Windows XP Vs Linux Ubuntu - Case Study Example

Windows XP Vs Linux Ubuntu Memory management Introduction: The invention of computer has been a most significant a milestone in the history of human race. The world witness many inventions in the field of information technology. There has been a sustained effort to improve performance of different operating systems as companies are vying to stay ahead in a competitive environment. This paper will under take the exercise of comparing the memory management of two operating systems, namely, windows XP and Ubuntu Linux. These two are very popular operating systems but uses different type of memory management techniques. What is Memory Management? Memory management is the one of the core part of the operating system. It involves the process of managing a computer memory. Its basic function is to manage the hierarchy of Random Access Memory and hard disks available on a machine. Its important tasks include allocation and de-allocation of memory. The memory system should be optimized to increase overall performance and speed of the system. The task of managing memory comprises providing appropriate ways to allocate portions of memory to different programs as they require it, and freeing (or de allocating) it for reuse when no longer needed.Memory managing also takes care of logistics, and implementation of Virtual Memory by utilizing hard disk as extra RAM. Virtual memory: Virtual memory is an important concept in the context of Memory Management system. The growing memory requirements of application programs triggered the idea of Virtual Memory. Operating System will provide this facility by making use of secondary storage - the hard disk - to fulfill the extra memory requirement. The allocation and de-allocation of the data to the Virtual Memory is called Swapping. The process of saving inactive virtual memory pages to secondary storage -hard disk- and restoring them to real memory when required is called Paging. In Paging, both virtual and real address space is divided into fixed-sized (though they can be multiple sized) pages. The pages can be individually manipulated and located at different places in the physical memory and the hard disk. The address translation is actually done by the Memory Management Unit (MMU) of the processor by the use of a Page. (Khetan 2002). Comparison of Memory management in Windows XP and Linux Ubuntu: Windows is a closed source desktop operating system, while Linux is an open source version of UNIX file system and is used as a powerful, low-cost operating system for running servers. Ubuntu is a computer operating system based on Linux. Windows XP and Linux have modern MM systems, and surprisingly both has a lot in common. The data structures are quite similar, and may of the features are also comparable. Some of the similarities of these systems are enumerated below – Hardware Abstraction Layer: These two have a layer called the hardware abstraction layer (HAL) which does the system-dependent work, and thus enables the rest of the kernel to be coded in platform independent fashion. This eases the need for porting it to other platforms. Copy-on-write: When a page is to be shared, the system uses only one page with both processes sharing that same copy of the page. However, when one of the processes does a write onto the page, a private copy is made for that process, which it can then manipulate individually. This enhances the efficiency of the operating system. Shadow paging: A shadow object is created for an original object in such a manner that the shadow object has some of its pages modified from the original object, but shares the rest of the pages with the original object. These are formed as a result of Copy-On-Write action. A Background daemon: There exists a background daemon which is invoked periodically and performs tasks like page flushing, freeing unused memory, etc. Memory mapped Files: A file can be mapped onto memory, which then can be used with simple memory read/write instructions. Inter-Process Communication: The memory mapped files are allowed to be then shared between processes forming a method for inter process communication. (Khetan 2002). Linux and Windows RAM & virtual memory management techniques remain fundamentally different. One could describe the Windows model as the one that frequently sacrifices stability to achieve efficiencies that wind up putting your entire systems usability at the mercy of the programmers of the individual apps you are running, where as the Linux kernel seems to accept the fact that certain kinds of allocation techniques are fundamentally unwise, thereby dragging itself to a certain degree of inefficiency right from the start. XP employs a dynamically allocated page-file for its memory management. For less frequently accessed files, a page-file is allocated on disk leaving more RAM for frequently accessed or active files. In this case disk fragmentation causes slow down, which reduces the speed at which the objects or files can be brought back into the memory as and when needed. However windows XP can be configured to place the page-file on separate partition. By doing this the fragmentation issues can be reduced, but it introduces an I/O slowdown. Since the page-file is on separate partition, Windows cannot create a memory dump in the event of a stop-error. So a solution is to have a page-file on a separate hard drive to the primary one. This eliminates both I/O problem and fragmentation. Linux utilize an area called Swap Partition. Here the disk space allocated for paging is separate from general data and is used strictly for paging operations. Therefore slowdown due to disk fragmentation from general use is reduced. To optimize the performance the swap partition should be placed on a hard drive separate from the primary partition. RAM Performance Tests: Purpose: The purposes of the tests are for finding the performance of the RAM by comparing the speed under the operating systems Windows XP and Ubuntu Linux. Test System Configuration: Hardware Configuration: Processor : AMD Athlon 64 bit (3200+) 1.99GHz RAM : 512MB, DDR1 HDD : 40GB SATA Software Configuration: OS : Windows XP SP2 , Ubuntu 6.06System Setup The 40GB hard disk is divided into two equally partitions. First partition is formatted as NTFS partition and Windows XP is installed on it. The second partition is used to install Ubuntu Linux with the EXT3 filesystem. No software are installed other than the device drivers. Test 1: Compare the memory usage of Mozilla Firefox under Windows XP and Ubuntu Linux: Procedure: After the start up of the system in Linux, install Firefox version 3 in it. After the installation, run Firefox. Measure the memory level at each second from 0th second to 10th second. Install the same version of Firefox in Windows. Run Firefox. Measure the memory level at each second from 0th second to 10th second. Compare the results. Result Data: The result data is shown below as a graph. The maximum extra memory utilization to load Firefox are 10.1MB (for Linux) and 44MB (for Windows XP). This shows that Windows need higher memory to load Firefox. Test 2: Compare the memory usage of GIMP Image Editor under Windows XP and Ubuntu Linux: Procedure: After the start up of the system in Linux, install GIMP Image in it. After the installation, run GIMP Image Editor. Measure the memory level at each second from 0th second to 10th second. Install the same version of GIMP Image Editor in Windows. Run GIMP Image Editor. Measure the memory level at each second from 0th second to 10th second. Compare the results. Result Data: The result data is shown below as a graph. The maximum extra memory utilization to load GIMP Image Editor are 15.2MB (for Linux) and 22MB (for Windows XP). This shows that Windows need higher memory to load GIMP Image Editor. Test 3: Compare the memory usage of Tux Paint under Windows XP and Ubuntu Linux. Procedure: After the start up of the system in Linux, install Tux Paint in it. After the installation, run Tux Paint. Measure the memory level at each second from 0th second to 10th second. Install the same version of Tux Paint in Windows. Run Tux Paint. Measure the memory level at each second from 0th second to 10th second. Compare the results. Result Data: The result data is shown below as a graph. The maximum extra memory utilization to load Tux Paint is 29.2MB (for Linux) and 40MB (for Windows XP). This shows that Windows need higher memory to load Tux Paint. Conclusion: The experiments show that Windows use more memory to load softwares. File Systems: The various types of Windows file systems are FAT12, FAT16, FAT32, ISO 9660, UDF and NTFS with NTFS best choice. Third party drivers are available for ext2, ext3, HFS etc. The FATx file systems are older and have limitations on file and partition size that make them error prone in the current environment. Linux also has its own native file systems like EXT3, EXT 4, ReiserFS, NFS, ISO 9660, UDF etc. Earlier the default file system for Linux used to be EXT 2, now it is replaced by EXT 3. The EXT 3 file system is being replaced by EXT 4. The improvements in EXT 4 are, increase in the maximum file system size from 16 terabytes in EXT 3 to one Exabyte. The largest file in EXT 3 is 2 terabytes, in EXT 4 it is 16 terabytes. Open Solaris includes ZFS which seems like a drastic change in file system design. Every File System uses directories and subdirectories. Windows separates directories with a back slash whereas Linux uses a normal forward slash. Windows file names are not case sensitive whereas Linux’s is. File Hierarchy structure: Ubuntu (Linux) and WindowsXP use different file hierarchy structure. Windows uses a volume based file structure. Linux uses a unified scheme. Windows uses letters of alphabet to represent different devices and different partitions. With Windows, you need to know what volume (C:, D:, ….) a file resides on to select it, the file’s physical location is part of its name. In Linux all directories are attached to the root directory, which is identified by a forward slash "/". For example, below are some second-level directories:  /bin/ ---- system binaries, user programs with normal user permissions /data/ --- a user defined directory Every device and hard disc partition is represented in Linux File System as a subdirectory of the lone root directory. There are no standards in Linux for which subdirectories are used for which devices. This contrasts with Windows where the A disk is always the floppy drive and the C disk is almost always the boot partition. Comparison of Linux and Windows Filesystems: Comparing with EXT3, NTFS filesystem has weak work permissions and ownership options. In case of heavy data transfer, for EXT3 partitions there is a little or no increase in CPU load. But in case of NTFS, the CPU load may vary from 9% to 45% on an average of 20%. EXT3 doesn’t fragment nearly as much as NFS and it seems more solid. Linux drivers for NTFS are probably not as fast and efficient as the Windows ones. So the NTFS filesystem is faster in Windows XP than in Ubuntu Linux. The new NTFS-3G is faster comparing the old NTFS. Filesystem Performance Tests: Purpose: The purposes of the tests are for finding the performance of the hard disk by comparing the speed under the operating systems Windows XP and Ubuntu Linux. In Windows XP, the file system is NTFS and in Ubuntu Linux, the file system is EXT3. Test System Configuration: Hardware Configuration: Processor : AMD Athlon 64 bit (3200+) 1.99GHz RAM : 512MB, DDR1 HDD : 40GB SATA Software Configuration OS : Windows XP SP2, Ubuntu 6.06 System Setup: The 40GB hard disk is divided into two equally partitions. First partition is formatted as NTFS partition and Windows XP is installed on it. The second partition is used to install Ubuntu Linux with the EXT3 filesystem. No softwares are installed other than the device drivers. Test 1: Compare the speed of the Copy process in Windows XP and Ubuntu Linux. Procedure: First create two folders /home/user1/start and /home/user1/target in Linux. Save data of size 1.5 GB into the location /home/user1/start. The total number of files in the data is 5258. Copy all the content in the /home/user1/start to the folder /home/user1/target. Measure the time needed. Delete all the content in /home/user1/target folder. Repeat this process 10 times and measure the time for each. In Windows, create folders C:\start and C:\target. Repeat the same experiment done for Linux and measure the time needed in all processes. Compare the results. Result Data: Average Copy Time – 3.22 min. for Ubuntu Linux, 4.59 min. for Windows XP. This indicate that the write time for Linux is faster than Windows. Test 2: Compare the speed of the Delete process in Windows XP and Ubuntu Linux. Procedure: In Linux, create a folder /home/user1/delete. Save data of size 1.5 GB into the location /home/user1/delete. The total number of files in the data is 5258. Delete all data in /home/user1/delete. Measure the time taken for delete. Repeat this for 10 times and measure time needed for each operation. In Windows create the folder C:\delete. Repeat the same experiment done for Linux and measure the time needed in all processes. Compare the results. Result Data: Average Delete Time – 15.43 sec. for Linux, 5.41sec for Windows. It shows that Windows is speeder in delete process. Test 3: Compare the speed of the Search process in Windows XP and Ubuntu Linux. Procedure: In Linux, create a folder /home/user1/search. Save data of size 1.5 GB into the location /home/user1/search. The total number of files in the data is 5258. Search a specific file from /home/user1/search folder using search utility. The name of the file is chosen randomly from the files in /home/user1/search folder. Measure the time taken for search process. Repeat this for 10 times and measure time needed for each operation. In Windows create the folder C:\search. Repeat the same experiment done for Linux and measure the time needed in all processes. Compare the results. Result Data: Average Search Time – 2.2 sec. for Linux, 1.28 sec. for Windows. This shows that Windows is speeder in data read operations. Conclusion: While comparing the Ubuntu Linux and Windows XP, we can see that the data read operations are faster in Windows and data write operations are faster in Linux. Conclusion: By the comparison of each test between the Windows XP and Ubuntu Linux, we cannot come to a conclusion that one is better than the other. The degree of performance of both operating systems may vary in different hardware and software configurations. It may also vary in multiprocessing environments. Both operating systems have high performance in different areas and one can choose operating system after considering his needs. Bibliography KHETAN, Gaurang. (2002). Comparison of Memory Management Systems of BSD, Windows, and Linux. [online]. Last accessed 31 January 2009 at: http://gaurang.org/academics/csci555/termpaper2.pdf Read More