Yes “VirtIO SCSI” is used but the hard disk itself is created as SATA and not SCSI. Why that?
Here a quote from Proxmox 7.1 roadmap:
VMs with SATA as disk bus may show issues when used with
io_uring
- For now this can be worked around by switching the disk’s
Async IO
mode to threads (for cache = >write back/through) or native (for cache = off, none or direct sync), respectively, in the Advanced >options of the disk edit dialogue.- Note that SATA is really not the best choice for a VM’s disk bus in general, rather use (VirtIO-) SCSI >for best performance and feature set. For Windows VirtIO support is available through the Windows >VirtIO Drivers