FoundationNumeric answer
Walking a matrix through the cache · Part 1 of 3
A 1,024 × 1,024 matrix of float64 is stored row-major (C order), starting on a cache-line boundary. A cache line is 64 bytes, and at the start none of the matrix is cached. The cache holds 512 lines, far fewer than the matrix needs, and evicts the least recently used line.
You sum the matrix row by row. How many cache lines are loaded from memory?
Answer with a number. Fractions, powers and expressions like 23/6 or C(52,5) are read correctly in practice.
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