On Fri, Jul 18, 2014 at 6:58 PM, Chris Friesen <chris.frie...@windriver.com> wrote: > Hi, > > I've recently run up against an interesting issue where I had a number of > guests running and when I started doing heavy disk I/O on a virtio disk > (backed via ceph rbd) the memory consumption spiked and triggered the > OOM-killer. > > I want to reserve some memory for I/O, but I don't know how much it can use > in the worst-case. > > Is there a limit on the number of in-flight I/O operations? (Preferably as > a configurable option, but even hard-coded would be good to know as well.) > > Thanks, > Chris >
Hi, are you using per-vm cgroups or it was happened on bare system? Ceph backend have writeback cache setting, may be you hitting it but it must be set enormously large then.
