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How
can we improve memory utilization and system
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performance
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Processes
have parts
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Code
program and maybe shared libraries
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Data
pre-allocated and heap
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Stack
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Solution
slightly more Memory Management hardware
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Multiple
sets of base and limit registers
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Divide
process into logical pieces called segments
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Segmentation
advantages
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Code
segments dont need to be swapped out and may be shared
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Stack
and heap can be grown may require segment swap
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With
separate I and D spaces can have larger virtual address spaces
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I
= Instruction (i.e., code, always read-only)
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D =
Data (may be read-write)
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