Am 24.07.2018 um 09:25 schrieb Dietmar Maurer: >> Am 23.07.2018 um 21:04 schrieb Alexandre DERUMIER: >>> Personally, I think that a vm could take all cpu usage, or memory, and >>> impact ceph cluster for other vms. >>> >>> we should give ceph some kind of (configurable) priority. >> >> Yes the problem is or might be. Most users will overcommit the cpu cores >> with VMs. So theoretically the kvm processes might eat ALL CPU cores. > > Really? I though we have a scheduler that give all processes a change to run. > >> But while running ceph on the same node this should NEVER happen. So my >> idea is to give cores exclusively to ceph. > > Why exclusively? A scheduler can prioritize specific processes.
I'm not sure how this influences latency - it will move the processes between cores and still fight against qemu. Even if the scheduler is fast enough you still have the NUMA problem. See for example: http://tracker.ceph.com/projects/ceph/wiki/Tuning_for_All_Flash_Deployments#Ceph-Storage-Node-NUMA-Tuning Greets, Stefan _______________________________________________ pve-devel mailing list pve-devel@pve.proxmox.com https://pve.proxmox.com/cgi-bin/mailman/listinfo/pve-devel
