[Qemu-devel] qmp drive-mirror vs qemu-img convert , drive-mirror really slow

[Alexandre DERUMIER]

Hi list,

I'm doing some speed benchmark between

drive-mirror vs qemu-img convert ,

and drive-mirror seem to be a lot slower.


test:

convert 1 32GB qcow2 file to raw file, local storage (6 disk 15k in raid10 + 
raid BBU cache)

time result:

qemu-img : 30sec
drive-mirror (vm is paused, no writes) : 5min


Any idea why drive-mirror is so slow ? (maybe does it use directsync when 
mirroring ?)

I think both should have around same speed ?


Best Regards,

Derumier Alexandre