Memory Management

Page Table

Most OS allocate a page table for each process. A pointer to the page table is stored in the PCB of the process. When the dispatcher start a process, it must reload the user registers and define the correct hardware page table from the stored user page-table. The hardware page table can be implemented in …

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Paging allows the physical address space of a process to be non-contiguous. It avoids the external fragmentation andthere is no need for compaction. Fragmentation problem affects the backing store (disk) of the main memory where processes are swapped in or out.The compaction is not possible due to the slow access speed of the backing store. …

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Contiguous Memory Allocation

The contiguous memory allocation uses memory partitions to allocate memory. These partitions could be fixed or variable size partitions allocated according to first fit, best fit, or wort fit method. The memory fragmentation is a common problem that affects these partition memory allocation system. Contiguous memory allocation is a method of allocating memory to OS …

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