Should a 32-bit operating system operating with a segmented memory model still have a 4 GB limit ?
I read the Intel Pentium Processor Family Developer's Guide, and he claims that up to 64 TB can be mapped using a segmented memory model .
“In a segmented organization memory model, the logical address space consists of 16383 segments of up to 4 gigabytes each, or just 2 ^ 46 bytes (64 terabytes). The processor maps this 64 terabyte logical address space to the physical address space of the address translation mechanism described in Chapter 11. Application programmers can ignore the details of this mapping.The advantage of a segmented model is that the offset within each address space can be individually verified and access to each segment can be ndividualno under control.
This is not a difficult question. I just want to be sure that I understand the text correctly. If Windows or any other OS worked in a segmented model rather than a flat model, would the memory limit be 64 TB?
Update:
Intel System Documentation 3-2 3a.
http://pdos.csail.mit.edu/6.828/2005/readings/i386/c05.htm
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- http://www.jamesmolloy.co.uk/tutorial_html/4.-The%20GDT%20and%20IDT.html
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http://wiki.osdev.org/GDT_Tutorial#What_should_i_put_in_my_GDT.3F
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