The Virtual Memory Manager (Vmm)

In: Computers and Technology

Submitted By kingsmich
Words 1372
Pages 6
The Virtual Memory Manager (VMM)
The Difference between virtual memory and physical memory Physical memories are the RAM chips purchased and placed in a slot on the computer motherboard. The RAM is the first memory used when the computer requires memory usage, such as for loading an application or opening a document.
 Virtual
Virtual memory is stored on the hard drive. Virtual memory is used when the RAM is filled. Virtual memory is slower than physical memory, so it can decrease the performance of applications.
 Allocation
Physical memory allocates information in a "first in, last out" process. The information is placed on the stack. Virtual memory uses a process called paging. These pages are laid across the hard drive in fixed sizes.
 Size
1. Physical memory is limited to the size of the RAM chips installed in the computer. Virtual memory is limited by the size of the hard drive, so virtual memory has the capability for more STORAGE.
2. Virtual memory is a memory management technique developed for multitasking kernels.
3. In virtual memory Operating systems have memory areas that are pinned (never swapped to secondary storage). For example, interrupt mechanisms rely on an array of pointers to their handlers, such as I/O completion and page fault. If the pages containing these pointers or the code that they invoke were pageable, interrupt-handling would become far more complex and time-consuming, particularly in the case of page fault interruptions. Hence, some part of the page table structures is not pageable (SPECTORA).
1) Physical Memory is the actual memory chips inside your computer. It's a very fast type of memory that the computer can access very quickly and efficiently.

2) Virtual Memory is a space on your hard drive. The computer uses this from time to time instead of using the physical memory. As this is space on the hard…...

Similar Documents

Virtual Memory

...head: THE BENEFITS AND USES OF VIRTUAL MEMORY The Use and Benefits of Virtual Memory Jacqueline Askew University of Phoenix Abstract There are many computer users that are not familiar with computers or the way they function. This paper is centered around and will provide a definition of virtual memory. Information will also be provided on the benefits and how virtual memory used. The Use and Benefits of Virtual Memory There are so many facets to computers and how they function. Someone that is a novice user is not aware of how they run. They just turn them on and ready, set go. The more advanced computer user has a better insight to the functionality and maintenance of the computer. Whether it is a laptop or desktop the most common part of an operating system is virtual memory. Based on how much memory a computer has determines how many programs can be run. Virtual memory uses free space found on the hard drive in order to allow other programs to run. This seamless transition is unnoticeable to the human eye. Because the virtual memory frees up space in the Random Access Memory, other applications can load. This is an automatic process, so even with the standard memory virtual memory makes it seems like it has more. One of the benefits of virtual memory is the financial side. There is not a lot of out of pocket expense because it becomes more expensive to purchase RAM chips than hard disk space. The virtual memory will allow a user to run......

Words: 472 - Pages: 2

The Benefits and Uses of Virtual Memory

...The Benefits and Uses of Virtual Memory Marcia Amnay POS/355 Steven Kernan April 22nd, 2013 The Benefits and Uses of Virtual Memory This paper will discuss the benefits and uses of virtual memory. Programs require memory to start and run on computers. When several jobs are being processed at the same time, the operating system must keep track of how the computer’s memory and make sure there is enough. Computers come with a limited amount of random access memory which is known as RAM. RAM is the main memory on a computer. If a user is running multiple applications at the same time, the RAM on it will not be enough to execute the processes. This is when virtual memory comes in and balances the process. Virtual memory is a memory management technique. Virtual memory is secondary memory that can act as if it were part of the main memory. When the RAM is used up, virtual memory places data by using the hard disk or another disk of some kind for space. The hard disk is much slower then RAM so the more virtual memory used, the slower your computer will run. The computer will look for areas on the RAM that are not in use and copy it to the hard disk to free up space on the RAM. Virtual memory keeps ‘active’ process in the RAM and keeps the ‘inactive’ processes on the address space on the disk. When an ‘inactive’ process is needed, it will bring that process back to the RAM from the disk. This process is running in the background without the user being......

Words: 788 - Pages: 4

Memory Management

...Memory Management Federico Torres POS 355 April 9, 2013 CASTLE W. PHELPS, ABD Memory Management “I cannot guarantee that I carry all the facts in my mind. Intense mental concentration has a curious way of blotting out what has passed. Each of my cases displaces the last…”(Doyle, 1901). The way the brain manages memory is metaphorically speaking very similar to the way computers today manage memory. A memory management unit takes a huge part in the speed at which computers can operate. The memory management unit works systematically with the operating system and computer processing unit. There are two different parts to types of memory, primary, also referred to as main, and secondary. The former has two parts, one part for the kernel, which is reserved for the operating system, and the other part for the programs currently being executed. Memory management units must work efficiently in transferring information between primary and secondary. In order for this to succeed, there are a few requirements that memory management units must meet in order to fulfill the demands of users. Memory management units require relocation, protection, sharing, both local and physical organization, among processes in both primary and secondary memory. Two examples of operating systems that meet these requirements, but yet both manage memory differently are Windows and OS X, which is used by Macintosh as an operating system. Since main memory is shared among different types of......

Words: 2327 - Pages: 10

Virtual Memory

...There are many benefits of using virtual memory; the most important part is memory management, Memory management is the process of managing computer memory. The memory management subsystem of the operating system carries out this duty. Because the beginning of calculating, there has always existed the need for more memory than the existing physical memory in the system. Surrounded by many important jobs an operating system does in a computer memory allocation to the processes being implemented is the most important one. Operating systems should have the capability to assign memory when available and clear to make room for data and instructions when the memory is full. The capability to recognize the location of an entire program or a particular location in the physical memory is another responsibility the operating system should be able to accommodate. Operating systems are designed to take benefit of file system conveniences and virtual memory to address the needs of memory management. Data stored in long-term memory is saved as named objects called files, and data and instructions stored in virtual memory is addressed in a logical point of view. Because of the small ability of the virtual memory, only a limited part of a program is kept in virtual memory. The ability to address memory both reasonably and physically enables the operating system to separate processes and run several programs run concomitantly. By using virtual addresses and real addresses, the......

Words: 336 - Pages: 2

Memory Management

...Memory Management March 7, 2014 Memory Management Memory is one of the basic elements on a computer system. The memory allows the user to store data and programs. Memory management is the controlling, coordination and management of the computer memory (). The different memory types a computer has are a cache, main memory, and a disk used for virtual memory. Managing this memory will allow the user to access information faster. The memory management system is on the most important parts in the operating system. In this essay will be discussing the differences in memory management between Windows and Linux base operating system. Windows has implemented several technologies, for both resource allocation and security("Windows Memory Management", 2008). One of these technologies is Dynamic Allocation Space Layout Randomization, which all dynamically adjusts according to operation requirements. Windows uses virtual address space to make that could be bigger or smaller than the physical memory on the computer. Windows memory manager has two first-in-rank responsibilities("Windows Memory Management", 2008). The first is to translate, or map, a process’s virtual address space into physical memory so that when a thread is running in the context of that process reads or writes to the virtual address space, the correct physical address is referenced ("Windows Memory Management", 2008). This minimizes hackers’ threats to the computer system. Second on is paging some of......

Words: 616 - Pages: 3

Memory Management

...Memory Management: Memory management operations are one of the fundamental core components of an operating system. The memory management function is to organize and manage memory hierarchy of the random access memory, bulky address spaces, memory mapping, manage alternate memory devices, physical allocation, de-allocation of processes, and the computer’s hard drive. Physical address is the address perceived by the memory unit. Virtual memory is the necessity of memory by exploiting the hard drive as additional access memory. What is Memory: An exceptional concept of virtual memory is to present a software application program with the appearance of additional or a considerable amount of memory accessible for its programming use. The virtual memory management system will require mapping functions, which execute address translations converting virtual addresses to physical addresses. The virtual or logical address is the address used to communicate a memory location and physical address is the actual memory location passed to the local memory bus. Paging: In paging, the local address space for both virtual and physical memory is divided into fixed size blocks called pages. The pages can be individually located at different areas in the hard drive and physical memory. The address translation is carried out by the memory management system of the central processing unit. Compare/Contrast: Windows: When running, Windows can access up to four gigabytes of physical......

Words: 843 - Pages: 4

Virtual Computing

...Virtual Computing: How is it Used? What are the benefits? Virtual Computing: What is it? What are the Benefits? Introduction Partitioning or dividing the resources of a single server into multiple segregated VMs is virtualization. Virtual computing allows organizations to save technical resources and money. There are various virtual computing applications which are useful to organizations. The benefits of virtual computing are achieving faster system speeds, eliminating upfront capital costs, managing corporate desktops in an efficient way and allowing reduction in power costs. Main VMs were originally in use by IBM around 1960 and were intended to leverage investments in pricy mainframe computers. “Virtualization, or technology that allows one physical PC or server to act like many separate computers, is just one of many strains on traditional software licensing. In the old days, things were simple: Each program ran once on a computer that had a single user and a single processor. Now, it is not uncommon for a program or operating system to be running multiple times on the same piece of hardware, which may be powered by multiple processors, or a single chip with multiple processing cores.” (Fried, 2006) With virtual computing allows users remote access to software applications and processes whenever it is needed. Access is gained through the internet, wireless network or network server. Through virtual computing providers, users can download and use more than......

Words: 1402 - Pages: 6

Memory Management

...Memory Management Vicki Zafke POS/355 June 02, 2014 Melba Beavers Memory Management A critically important component of a computer’s operating system is the memory. Memory management is the act of monitoring and handling the memory. An operating systems memory management includes tasks such as relocation, protection, sharing, and organization. Although there are several basic factors in regards to memory management, some operating systems have distinguishing features that set them apart from one another. There are two main tasks that an operating system must achieve during the memory management cycle. Each process has its own memory space. For example, in the 32-bit Windows operating system each process is allotted up to 4 gigabytes of memory in the virtual address space. The first task is to ensure that the process does not run into another processes space and that another process does not run into it. The second task is in order for the process to run effectively, the different types of memory must be used properly. Virtual memory is a common concept for operating systems. “The Windows virtual memory manager controls how memory is allocated and how paging is performed.”(Stallings, 2012, p. 386). Virtual memory is separated into two parts, one for the process and one for the system. For example, the 4 gigabytes in the 32-bit Windows operating system is divided into two so that 2 gigabytes is reserved for the process and 2 gigabytes is reserved for the......

Words: 448 - Pages: 2

Memory Management

...Comparison Paper. Memory management is the act of managing computer memory. The essential requirement of memory management is to provide ways to dynamically allocate portions of memory to programs at their request, and free it for reuse when no longer needed. The memory management system is one of the important parts of the operating system. Its basic function is to manage the memory hierarchy of RAM and secondary memory devices. There is always a need of more memory than physical memory. Memory management allows this to be done through the concept of virtual memory. Virtual memory can be many times larger than the physical memory. The most important task of memory management includes allocation and dealloacation of memory to the processes running on the system. Other requirements of memory management are relocation, protection, sharing, logical organization, and physical organization Relocation Stallings states, when an active process is swapped out of main memory to disk it would be quite limiting to specify that when it is next swapped back in, it must be placed in the same main memory region as before. Instead, we may need to relocate the process to a different area of memory (Stallings, 2015). Protection The main purpose of memory protection is to prevent a process from accessing memory that has not been allocated to it. This prevents a bug within a process from affecting other processes, or the operating system itself. Sharing Shared memory......

Words: 1317 - Pages: 6

Memory Management

...Memory Management Paper Gene Cotton POS/355 Terance Carlson 10/06/2014 The act of managing computer memory is known as memory management. This system is also known for allocating memory for certain programs as requested. Managing the memory properly is vital to any CPU system. If the there isn’t enough memory to run a program or application then the CPU may freeze or fail. There are two types of memory allocations systems that are commonly used Virtual Memory and Garbage Collection. Virtual Memory systems separate memory from physical addresses to distinguish between the amounts of RAM used efficiently through disk swapping. Basically the quality of the virtual manager can positively or negatively impact the overall CPU performance. The Garbage collection system is a distribution and or redistribution of the computer memory cores for a program or application. Usually this is maintained and managed at the programming level. The downside to Garbage collection is it may take up a large amount of total processing time and this also can affect the outcome of CPU performance. With memory management systems on multi-tasking operating systems the virtual memory programs must be able to be launched from different parts of the memory at any given time. So relocation is very important and is a requirement. The reason behind this is that when a program is closed or swapped back into memory it may not always be transitioned back to same place it came from. Most virtual......

Words: 400 - Pages: 2

Virtual Memory

...Peoples had great expectations on windows mobile after the release of its first preview of mobile OS. Microsoft seems to be lost in mobile market today because lack of customizability, limited multitasking, device compatibility and so on. Certainly the idea behind one size fits all is to remove the big difference between ARM based PC and x86 or x64 based PC. Right now I see most disagreements over web on Microsoft’s new design which shows persuade of creating single platform for all type of hardwires like PDAs, Laptops, Palmtops, Desktops etc. But I think it’s a good idea to bring up in order to lead mobile market. Apple is already in a run to merge Mac OS and IOS together, to some extend that bought an extra ordinary feature for the organization to role the market. On the other hand companies like Google (Android), Canonical (Ubuntu) are also showing their efforts in bringing their products into a single universal OS. Mobiles are not less than a PC these days. An ARM based OSs like Debian, Android, Chrome OS, Firefox OS, Kali Linux are just the best examples running on PCs and PDAs. Although there can be some issues with the hardware and application support I do agree but someone (so why not Microsoft?) has to take a first step to lead and eventually that will be fruitful outcomes thereafter. But if this idea hits then developers need not to worry about writing same applications in multiple languages, overall it will be cost effective and so on. ......

Words: 351 - Pages: 2

Virtual Memory

...What are some differences from the new version that make creation and deployments of VMs easier (or better)? The essential contrasts are STANDARD accompanies more predictable execution on the CPU and system, while likewise offering burden adjusting and auto-scaling though BASIC does not offer these components. A virtual machine format is a library resource that involves a hardware profile, a virtual hard plate, and an optional guest working structure profile. Formats give a regulated assembling of hardware and programming settings that you can use to make different new virtual machines organized with those settings. The essential contrasts are STANDARD accompanies more predictable execution on the CPU and system, while additionally offering burden adjusting and auto-scaling though BASIC does not offer these elements. Explain in detail some enhancements of the VMware tools device drivers? The VMware Tools establishment contains numerous gadget drivers which help to improve execution. It relies on upon the Operation System which ones get introduced, yet this is a rundown of what can be enhanced as * SVGA Driver – Enables 32-bit shows, high show determination and speedier design execution. On windows based frameworks who are vista or later the VMware SVGA 3D (WDDM) driver is introduced to bolster Aero. * SCSI Driver – If you determine to utilize a Bus Logic Adapter, the visitor OS utilizes this driver. Some late visitor OSes will contain LSI Logic Parallel or......

Words: 396 - Pages: 2

Cis512 Week 9 Assignment 4 the Virtual Memory Manager (Vmm) Cis 512 Week 9 Assignment 4 the Virtual Memory Manager (Vmm)

...mistakes because of precision errors. When using floating point numbers, one must make sure that the correct number of digits is used in a calculation because rounding errors can produce values that lead to errors. Consider the floating point format, exponential format, and binary coded decimal (BCD). Write a four to five (4-5) page paper in which you: 1. Analyze the floating point format in order to: a. Determine how floating point numbers are stored in memory. b. Discuss the ease or difficulty of manipulating and using floating point numbers in arithmetic calculations. 1. Determine whether or not you believe that the floating point format is memory efficient. Provide a rationale to support your answer. 2. Analyze the format used to store numbers using the binary coded decimal format. Determine whether the BCD format is more or less memory efficient than the floating point format. 3. Compare and contrast the BCD format to the floating point format in terms of: a. precision b. performance in calculations c. memory usage 1. Select the format (floating point format, binary coded decimal (BCD), or exponential format) that you would recommend for processing efficiency and explain why. 2. Floating point numbers can introduce rounding errors in the banking industry, which may lead to financial benefit for the bank but not for the customer. Analyze the ethics of knowingly benefitting from rounding errors. Propose a plan on how the rounding error should be handled. ......

Words: 2720 - Pages: 11

Virtual Memory and Paging

... (a) Virtual memory can be based on Paging only, Segmentation only or a combination of the two. (i) With the help of a diagram, show how a virtual address is translated into a physical address in a paging-based memory management scheme OR in a segmentation-based memory management scheme. The mechanism used for reading a word from memory involves the translation of a virtual address consisting of page number and offset into a physical address, consisting of frame number and offset and this translation is done using a page table. Figure 1 shows the structure of paging mechanism. When a particular process is running, a register holds the starting address of the page table for that process. The page number of a virtual address is used to index that table and look up the corresponding frame number. This is combined with the offset portion of the virtual address to produce the desired physical address. Figure 1: Adress Translation in a paging-based memory management (ii) What is the memory management technique used in Linux? Demand paged virtual memory is used as memory management technique in Linux. It is a dynamic memory allocation technique that consists of deferring page frame allocation until the last possible moment which can be the moment when a process attempts to access a page that is not present in RAM. The basic unit of memory allocation for this technique is page and the page size is 212 (4096 bytes or 4KB). (iii) Every virtual memory......

Words: 621 - Pages: 3

Cis 512 Wk 9 Assignment 4 the Virtual Memory Manager

...512 WK 9 ASSIGNMENT 4 THE VIRTUAL MEMORY MANAGER To purchase this visit here: Contact us at: SUPPORT@ACTIVITYMODE.COM CIS 512 WK 9 ASSIGNMENT 4 THE VIRTUAL MEMORY MANAGER CIS 512 WK 9 Assignment 4 - The Virtual Memory Manager Most operating systems use a virtual memory manager (VMM) whose responsibility is to manage the relationship between the virtual organization of memory as seen by an application with the physical organization of memory from the operating system’s point of view. Virtual memory addresses must be mapped to physical address and vice versa. Write a four to five (4-5) page paper in which you: 1. Differentiate between virtual memory and physical memory. 2. Evaluate the benefits gained by running applications when the operating system uses a virtual memory manager. 3. Analyze how virtual memory addresses get translated into physical addresses. Analyze how a modern operating system translates 32-bit and 64-bit virtual addresses to physical addresses on the same machine. More Details hidden... Activity mode aims to provide quality study notes and tutorials to the students of CIS 512 WK 9 Assignment 4 The Virtual Memory Manager in order to ace their studies. CIS 512 WK 9 ASSIGNMENT 4 THE VIRTUAL MEMORY MANAGER To purchase this visit here: Contact us......

Words: 631 - Pages: 3