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Unformatted text preview: ect-mapped caches, sets and lines are indeed equivalent. However, in associative caches, sets and lines are very different things and the terms cannot be used interchangeably. Since a line always stores a single block, the terms “line” and “block” are often used interchangeably. For example, systems professionals usually refer to the “line size” of a cache, when what they really mean is the block size. This usage is very common, and shouldn’t cause any confusion, so long as you understand the distinction between blocks and lines. End Aside. 6.5 Writing Cache-friendly Code
In Section 6.2 we introduced the idea of locality and talked in general terms about what constitutes good locality. But now that we understand how cache memories work, we can be more precise. Programs with better locality will tend to have lower miss rates, and programs with lower miss rates will tend to run faster than programs with higher miss rates. Thus, good programmers should always try to write code that is cache-friendly, in the sense that it has good locality. Here is the basic approach we use to try to ensure that our code is cache-friendly. 1. Make the common case go fast. Programs often spend most of their time in a few core fun...
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