Hello, @mark.fang !
Can I use spot VMs for bursting? Do I get max credits when the VM is created?
The B family (burstable) VMs which use credits for CPU performance provisioning are not supported when using Azure Spot Virtual Machines:
https://learn.microsoft.com/en-us/azure/virtual-machines/spot-vms#limitations
As an alternative, you might consider the storage optimized Lsv2-series which uses disk bursting. Your resource, either a VM or disk, will start with fully stocked credits in its own burst bucket:
https://learn.microsoft.com/en-us/azure/virtual-machines/disk-bursting#bursting-flow
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