Re: [libvirt] [PATCH] libxl: Add support for max_grant_frame setting

On 3/5/19 3:17 AM, Daniel P. Berrangé wrote: > On Mon, Mar 04, 2019 at 04:00:01PM -0700, Jim Fehlig wrote: > > Xen 4.10 introduced the max_grant_frames xl config setting, which > > can be set globally in xl.conf(5) or per-domain in xl.cfg(5). > > max_grant_frames specifies the maximum number of grant frames the > > domain is allowed to have, which in turn controls the number of > > pages the domain can share. > > Does the grant frame value have any impact on the live migration > compatibility ? ie if both source and dest host are required to > have identical grant frame values, then it is preferrable to /not/ > have this as a host tunable, but only as XML. You generally don't > want anything affecting mig compatibility in host level configs. Thanks for the reminder. Yes, grant frame value could have an affect on migration. I didn't put much thought into it since Xen has a similar concept in their host level config. Difference is, they also support the setting in their per-domain config. So I'm back to figuring out how to model this in XML https://www.redhat.com/archives/libvir-list/2019-February/msg01218.html Your opinion would be much appreciated! Thus far my preferred option is the last one described in that thread https://www.redhat.com/archives/libvir-list/2019-March/msg00124.html