On 01/10/2018 17:48, George Dunlap wrote: > On 10/01/2018 04:40 PM, Andrew Cooper wrote: >> On 01/10/18 16:35, Wei Liu wrote: >>> On Mon, Oct 01, 2018 at 04:19:07PM +0100, George Dunlap wrote: >>>> On 10/01/2018 04:17 PM, Wei Liu wrote: >>>>> On Mon, Oct 01, 2018 at 09:10:25AM -0600, Jan Beulich wrote: >>>>>>>>> On 01.10.18 at 16:33, <wei.l...@citrix.com> wrote: >>>>>>> On Mon, Oct 01, 2018 at 03:04:02AM -0600, Jan Beulich wrote: >>>>>>>>>>> On 30.09.18 at 23:59, <osstest-ad...@xenproject.org> wrote: >>>>>>>>> flight 128240 xen-unstable real [real] >>>>>>>>> http://logs.test-lab.xenproject.org/osstest/logs/128240/ >>>>>>>>> >>>>>>>>> Regressions :-( >>>>>>>>> >>>>>>>>> Tests which did not succeed and are blocking, >>>>>>>>> including tests which could not be run: >>>>>>>>> test-amd64-amd64-migrupgrade 22 guest-migrate/src_host/dst_host fail >>>>>>>>> REGR. vs. >>>>>>> 128084 >>>>>>>> At the first glance >>>>>>>> >>>>>>>> libxl: error: libxl_sched.c:232:sched_credit_domain_set: Domain >>>>>>>> 1:Getting >>>>>>> domain sched credit: Invalid argument >>>>>>>> libxl: error: libxl_create.c:1275:domcreate_rebuild_done: Domain >>>>>>>> 1:cannot >>>>>>> (re-)build domain: -3 >>>>>>>> might indicate a problem resulting from the switch to credit2 as the >>>>>>>> default >>>>>>>> scheduler. But "first glance" here really means what it says - I >>>>>>>> didn't look >>>>>>>> (yet) at what exactly libxl tries to do there, in the hope that others >>>>>>>> may >>>>>>>> know without much digging. >>>>>>> I think this is due to toolstack trying to set the same scheduler >>>>>>> parameters for the newly created guest. >>>>>>> >>>>>>> But in this test, the destination host is using a different scheduler >>>>>>> from the source host. Asking for credit scheduler on a credit2 host is >>>>>>> wrong. >>>>>>> >>>>>>> The relevant snippet in guest cfg (JSON) is: >>>>>>> >>>>>>> "sched_params": { >>>>>>> "sched": "credit", >>>>>>> "weight": 256, >>>>>>> "cap": 0 >>>>>>> }, >>>>>>> >>>>>>> I can't think of a method to fix it off the top of my head though. >>>>>> So is this something that was specified in the original config? Or >>>>>> is it just the current value which gets read and an attempt made >>>>>> to re-install. If there was no explicit setting in the guest config, >>>>>> shouldn't such a "default" setting be retained by not transferring >>>>>> any scheduler specifics during migration? >>>>>> >>>>> No setting in guest cfg. Those values are extracted from the hypervisor. >>>>> I think we may be able to not send default values to the remote end. >>>> Wait, the migration code reads the scheduler parameters -- even if these >>>> have not been explicitly set by the admin -- and sends them along with >>>> the migration stream? And if the remote scheduler is different, the >>>> migration fails? >>>> >>>> That's not so good. :-) >>> But one can argue that the guest is specific configured that way so it's >>> parameters should be preserved. We normally analyse things on a case by >>> case basis. >> >> If there isn't an obvious fix, then the switch of default scheduler >> needs reverting until there is a fix present. This is currently >> blocking master. > > Agreed. I'd argue for ignoring failures to set scheduler parameters on > migrate, on the grounds that this will be less risk to the project as a > whole than reverting credit2 again. But either way we should do > something quickly.
We should ignore a mismatch of the scheduler. Failures when setting parameters for a matching scheduler should not be ignored IMO. Juergen _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
