* Peter Zijlstra <pet...@infradead.org> wrote: > On Sat, Sep 28, 2013 at 11:55:26AM -0700, Linus Torvalds wrote: > > So if the primary reason for this is really just that f*cking anon_vma > > lock, then I would seriously suggest: > > I would still like to see the rwsem patches merged; even if we end up > going back to a spin style anon_vma lock. > > There's been various reports in the past about how programs are > significantly faster if they wrap their mmap() calls in a pthread_mutex. > And this was purely down to the fact that rwsem writer-writer contention > blows chunks.
That's about the mm->mmap_sem rwsem, right? That impact would have to be measured carefully, and not just for workloads where we know that better contention logic helps, but other MM workloads that are hitting hard on mmap_sem. Thanks, Ingo -- 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/