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Procedure

We start by fixing the size of the Linear space (L) since that will determine the max amount of physical memory allowed in the system.

Then we fix the size of the page frames (F). Here is a trade-off situation: The smaller is F, the bigger becomes the Matrix; but making F too big will degrade memory management efficiency. We can start with a reasonable value (say, 4KB).

With these two variable fixed, we can start doing the math


#Linear Address fields:

d = log2 (F)   ; Number of bits in the OFF_SET field
P = L - d      ; Number of bits in the PAGE field

#Matrix entry:

A = P          ; Number of bits in the FRAME_ADDRESS field.

The Matrix entry also has control bits (about 4) and can also contain reserved bits. What we do is to add them all, then we round to a multiple of 4 (for practical reasons). Extra bits resulting of rounding will be considered "reserved".

#Trans Table size:

Trans Table is the chunk of Matrix dedicated to one process. The number of entries is:

N = 2^P

So far we have a Matrix that is N rows by A bits... per process.

#Matrix size:

The Matrix has as many trans tables as simultaneous processes are allowed (S). This is another trade-off situation. In this step we fix S seeking a comfortable value with acceptable cost in Matrix RAM.

M = N * S

The final size of the Matrix is M rows by A bits.