Computers as Components, 2nd Edition

5.7 Software Performance Optimization 261

Once the a[0][1] access brings that line into the cache, it remains there for the a[0][2]

and a[0][3] accesses since the b[] accesses are now on the next line. However, the scenario

repeats itself at a[1][0] and every four iterations of the cache.

One way to eliminate the cache conflicts is to move one of the arrays. We do not have to

move it far. If we move b’s start to 4100, we eliminate the cache conflicts.

However, that fix won’t work in more complex situations. Moving one array may only intro-

duce cache conflicts with another array. In such cases, we can use another technique called

padding. If we extend