Slow performance from converted VHDX to Qcow2


New Member
Oct 11, 2023
Morning All, we recently converted a vhdx to qcow2 using command - qemu-img convert -f vhdx -O qcow2 example.vhdx example.qcow2. Machine boots, however disk IO and speed shocking and also we could no longer run acronis backups. In addition, we can only boot if we use interface IDE, all other options fail with recovery screen. We then upgraded the "compat" version to 1.1 using qemu-img convert -f qcow2 -O qcow2 -o compat=1.1 example.hdd example-new.hdd and this solved backup issue and also dramatically improved machine response, however did not improve IO speeds. Does anyone have suggestions on how to change interface type during convert or after so that a different faster interface can be chosen thanks


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