- When you attach a Premium SSD v2 or Ultra disk created from snapshot to a running Virtual Machine while CompletionPercent property hasn't reached 100, the disk suffers performance impact. Specifically, if the disk has a 4k sector size, it may experience slower read. If the disk has a 512e sector size, it may experience slower read and write. To track the progress of this background copy process, see the the check disk status section of either the Azure [PowerShell sample](../articles/virtual-machines/scripts/virtual-machines-powershell-sample-create-managed-disk-from-snapshot.md#performance-impact---background-copy-process) or the [Azure CLI](../articles/virtual-machines/scripts/create-managed-disk-from-snapshot.md#performance-impact---background-copy-process).
0 commit comments