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Demand paging

Hello guys. May I ask a question?

I've been reading through the linux sources, early versions (the code is
much smaller), and I have some doubts.

Let's talk about demand paging: When a process is born (via fork, of
course), linux gives him a 64MB segment (recall I'm talking about earlier
versions). To get this, you need 16 page tables: 16*4MB = 64MB. Each page
steal 4KBytes of memory. So, you need 16 * 4KBytes = 64KBytes of 
memory space, for EACH PROCESS.

It is really this way? Think about 100 processes, they would steal 6400
KBytes, just for the page tables!!!



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