Page information in memory is also called as Page Table. The essential contents in each entry of a page table is/are.

The essential content in each entry of a page table is the page frame number.

Explanation:

In paging, physical memory is divided into fixed-size blocks called page frames and logical memory is divided into fixed-size blocks called pages which are of the same size as that of frames. When a process is to be executed, its pages can be loaded into any unallocated frames from the disk.

In paging, mapping of logical addresses to physical addresses is performed at the page level.

• When CPU generates a logical address, it is divided into two parts: page number and offset
• Page size is always in the power of 2.
• Address translation is performed using the page table (mapping table).
• It stores the frame number allocated to each page and the page number is used as an index to the page table.

When the CPU generates a logical address, that address is sent to the MMU (memory management unit). MMU uses the page number to find the corresponding page frame number in the page table. Page frame number if attached to high order end of page offset to form physical address that is sent to the memory.

The mechanism is shown here: