Dear Vinicius, This is an interesting issue indeed. I've opened a ticket to keep track of it:
http://dev.opennebula.org/issues/846 Regards, -Tino -- Constantino Vázquez Blanco | dsa-research.org/tinova Virtualization Technology Engineer / Researcher OpenNebula Toolkit | opennebula.org 2011/9/14 Vinícius Vielmo Cogo <[email protected]>: > Hello, > > We have one question/suggestion regarding the approach of the scheduler face > to an result of impossibility on resource allocation process. > > As the OpenNebula default matchmaking scheduler is an immediate lease > scheduler, it should always return the allocated resources or an error due > to it's impossibility. But, when the scheduler receives an expression which > turns to an impossible result, the VM remains in pending state indefinitely, > which is an approach related with best-effort schedulers. > > Specifically in our case, we want to deploy one Virtual Machine on each host > of our cloud (for security reasons) and we don't want to obtain all > information about the entire HostPool in each VM creation (scalability > reasons). > The problem arises when we achieve the entire set of hosts inside of our > requirements (e.g using "HOSTNAME != \"some-host\"" & "HOSTNAME != > \"another-host\"", etc), which means that don't exist other host to allocate > the Virtual Machine. > > This approach also can be considered one of the reasons that contributed for > other similar issues pointed on mailing list, as for example, on [one-users] > VM creation stuck in "pending" state thread, where the same problems could > be solved if the OpenNebula would changed the VM state to fail and logged > the appropriate output. > > We believe that there are at least two main possibilities to circumvent this > problem: > 1) Change the VM state to "fail" when an impossible result is achieved. > 2) Add a new state for the virtual machine to indicate when it achieve an > impossible result (for example, an impossible state). > > We would like to know your opinion about this approach, if it's possible to > modify the OpenNebula scheduler in those terms and/or if you could indicate > other ways to avoid this pending issue. > > Thank you in advance. > Vinicius Vielmo Cogo > _______________________________________________ > Users mailing list > [email protected] > http://lists.opennebula.org/listinfo.cgi/users-opennebula.org > > _______________________________________________ Users mailing list [email protected] http://lists.opennebula.org/listinfo.cgi/users-opennebula.org
