• Introduction to Memory Management
• Comparison of Windows NT & Linux:
• Conclusion
Diarmuid Ryan (11363776)
• Windows Memory Management System
Songjun Lin (12251990)
• Linux Memory Management System
Contents:
Introduction (Maria)
Windows Version (Diarmuid)
History
Paging
Virtual Memory/Address Space
Page Swap
File Mapping
Linux Version (Songjun Lin)
History
Structure of Memory Management
Virtual Memory/Address Space Paging
Page Swap
BitMap/Table
Comparison (Maria)
Conclusion (Maria)
Bibliography (Maria)
Introduction to Memory Management in Linux & Windows:
Memory management is important in all operating systems, the speed at which the processes can be run is affected by their location, whether it is currently stored in memory or on disk, the location in turn affects the speed, as processes which are located in memory do not require additional time to be loaded in from disk. Memory Management is also important for efficient use of the memory, to have as little fragmentation or unusable space as possible. The location of data and how it is stored and retrieved are all part if memory management. The methods by which memory is managed is not standard across operating systems. To investigate the differences between memory management in different systems these key areas must be looked at.
Paging is when the memory is partitioned into relatively small pieces of a fixed size and processes are broken up into chunks the same size as these partitions, they are known as pages. Page frames are sections of memory to which pages can be assigned.
Page Tables allow pages to be stored non-contiguously in memory, each page has an associated page table with a logical ...
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...writes to it’s own new version.
Conclusion:
There are many small differences between the two operating systems and on the surface of it is impossible to tell which system is better it appears to be more a preference. This seems it will always be the case while the optimal solutions are still theoretical or impossible to implement. This is also because there are many small other factors which contribute to how efficient either of these can be and they are completely unpredictable. The methods used by the two system try to ensure efficient memory management for these unknown variables,however with these unknow things like optimum page size can not be determined and systems can only try to predict what process page is least likely to be needed in the future there is no absolute way to gain this information as over time the requirements are constantly changing.
This memory is assists in allowing the computer to simultaneously read and write data at the same time. Simply put, RAM is the most common form of memory that is utilized by computers as well as other devices. There are specific types of RAM that include dynamic random access memory and static random access memory, or DRAM and SRAM respectively. These two RAM are very different in terms of how they allow data to be read and written. Dynamic random access memory is often considered the most frequent type found in computers. Static random access memory is also found in computer, and is usually referred to as the faster of the two types due to the fact that refreshing of this form of memory is not needed whereas with dynamic random access memory it is. The term RAM is often used to describe what the computer uses to function. It is the main memory or primary memory whereby all processes and software run. Since it is random access memory, it is only available at the time a certain process is needed and is not stored anywhere on the computer specifically (2007). This is what makes random access memory often confusing to understand particular since computers also have what is known as read only
“Ubuntu is probably the most well-known Linux distribution. Ubuntu is based on Debian, but it has its own software repositories. Much of the software in these repositories is synced from Debian’s repositories. The Ubuntu project has a focus on providing a solid desktop (and server) experience, and it isn’t afraid to build its own custom technology to do it. Ubuntu used to use the GNOME 2 desktop environment, but it now uses its own Unity desktop environment. Ubuntu is even building its own Mir graphical server while other distributions are working on the Wayland. Ubuntu is modern without being too bleeding edge. It offers releases every six months, with a more stable LTS (long term support) release every two years. Ubuntu is currently working on expanding the Ubuntu distribution to run on smartphones and tablets (hottogeek).” Ubuntu has a reputation for ease of use, which is why it’s popular on many desktops and servers. Ubuntu also helps users keep up with the latest software versions by releasing updates on a regular schedule. The drawback of frequent updates is that it's harder to keep bugs from slipping into the mix. To this end Ubuntu releases an LTS version periodically, which stands for "Long-Term Support". The LTS version uses package versions that are considered more stable than cutting-edge, making it more suitable for use on a production server than the interim Ubuntu releases. If you're completely lost as to which distribution to run Ubuntu LTS is a safe place to start. Its widespread adoption means there are several forums and sites on the Internet that provide help resources for Ubuntu
Have you ever wondered what allows us to be aware of the present? It is actually the past! Without knowledge of past information, we would be constantly confused during the present and incapable of almost everything. Hockenbury & Hockenbury (2012) describes memory to be, “…the mental processes that enable us to acquire, retain, and retrieve information”. Without the presence of either of these three processes, the other two would be obsolete. Many experiments have been conducted to better understand these processes and break them down into their basic components.
of as an inner ear. It is now thought to be made up of two components
In this experiment we replicated a study done by Bransford and Johnson (1972). They conducted research on memory using schemas. All human beings possess categorical rules or scripts that they use to interpret the world. New information is processed according to how it fits into these rules, called schemas. Bransford and Johnson did research on memory for text passages that had been well comprehended or poorly comprehended. Their major finding was that memory was superior for passages that were made easy to comprehend. For our experiment we used two different groups of students. We gave them different titles and read them a passage with the intentions of finding out how many ideas they were able to recall. Since our first experiment found no significant difference, we conducted a second experiment except this time we gave the title either before or after the passage was read. We found no significant difference between the title types, but we did find a significant difference between before and after. We also found a significant title type x presentation interaction. We then performed a third experiment involving showing objects before and after the passage was read. There we did encountersome significant findings. The importance and lack of findings is discussed and we also discuss suggestions for future studies, and how to improve our results.
As the internet is becoming faster and faster, an operating system (OS) is needed to manage the data in computers. An Operating system can be considered to be a set of programed codes that are created to control hardware such as computers. In 1985 Windows was established as an operating system and a year earlier Mac OS was established, and they have dominated the market of the computer programs since that time. Although, many companies have provided other operating systems, most users still prefer Mac as the most secured system and windows as it provides more multiple functions. This essay will demonstrate the differences between windows
Windows hardware’s has played a vital role in current technology of computer era. Computer application has significantly changed the workloads and manual records and information keeping has been significantly managed easily. This has been tremendously associated with the respective improvements with the software and hardware application development and Windows Xp and windows 7 have been most powerful operating system used by many computer applicants and users.
Virtualization technologies provide isolation of operating systems from hardware. This separation enables hardware resource sharing. With virtualization, a system pretends to be two or more of the same system [23]. Most modern operating systems contain a simplified system of virtualization. Each running process is able to act as if it is the only thing running. The CPUs and memory are virtualized. If a process tries to consume all of the CPU, a modern operating system will pre-empt it and allow others their fair share. Similarly, a running process typically has its own virtual address space that the operating system maps to physical memory to give the process the illusion that it is the only user of RAM.
[7] Elmasri & Navathe. Fundamentals of database systems, 4th edition. Addison-Wesley, Redwood City, CA. 2004.
The Linux file system does things a lot more differently than the Windows file system. For starters, there is only a single hierarchal directory structure.
Paging is one of the memory-management schemes by which a computer can store and retrieve data from secondary storage for use in main memory. Paging is used for faster access to data. The paging memory-management scheme works by having the operating system retrieve data from the secondary storage in same-size blocks called pages. Paging writes data to secondary storage from main memory and also reads data from secondary storage to bring into main memory. The main advantage of paging over memory segmentation is that is allows the physical address space of a process to be noncontiguous. Before paging was implemented, systems had to fit whole programs into storage, contiguously, which would cause various storage problems and fragmentation inside the operating system (Belzer, Holzman, & Kent, 1981). Paging is a very important part of virtual memory impl...
Both operating systems however diverge from each other in various ways, their question isn’t necessary which one is better but rather what makes them so different. When comparing two operating systems a user should take the following categories in for consideration, cost, user, user interface, usage, file system support, and security. The cost of a Linux operating is completely free versus a windows operating system which can range from prices such as $50.00 to $450.00. Even though Linux operating system is free however according to diffren.com their customer support is available for a
Computers are very complex and have many different uses. This makes for a very complex system of parts that work together to do what the user wants from the computer. The purpose of this paper is to explain a few main components of the computer. The components covered are going to be system units, Motherboards, Central Processing Units, and Memory. Many people are not familiar with these terms and their meaning. These components are commonly mistaken for one and other.
There are four types of memory. These are the RAM, ROM, EEPROM and the Bootstrap loader. The RAM, also known as Random Access Memory, is the temporary space where the processor places the data while it is being used. This allows the computer to find the information that is being requested quickly without having to search the hard drive space. Once the information has been processed, and stored onto a permanent storage device, it is cleared out of the RAM. The RAM also houses the operating system while in
It can be identified as the quantity of data transferring between nodes toward the end of execution stage as this is the data that will be processed further in the execution stage. In the DSM system the quantity of data sharing between nodes is normally based on different physical page-size. The system utilizing paging, in spite of the measure of data sharing, the measure of data transferring between nodes is normally based on different physical page size of the fundamental architecture. Issue emerges when system that comprises very small data granularity are running on system that backing very large physical pages. On the off chance that the shared data is saved in adjacent memory area then most data can be saved in couple of physical pages. Subsequently lower the efficiency of system as the common physical page hits between multiple processors. To resolve this issue the DSM system subdivided the shared data structure on to disjoint physical