Page 72 - slides.dvi
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•
                                         •
                 •
                             –
                        –
   Operating

                                                     When
            virtual
                                                various
   Systems
                 Contrast
                                    collection
                        Logical
   —
                                    of
                             Segments
                                                sizes,
                                         Segmentation
                 with
            address
                                                                                                               Segmentation
                             have
                                                with
   Segmentation
                             a
                        addresses
                                                     programming,
                 paging
                                                no
            space,
                                    (typically
                                                     a
                                         supports
                                                                                   main()
            all
                                                                           2
                                                                                              procedure
                                                                                           0
                             name
                                                     user
                                         this
                        specify
                 where
                             (or
                                                                    sys library 3
                                    disjoint)
                                                                                          stack
                             a
                                                particular
                                                                              symbols
                 user
                                                                                         1
                                                                            4
            managed
                                                     prefers
                 is
                        segment
                                         user-view
                                                     to
                                                                                                     Space
                                         of
                                                ordering
                             number)
                                                                                                           Logical
                        and
                                                                                                        Address
                                    segments.
                                                                                    2
                                                                                       1
                                                                                          0
                                                     view
                                                                              4
                                                                                 3
                 unaware
                             and
                 of
                                                                                       200
                                                                              300
                                                                                 200
                                                                                    5000
                                                                                           1000
                                                                                             Limit
                             a
                        offset.
            transparently
                                         memory
                                                                  Table
                                                                     Segment
            by
                                                                                    200
                                                                              5300
                                                                                           5900
                                                                                       0
                                                                                 5700
                                                     memory
                                                                                             Base
                                         —
                                                     as
                             length.
                 memory
                                                     a
            OS).
                                                                                                    0
                                                                                                 200
                                                                                    5200
                                                                           5600
                                                                         5700
                                                                    5900
                                                             6900
                                                                                5300
                                         logical
                                                     set
                                                     of
                                                                                                  stack
                                                                                              main()
                                                                             symbols
                                                                 procedure
                                                                       sys library
                                                                                                       Memory
                                                                                                          Physical
                 structure
                                         address
                 (one
                                                     “objects”
                                         space
                 big
                                                     of
                                         is
                                         a
                 linear
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