Well, it does rely on decomposing the problem to optimize cache efficiency.

I don't read Portuguese, but the tables of results seem to imply they are tuning block sizes that leverage the L3 cache. They also talk about prefetch, which tends to matter more as you are approaching a streaming pattern.

So, a single core result may not scale linearly for multicore, given that there will be some cache contention, right? It's a very different tuning problem to optimize each of N cores to use its 1/N fraction of cache while sharing the available bandwidth for cache misses.