Q. When I boot from a dynamic Virtual Hard Disk (VHD), the VHD is pre-expanded to its maximum size and then shrinks again. Why?

A. A fixed VHD is recommended for best performance, especially in production environments. A dynamic VHD (which expands as data is written) could cause problems for the OS if the partition containing the VHD has no free space and the dynamic VHD attempts to grow. To avoid this situation, a VHD that is being natively booted is pre-expanded at boot time and then shrunk when the OS shuts down.

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