Operating system as resource manager: · A computer system usually has many hardware and software resources such as processor , memory, disk printer, I/O devices etc. · The task of resources management becomes essential in multi-user operating system where different user compute for the same resource. Operating system manages resources in two ways : 1. Time multiplexing : it defines the sharing of resources on the basis of fixed time slices. For example, the operating system allocate the resources, such as CPUto program A for fixed time slice. 2. Space timing: it defines the concurrent sharing of resources among different programs.for example, sharing of hard disk and main memory is space multiplexing. FUNCTION OF OPERATING SYSTEM The primar...
Suspend a process A process is an active program. It can also be said as a program that is under execution. It is more than the program code as it includes the program counter, process stack, registers, program code etc. Compared to this, the program code is only the text section. A process passes through different states as it executes. These states may be different in different operating systems. However, the common process states are explained below with the help of a diagram − New This is the state when the process has just been created. It is the initial state in the process life cycle. Ready In the ready state, the process is waiting to be assigned the processor by the short term scheduler, so it can run. This state is immediately after the new state for the process. Ready Suspended The processes in ready suspended state are in secondary memory. They were initially in the ready state in main memory but lack of memory forced them to be suspended and gets placed in the second...
Micro kernel architecture What is Kernel? A kernel is an important part of an OS that manages system resources. It also acts as a bridge between the software and hardware of the computer. It is one of the first program which is loaded on start-up after the bootloader. The Kernel is also responsible for offering secure access to the machine's hardware for various programs. It also decides when and how long a certain application uses specific hardware. What is Microkernel? Microkernel is a software or code which contains the required minimum amount of functions, data, and features to implement an operating system. It provides a minimal number of mechanisms, which is good enough to run the most basic functions of an operating system. It allows other parts of the operating system to be implemented as it does not impose a lot of policies. Microkernels and their user environments are usually implemented in the C++ or C programming languages with a little bit of assembly. Ho...
Scheduler Scheduling Objectives Here, are important objectives of Process scheduling Maximize the number of interactive users within acceptable response times. Achieve a balance between response and utilization. Avoid indefinite postponement and enforce priorities. It also should give reference to the processes holding the key resources Process Scheduling handles the selection of a process for the processor on the basis of a scheduling algorithm and also the removal of a process from the processor. It is an important part of multiprogramming in operating system. Process scheduling involves short-term scheduling, medium-term scheduling and long-term scheduling. Details about these are given as follows − Long-Term Scheduling Long-term scheduling involves selecting the processes from the storage pool in the secondary memory and loading them into the ready queue in the main memory for execution. This is handled by the long-term scheduler or job scheduler. The long-term s...
Exokernel architecture Most of us know what kernels are and how do they work to make programmers’ lives easier. But, how many of us know what exokernels are? I hope you will be able to get a brief introduction on this terminology through this blog. Let’s start with a brief introduction on kernel. What is a kernel? A kernel is the foundational layer of an operating system that functions at a basic level, communicating with hardware and managing resources, such as CPU and the memory. It works as an interface between the user application and the hardware. There are two main types of kernel 1. Micro kernel 2. Monolithic Kernel 1. Monolithic architecture 2. Layerd archtecture . 3. Virtual machine architecture 4. Exokernel architecture 5. Client server architecture 6. Micro kernel architecture Now let’s head into our main focus. What is an Exokern...
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