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On Fri, 2023-10-06 at 09:04 +0200, Massimo Sgaravatto wrote:
> Thanks for your answer
> 
> I guess you are referring to the cpu_shares in the flavor quota [*]
> 
> Actually I never explicitly set a value of cpu_shares in the flavor ...
if you are seeing this for instance where its not explictly in the falvor then
this is form the old behavior where we set a default share value as flavor.vcpus *1000
in newer version of openstack we never set an implict value
https://github.com/openstack/nova/commit/f77a9fee5b736899ecc39d33e4f4e4012cee751cthis change is aviable in zed+
i know this has been backported downstream to wallaby so its possibel to do
i belive there was consern with upstream backporting do to cpu starvation
if you were hevialy using this funtionatlity. that is why it was not backported
upstream in the past but you could apply it too your own cloud.

> 
> 
> [*] https://docs.openstack.org/nova/yoga/admin/resource-limits.html
> 
> On Thu, Oct 5, 2023 at 9:17 PM <smooney at redhat.com> wrote:
> 
> > On Thu, 2023-10-05 at 16:53 +0200, Massimo Sgaravatto wrote:
> > > Dear all
> > > 
> > > We have recently updated openstack nova on some AlmaLinux9 compute nodes
> > > running Yoga from 1:25.2.0 to 1.25.2.1. After this operation some VMs
> > don't
> > > start anymore. In the log it is reported:
> > > 
> > > libvirt.libvirtError: invalid argument: shares \'57344\' must be in range
> > > [1, 10000]\n'}
> > > 
> > > libvirt version is 9.0.0-10.3
> > > 
> > > 
> > > A quick google search suggests that it is something related to cgroups
> > and
> > > it is fixed in libvirt >= 9.1 (which is not yet in the almalinux9 repos).
> > > Did I get it right ?
> > not quite
> > 
> > it is reated to cgroups but the cause is that in cgroups_v1 the maxvlaue
> > of shares
> > i.e. cpu_shares changed form make int to 10000 in cgroups_v2
> > so the issue is teh vm requested a cpu share value of 57344 which is not
> > vlaid on an OS
> > that is useing cgroups_v2 libvirt will not clamp the value nor will nova.
> > you have to change the volue in your flavor and resize the vm.
> > 
> > > 
> > > 
> > > 
> > > Thanks, Massimo
> > 
> >