On Fri, Oct 20, 2017 at 07:54:23PM +0800, Wei Wang wrote: > This patch series intends to summarize the recent contributions made by > Michael S. Tsirkin, Tetsuo Handa, Michal Hocko etc. via reporting and > discussing the related deadlock issues on the mailinglist. Please check > each patch for details. > > >From a high-level point of view, this patch series achieves: > 1) eliminate the deadlock issue fundamentally caused by the inability > to run leak_balloon and fill_balloon concurrently; We need to think about this carefully. Is it an issue that leak can now bypass fill? It seems that we can now try to leak a page before fill was seen by host, but I did not look into it deeply. I really like my patch for this better at least for current kernel. I agree we need to work more on 2+3. > 2) enable OOM to release more than 256 inflated pages; and Does just this help enough? How about my patch + 2? Tetsuo, what do you think? > 3) stop inflating when the guest is under severe memory pressure > (i.e. OOM). But when do we finally inflate? Question is how does host know it needs to resend an interrupt, and when should it do it? > Here is an example of the benefit brought by this patch series: > The guest sets virtio_balloon.oom_pages=100000. When the host requests > to inflate 7.9G of an 8G idle guest, the guest can still run normally > since OOM can guarantee at least 100000 pages (400MB) for the guest. > Without the above patches, the guest will kill all the killable > processes and fall into kernel panic finally. > > Wei Wang (3): > virtio-balloon: replace the coarse-grained balloon_lock > virtio-balloon: deflate up to oom_pages on OOM > virtio-balloon: stop inflating when OOM occurs > > drivers/virtio/virtio_balloon.c | 149 ++++++++++++++++++++++++---------------- > 1 file changed, 91 insertions(+), 58 deletions(-) > > -- > 2.7.4 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
