Right now, vmsize is inside the package (cspkg) that ships to AppFabric. This is a solution that is part of the assembly / packaging. So, to change it, you need to change VMSize, create the package, and then [re] deploy.
If you have a running system, you can avoid downtime using VIP Swap. He will basically get up another AT [s] in the intermediate slot with the new virtual machine size and then switch to it.
So, there are more moving parts involved, but you can still change it with little or no impact.
bryanmac
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