Description: The page directory is a fundamental structure in the memory management of modern operating systems. Its main function is to store the addresses of page tables, which are used to translate virtual addresses to physical addresses in memory. This mechanism is essential for implementing virtual memory, allowing processes to use more memory than is physically available in the system. The page directory organizes information hierarchically, facilitating the search and access to the page tables corresponding to each process. Each entry in the page directory points to a specific page table, which in turn contains the translations of virtual to physical addresses. This structure not only optimizes memory usage but also enhances system security and stability by isolating address spaces of different processes. In systems with 32-bit and 64-bit architectures, the size and complexity of the page directory can vary, adapting to the needs of various operating systems and underlying hardware. In summary, the page directory is a critical component that enables efficient memory management in multitasking environments, ensuring that processes can run effectively and securely.
