Essay on Linex VS Mac VS Windows 02 16 2014

Submitted By entenduam2
Words: 2553
Pages: 11

The operating systems Linux®, Macintosh® (Mac) and Microsoft® Windows® are the main software to every computer system to run properly along with other hardware. These operating systems (OS's) are very different in several ways, but they also have some similarities too. Linux, Mac and Windows use memory management, process management, file management and security management to operate the computer systems correctly. The first management to compare and contrast between the three OS is memory management. Memory management is a process of handling computer memory to different programs to operate a system effectively. This type of management in computers involves storing physical data using RAM, chips, memory caches and virtual memory. The largest similarity between the three is they help manage the memory to optimize performance in a system. The difference between the three is the dissimilar ways they handle the memory. For example, one OS may use virtual memory only, or another OS may use physical and virtual memory together.
Linux memory management has a 32 and 64 bit addresses to store memory. Linux uses paging to manage their memory. The 32 bit uses 4 GB data, and the 64 bit uses 2 petabytes of data. The way the paging works for Linux is it has three levels of types of pages called page global directory, page middle directory and page tables. Two of the pages are the main ones used, but the page middle directory has one entry. The Linux
OS splits the 4 GB address space into the 3 GB where it finishes or processes the data.
Windows uses very different memory management than Linux. It uses a virtual memory manager, lazy allocation, prefetching and page file. The virtual memory manager is responsible for organizing the memory. The lazy allocation is to avoid

allocating memory that is not needed. Prefetching moves pages from disk to memory.
Pagefile stores the pages are too big to fit in the main memory. Windows also uses 32 bit, and 64 bit virtual address space like Linux. The 64 bit is the space, which Linux had the 2 petabytes. Windows memory goes from page directory register to page directory table. Then it goes into page table where it is then saved in page frames to a physical address. Linux goes through one extra table before it is sent into the page frame with a physical address.
Mac OS does things a little differently than Linux and Windows. Mac has over 4
GB of space, which uses 32 bit of addressable space per process. It also provides 18 exabytes in a 64 bit addressable space. The Mac OS barely uses RAM memory to move memory around to complete tasks. It uses a hard disk for all the memory that is not being used which this gives the processes the entire address space to complete processes. Mac uses paging to complete processes as well. Each page has 4 kilobyte.
Wired Memory is also something Mac uses that contains about 17 megabytes to a 128 megabyte system. Typically, Mac has more memory in their OS to move memory around. Process Management
Process management in Linux, Windows, and Mac are similar in that you need to understand each process, what it is, and who or what is using the process before you make any attempt to stop the process. Each system has a different way to interact with running processes. For example, if you were to look at the running processes in Linux you could issue the top command or the ps command, from the command line. In

Windows you could use the Task Manager or Windows Process Explorer to view the running processes. On a Mac, you could use ps from a terminal window or use the GUI task manager. Unlike Mac and Linux, the Windows task manager does not show the process ID (PID) by default, you need to enable the option manually, to view the PID. Linux Process Management
Linux is a multi­user operating system, which means multiple users can use the
OS at the time without any issues. However, each user does not have to be logged into