CST 334 Week 3

    This week introduced the concept of memory virtualization, where the operating system maps virtual addresses to physical memory, creating a separate virtual address space for each process. The primary goals of memory virtualization are transparency, efficiency, and protection:

  • Transparency ensures that the virtualization is invisible to the program.
  • Efficiency improves the utilization of physical memory, enabling better memory management.
  • Protection isolates the memory spaces of different processes to prevent interference.

    To implement memory virtualization, the OS uses address translation, where virtual addresses are mapped to physical addresses in RAM. This process is managed by the Memory Management Unit, which ensures both efficiency and protection of memory.

    A key technique in memory virtualization is segmentation, where a program's virtual address space is divided into logical segments. Each segment can vary in size, providing more flexibility in memory usage. The OS tracks the locations of these segments using segment tables, allowing it to manage the virtual address space effectively.

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