We present a study of implementations of DGEMM using both the cache-oblivious and cache-conscious programming styles. The cache-oblivious programs use recursion and automatically block DGEMM operands A,B,C for the memory hierarchy. The cache-conscious programs use iteration and explicitly block A,B,C for register files, all caches and memory. Our study shows that the cache-oblivious programs machieve substantially less performance than the cache-conscious programs. We discuss why this is so and suggest approaches for improving the performance of cache-oblivious programs.
By: J. Gunnels; F. Gustavson; K. Pingali; K. Yotov
Published in: RC24172 in 2006
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