Thanks a lot for your confirmation, Marcus. I'll create a review request unless anyone has an objection.
Thanks Alex Ough On Tue, Nov 12, 2013 at 3:37 PM, Marcus Sorensen <shadow...@gmail.com>wrote: > I have done parallel KVM migrations without issue, it's "supposed to > work". Really I think it's in the same boat as parallel start/stop. It > should work, but the config option is there just in case. I think we > should add it. > > On Thu, Oct 3, 2013 at 11:41 AM, Chip Childers > <chip.child...@sungard.com> wrote: > > On Thu, Oct 03, 2013 at 11:44:46AM -0500, Alex Ough wrote: > >> I'm not sure what else commands 'MigrateCommand' actually execute in > >> addition to 'Start/Stop/CopyCommand', but can we include > 'MigrateCommand' > >> if it consists of only those 3 commands? > >> > >> Thanks > >> Alex Ough > > > > In the case of VMware, the migrate command is executed via the > > MigrateVMTask that's part of the VMware SDK (see > > vmware-base/src/com/cloud/hypervisor/vmware/mo/VirtualMachineMO.java). > > > > For VMware, I know that vCenter will queue and process concurrent > > requests for migrations. Specifically, it will throttle the migrations > > happening, based on it's internal concurrency constraints, but the task > > queue will still accept more connections. Obviously the risk are the > > VMware layer tasks timing out if it takes too long for the task queue to > > complete. > > > > As for XenServer, it's happening in what appears to be a similar way > > (although the source host is the target for the migration API call). > > > > Check > > > plugins/hypervisors/xen/src/com/cloud/hypervisor/xen/resource/CitrixResourceBase.java. > > > > I'm not familiar enough with XenServer's concurrency model for > > migrations. Any experts know the answer to if it can handle concurrency > > in a stable way? > > > > With KVM, it's obviously executing via the agent. Similarly to > > XenServer, I'm not familiar enough to know about concurrent operations. > > > > So do the HV experts on the list have any opinions about XenServer and > > KVM migration concurrency? > > > > -chip > > > > > >
