1)multitasking: several programs running at the same time is called multitasking.2)multiuser: several users on the same machine at the same time through different terminals/from remote hosts.3)multiplatform: runs on many different CPUs, not just Intel like AMD too. 4)multiprocessor: SMP(Symetri multi processing) support is available on the Intel and SPARC platforms (with work currently in progress on other platforms), and Linux is used in several loosely-coupled MP applications. 5)multithreading: has native kernel support for multiple independent threads of control within a single process memory space. 6)runs in protected mode on the 386. ie Protected mode has a number of new features designed to enhance multitasking and system stability, such as memory protection, and hardware support for virtual memory as well as task switching It is sometimes abbreviated p-mode and also called Protected Virtual Address Mode 7)has memory protection between processes, so that one program can’t bring the whole system down. 8)demand loads executables: Linux only reads from disk those parts of a program that are actually used. 9)shared copy-on-write pages among executables. This means that multiple process can use the same memory to run in. When one tries to write to that memory, that page (4KB piece of memory) is copied somewhere else. Copy-on-write has two benefit’s: increasing speed and decreasing memory use. 10)virtual memory using paging (not swapping whole processes) to disk: to a separate partition or a file in the filesystem, or both, with the possibility of adding...Read More
Month: October 2008
The swap partition is a place where system will keep temporary files so that it can do the processing of data bit faster. Suppose your swap is getting filled and there is no raw partition left for creating swap partition on the server what we can do? At any cost your management asked you to increase the swap to improve the system performance. To come out of this situation there is one solution provided by Linux e.i we can create a swap file with in all ready existing and using partition if that partition is having sufficient free space Step 1: Switch off all the swap before any swap related work #swapoff -a Step 2: Determine what is the swap size we required(here i am taking 128 MB) and execute the following command with count equal to 131072 (because 131072 is equal to 128 M) This will create a swap file name swap file in / directory with size of 128 MB. dd if=/dev/zero of=/swapfile bs=1024 count=131072 Let me explain above command. dd is an excellent command which is used to take backups of partitions, create MBR, create empty files etc. Here dd is used to create a empty file called /swapfile by taking input file as /dev/zero with block size as 1024 byts and number of these bytes as 131072. This command will create a file with 128MB. Step 3: Now set this swap file in order...Read More
Before doing any thing about swap we should know what is swap, for what purpose the swap is useful and other stuff related to swap management. What is a swap in Linux? When we are running applications in Linux their frequently used data is stored in RAM for frequent access. If the applications uses the full RAM there is a possibility of system slowness. The left solution is to increase RAM size so that we can run those applications without any issue. As RAM is bit costly, buying it is not preferred plan A option. So people come with a...Read More
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My name is Surendra Kumar Anne. I hail from Vijayawada which is cultural capital of south Indian state of Andhra Pradesh. I am a Linux evangelist who believes in Hard work, A down to earth person, Likes to share knowledge with others, Loves dogs, Likes photography. At present I work at Bank of America as Sr. Analyst Systems and Administration. You can contact me at surendra (@) linuxnix dot com.