smallest, fastest and located inside the processor; secondary cache being somewhat larger and slower.Main memory is directly or indirectly connected to the CPU via a memory bus. It is actually two buses (not on the diagram): an address bus and a data bus. The CPU firstly sends a number through an address bus, a number called memory address, that indicates the desired location of data. Then it reads or writes the data itself using the data bus. Additionally, a memory management unit (MMU) is a small device between CPU and RAM recalculating the actual memory address, for example to provide an abstraction of virtual memory or other tasks.As the RAM types used for primary storage are volatile (cleared at start up), a computer containing only such storage would not have a source to read instructions from, in order to start the computer. Hence, non-volatile primary storage containing a small startup program (BIOS) is used to bootstrap the computer, that is, to read a larger program from non-volatile secondary storage to RAM and start to execute it. A non-volatile technology used for this purpose is called ROM, for read-only memory (the terminology may be somewhat confusing as most ROM types are also capable of random access).Many types of "ROM" are not literally read only, as updates are possible; however it is slow and memory must be erased in large portions before it can be re-written. Some embedded systems run programs directly from ROM (or similar), because such programs are rarely changed. Standard computers do not store non-rudimentary programs in ROM, rather use large capacities of secondary storage, which is non-volatile as well, and not as costly.Secondary storage (or external memory) differs from primary storage in that it is not directly accessible by the CPU. The computer usually uses its input/output channels to access secondary storage and transfers the desired data using intermediate area in primary storage. Secondary storage does not lose the data when the device is powered down-it is non-volatile. Per unit, it is typically also an order of magnitude less expensive than primary storage. Consequently, modern computer systems typically have an order of magnitude more secondary storage than primary storage and data is kept for a longer time there.In modern computers, hard disk drives are usually used as secondary storage. The time taken to access a given byte of information stored on a hard disk is typically a few thousandths of a second, or milliseconds. By contrast, the time taken to access a given byte of information stored in random access memory is measured in billionths of a second, or nanoseconds. This illustrates the very significant access-time difference which distinguishes solid-state memory from rotating magnetic storage devices: hard disks are typically about a million times slower than memory. Rotating optical storage devices, such as CD and DVD drives, have even longer access times. With disk drives, once the disk read/write head reaches the proper placement and the data of interest rotates under it, subsequent data on the track are very fast to access. As a result, in order to hide the initial seek time and rotational latency, data are transferred to and from disks in large contiguous blocks.When data reside on disk, block access to hide latency offers a ray of hope in designing efficient external memory algorithms. Sequential or block access on disks is orders of magnitude faster than random access, and many sophisticated paradigms have been developed to design efficient algorithms based upon sequential and block access . Another way to reduce the I/O bottleneck is to use multiple disks in parallel in order to increase the bandwidth between primary and secondary memory.[2]Some other examples of secondary storage technologies are: flash memory (e.g. USB flash drives or keys), floppy disks, magnetic tape, paper tape, punched cards, standalone RAM disks, and Iomega Zip drives.The secondary storage is often formatted according to a file system format, which provides the abstraction necessary to organize data into files and directories, providing also additional information (called metadata) describing the owner of a certain file, the access time, the access permissions, and other information.Most computer operating systems use the concept of virtual memory, allowing utilization of more primary storage capacity than is physically available in the system. As the primary memory fills up, the system moves the least-used chunks (pages) to secondary storage devices (to a swap file or page file), retrieving them later when they are needed. As more of these retrievals from slower secondary storage are necessary, the more the overall system performance is degraded.
What is the advantage of using a CPU register for temporary data storage over using a memory location?
Simple answer - speed. By using the CPU register, the information is kept "local" to the CPU. By storing a value in a memory location, a lookup has to be performed to retrieve it.
