On Wed, 7 Oct 2009, Andi Kleen wrote: > > It won't double it, because there are many more cache lines from > all kinds of other things in these paths. Not all that many. The big part of the D$ is the hash table lookup in this path. > The point was just to hide the latency of fetching two at different > times. The actual cache foot print is not that important, as long as > it's not excessive You're full of sh*t. Every extra line you fetch pushes out another line. No amount of prefetching will hide that. So stop spreading idiotic fairytales. The best optimization is to not do the work at all. It really is that simple. Prefetching as an optimization technique absolutely sucks. Linus -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
