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Figure 5.47
Sequential translation and access. |
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Figure 5.48
Parallel translation and access. |
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5.17 Overlapping the T cycle in V ® R Translation |
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There are three general approaches to avoiding the serial translation step in cache access (as shown in Figure 5.47). In order to avoid the sequential translation, the translation must be arranged so that it can be performed simultaneously with data access in the cache array (Figure 5.48). This can be done by one of three means: |
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1. Using high degrees of set associativity, so that the directory index bits are not affected by the translation. |
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2. Using a virtual cache. |
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3. Using perfectly colored pages. |
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We consider each in the following subsections. |
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