On Wed, Aug 19, 2009 at 11:51:46AM +1200, Michael wrote: > Hi, > I've got a test server with 8Gb RAM > setup guest with rss.hard=90000 rss.soft=40000 > now run > stress --cpu 4 --vm 8 --vm-bytes 50M > Got oom-killer on host killing applicatioin on not guest but on host. > How to avoid this? you can avoid that by making host processes immune to the OOM killer, or by raising the badness_bias of the guests above any host vm usage, or disable overcommit completely > I've tring to setup vm.overcommit_memory=2 which doesen't help probably because you left the overcommit_ratio untouched, but you want to set this to 0 too > The only option seems to be > vm.oom_kill_allocating_task = 1 this is another way to address this specific case, but it might not be the best for the entire system > Is it a right way to do it? the OOM 'badness' which is the criterion used to choose the 'victim' is calculated like this: 1) total_vm of a process (system wide) plus 2) the badness_bias (if in a guest, default is 0) plus 3) the difference between rss_curr and rss_soft this is how it is calculated right now, with one exception, if there is a swapoff process running, it gets full score :) we might add another 'difference' based on the vm settings or some kind of multiplicative factor to that (if you like to test it, let me know) HTH, Herbert > -- > -- > Michael