How does a computer “know” which memory is allocated?

Question

When memory is allocated on a computer, how does it know which bytes are already occupied and cannot be overwritten?

So, if these are some bytes of memory that are not used:

[0|0|0|0]

How does a computer know if they are or not? They can be just an integer equal to zero. Or it could be an empty memory. How is this known?

Answer 1

It depends on how the distribution is done, but usually it involves manipulating the data that belongs to the allocation mechanism.

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Answer 2

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Answer 3

, , - , , . "0" , .

To tell which parts of the memory are used, you need a structure to talk about it. For example, you can split the memory into pieces and keep track of which pieces are used and which are not.

Answer 4

There are blocks of memory, they are busy or not busy. The heap has very complex data structures that organize it. But the answer to your question is too broad.