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Batch Processing Operating System

Batch processing system · Batch processing is one of the oldest method of running the programs · The computer in the past were very large in size and their I/O devices were very different from those that are used today. The job processing was not interactive as it is today. · The user did not interact directly with computer system. · The process scheduling , memory management, file management and I/Omanagement functions are quite simple in batch processing system 1. Process scheduling (i.e. allocation strategy for a processor is typically in order of their arrival i.e. first come first served(FCFS)basis. 2. Memory management is done by divi...

Multi processing system

Multi processing system · Multi processesor system is the sytem that contain two or more processors or CPUS and has ability to simultaneously execute several programs. Hence the name multi-processor In such a system, multiple processor share the clock, bus, memory and peripheral devices. · A multi processor system is also known as parallel system · Multi processor system are categorized into two different types: single user operating system 2. Multi user operating system 3. Batch processing operating system 4. Multi programming operating system 5. Multi tasking operating sy...

Virtual Machine Architecture

Virtual Machine Architecture A virtual machine can exist as a standalone machine or it can exist within a vApp. A virtual machine is a software computer that, like a physical computer, runs an operating system and applications. The virtual machine consists of a set of specification and configuration files and is backed by the physical resources of a host. Every virtual machine has virtual devices that provide the same functionality as physical hardware are more portable, more secure, and easier to manage. Virtual machines can be standalone, or they can exist within a vApp. A vApp is compound object composed of one or more virtual machines as well as one or more networks. 1. Monolithic architecture 2. Layerd archtecture . 3. Virtual machine architecture 4. Exokernel architecture 5. Client server architecture 6. Micro kernel architecture The following figure ...

Multilevel Feedback queue scheduling (MFQ)

Multilevel Feedback queue scheduling (MFQ) · Multilevel feedback queue scheduling is an enhancement of multi-levelqueue scheduling. In this scheme, processes can move between the different queue · The various processes are separates in different queue on the basis of their CPU Burst Char characteristics · If a process consumes a lot of CPU time , it is placed into a lower priority queue. Thus I/O bound and interactive process are placed in the higher priority queue and CPU bound pricesses are in lower priority · If a processes waits too long in a lower priority queue it is moved higher priority queue. Such an aging prevents starvation. · The top priority queue is given smallest CPU time Quantum · ...

Multi threading operating system

Multi threading operating system · Multi threading is a technique in which a process, executing an application is divided into threads that can run concurrently · A thread is a dispatch able unit of work. It includes a processor context and its own data area for sack . · A thread execute sequentially and is interruptible so that the processor can turn to another thread. · Thus, a thread represents a light weight process and is the smallest unit of CPU utilization it is like a mini process. · A process, on other hand is a collection of one or more threads and associated system resources · A thread is not a process by itself. Cannot run on...

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