On 11/01/2013 04:17 PM, Davidlohr Bueso wrote: > While caching the last used vma already does a nice job avoiding > having to iterate the rbtree in find_vma, we can improve. After > studying the hit rate on a load of workloads and environments, > it was seen that it was around 45-50% - constant for a standard > desktop system (gnome3 + evolution + firefox + a few xterms), > and multiple java related workloads (including Hadoop/terasort), > and aim7, which indicates it's better than the 35% value documented > in the code. > > By also caching the largest vma, that is, the one that contains > most addresses, there is a steady 10-15% hit rate gain, putting > it above the 60% region. This improvement comes at a very low
I suspect this will especially help when also using automatic numa balancing, which causes periodic page faults. Acked-by: Rik van Riel <r...@redhat.com> -- All rights reversed -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
