On Thu, Apr 23, 2009 at 09:05:35AM +0900, KAMEZAWA Hiroyuki wrote: > So, current status is. > > A. memcg should support dirty_ratio for its own memory reclaim. > in plan. > > B. another cgroup can be implemnted to support cgroup_dirty_limit(). > But relationship with "A" should be discussed. > no plan yet. > > C. I/O cgroup and bufferred I/O tracking system. > Now under patch review. > > And this I/O throttle is mainly for "C" discussion. How much testing has been done in terms of whether the I/O throttling actually works? Not just, "the kernel doesn't crash", but that where you have one process generating a large amount of I/O load, in various different ways, and whether the right things happens? If so, how has this been measured? I'm really concerned that given some of the ways that I/O will "leak" out --- the via pdflush, swap writeout, etc., that without the rest of the pieces in place, I/O throttling by itself might not prove to be very effective. Sure, if the workload is only doing direct I/O, life is pretty easy and it shouldn't be hard to throttle the cgroup. But in the case where there is bufferred I/O, without write throttling, it's hard to see how well the I/O controller will work in practice. In fact, I wouldn't be that surprised if it's possible to trigger the OOM killer....... Regards, - Ted _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/containers
