I think this is related to : https://www.redhat.com/archives/vfio-users/2016-April/msg00032.html
----- Mail original ----- De: "Wolfgang Bumiller" <[email protected]> À: "Gilou" <[email protected]> Cc: "proxmoxve" <[email protected]>, "aderumier" <[email protected]> Envoyé: Mercredi 11 Mai 2016 12:36:28 Objet: Re: [PVE-User] Regression on virtio-net ? (Was: Re: Proxmox VE 4.2 released!) On Tue, May 10, 2016 at 01:37:27PM +0200, Gilou wrote: > Le 09/05/2016 15:33, Alexandre DERUMIER a écrit : > > For v6 (skylake), I think they are new feature implementation in kvm > > http://www.gossamer-threads.com/lists/linux/kernel/2267259 > > > > for v4, I don't see any recent change > > > > > > You can reproduce with both v4 and v6 ? > > Yes, though again m y lab is unavailable for this, so I can't do it > "again". But it was a 4xxx & 6xxx that showed the issue in the first place. > > I just tried on a 4xxx I have on my laptop, it has the issue (using > kvm/ubuntu rather than Proxmox, but still) After bisecting it seems this commit is the issue: https://github.com/torvalds/linux/commit/aca6ff29c4063a8d467cdee241e6b3bf7dc4a171 Can you try loading the kvm module with these options: halt_poll_ns_grow=0 halt_poll_ns_shrink=0 (/etc/modprobe.d + reboot, or grub boot commandline (with the `kvm.` prefix to the options), or just: # rmmod kvm-intel # rmmod kvm # modprobe kvm halt_poll_ns_grow=0 halt_poll_ns_shrink=0 # modprobe kvm-intel ) This should revert the behavior of this commit. In my test VM this commit bumps my load from 60% to 100% with the same 'perf' output you had, and setting these options revert it back to normal. _______________________________________________ pve-user mailing list [email protected] http://pve.proxmox.com/cgi-bin/mailman/listinfo/pve-user
