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0267-01.gif
Figure 5.2
Localities. (a) General locality. (b) Spatial locality. (c) Temporal locality.
Spatial locality: If a reference has been made to item x1, then it is likely that a reference will occur somewhere in region X1
Temporal locality: If a sequence of reference x1, x2, x3, x4 have recently been made,then it is likely that the next reference will be one of x1, x2, x3, or x4.
0267-02.gif
Spatial locality: References (shown as *) tend to cluster into distinct regions. The regions around xi and xj contain the recent references (or the working set).
0267-03.gif
Temporal locality: References tend to repeat. Memory addresses n1 and n2 tend to be repeated in a seuence of references (z indicates any other reference).

 
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