How to migrate un-migratable VMs?
Hi, Some VMs are doing high guest-memory writes (mainly files and mail servers, but not only), so migrations are reproductively failing. I found some info here : https://bugzilla.redhat.com/show_bug.cgi?id=919201 that confirm what I was fearing. This BZ is aging from dinosaurs times, so I was wondering now we're in the 3.6.x age and 4.x coming, are there advices one may give to migrate those verbose VMs? I guess increasing the allowed page memory is not a correct answer as it will fill as before. Any thoughts? -- Nicolas ECARNOT
----- Original Message -----
From: "Nicolas Ecarnot" <nicolas@ecarnot.net> To: users@ovirt.org Sent: Monday, May 16, 2016 12:32:31 PM Subject: [ovirt-users] How to migrate un-migratable VMs?
Hi,
Some VMs are doing high guest-memory writes (mainly files and mail servers, but not only), so migrations are reproductively failing. I found some info here : https://bugzilla.redhat.com/show_bug.cgi?id=919201 that confirm what I was fearing.
This BZ is aging from dinosaurs times, so I was wondering now we're in the 3.6.x age and 4.x coming, are there advices one may give to migrate those verbose VMs?
hi, in 4.0 we have been working hard to enhance the migrations: https://bugzilla.redhat.com/1252426 in 4.0 it should: - make use of the bandwidth much better - have some policies which will be managing the downtime and you will be able to pick per cluster and override per VM - have ability to write custom hooks inside the guest which will be notified that now the VM is migrating (if you have some custom logic you want to do) ...and some more enhancements Long story short, in 4.0 it your VMs should migrate much more smooth
I guess increasing the allowed page memory is not a correct answer as it will fill as before.
Any thoughts?
-- Nicolas ECARNOT _______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
Le 17/05/2016 13:29, Tomas Jelinek a écrit :
in 4.0 we have been working hard to enhance the migrations: https://bugzilla.redhat.com/1252426
in 4.0 it should: - make use of the bandwidth much better - have some policies which will be managing the downtime and you will be able to pick per cluster and override per VM - have ability to write custom hooks inside the guest which will be notified that now the VM is migrating (if you have some custom logic you want to do)
...and some more enhancements
Long story short, in 4.0 it your VMs should migrate much more smooth
OK Tomas, thank you for your answer. But I don't understand how that would help in the following problem:
I guess increasing the allowed page memory is not a correct answer as it will fill as before.
-- Nicolas ECARNOT
On 17 May 2016, at 20:32, Nicolas Ecarnot <nicolas@ecarnot.net> wrote:
Le 17/05/2016 13:29, Tomas Jelinek a écrit :
in 4.0 we have been working hard to enhance the migrations: https://bugzilla.redhat.com/1252426
in 4.0 it should: - make use of the bandwidth much better - have some policies which will be managing the downtime and you will be able to pick per cluster and override per VM - have ability to write custom hooks inside the guest which will be notified that now the VM is migrating (if you have some custom logic you want to do)
...and some more enhancements
Long story short, in 4.0 it your VMs should migrate much more smooth
OK Tomas, thank you for your answer. But I don't understand how that would help in the following problem:
The situation mentioned it the bug will not happen anymore. The bandwidth and larger downtime would make sure that migration converges
I guess increasing the allowed page memory is not a correct answer as it will fill as before.
-- Nicolas ECARNOT _______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
participants (3)
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Michal Skrivanek -
Nicolas Ecarnot -
Tomas Jelinek