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Operating System: Case Study 6

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Diagram 1.1: The Process State In the Process State diagram, jobs move through the system. There are five stages Hold, Ready, Waiting, Running, and Finished. When a process is first created, it occupies the hold state. In this state, the process awaits admission to the "ready" state. This admission will be approved or delayed by process scheduler. Typically in most desktop computer system, this admission will be approved automatically; however for real time operating systems this admission may be delayed. In the Reading process has been loaded into main memory and is awaiting execution on a CPU (Central Processing Unit). There may be many "ready" processes at any one point of the system execution. For example, in a one processor system, only one process can be executing at any one time, and all other "concurrently executing" process will be waiting for execution. While in the Running process is a process which is currently executing on a CPU. From thi...

Operating System: Case Study 5

There are two methods for free space allocation. First-fit memory allocation leads to fast allocation of memory space because first partition fitting the requirement. In the first loading of jobs, Job 1 which contains 100k that will search in the memory blocks to be allocated. Since Job 1 with 100k with 3 turnarounds can not be accommodate with Block 1 because of insufficient memory size. By that Job 1 will search again in the table of memory blocks. Job 1 found out that Block 2 with 200k is available for accommodation. So now, Job 1 is in Block 2. Job 2 with 10k with 1 turnaround searches for available block. Since first-fit allocation makes fitting its requirement, Job 2 will be accommodated by Block 1 with 50k. Job 3 with 3k and 2 turnaround will search in the memory blocks and found out that Block 3 with 70k is ready for accommodation. Job 4, will do the same thing, Block 4 is ready for accommodation so Job 4 is settled in Block 4. However, Job 5 is too large with 23k with 2 turna...

Operating System: Case Study 4

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Dynamic Partitions Jobs are being load to the Memory blocks. Memory size of 220k with the Operating System of 15k.   Note: Job 9 and Job 10 are not allowable to load for it is because of poor-size. Relocatable Dynamic Partitions Jobs are being load to the Memory blocks. Memory size of 220k with the Operating System of 15k.