On Wed, May 08, 2013 at 01:18:17PM +0800, yuxh wrote: > I have to consult you a qemu-img's problem. > > Is this reasonable to create a file which is larger than the > available size of the fs by qemu-img cmd ? > > When I use qemu-img create a file which is larger than the available > size of the fs, the creation is completed succesfully. > > However when I use this file in guest as a guest's disk, and write > beyond the size the host file can provides, the guest was paused by > qemu-kvm or libvirt and was in maybe a infinite circle where the > guest just can't be used except I detach the disk from guest or > destroy the guest.
You can change the ENOSPC policy with -drive werror=,rerror=. See the QEMU man page. The default behavior is to pause the guest so the host admin can free up or add space. Then the guest can be continued - this will retry the I/O. But you can also tell QEMU to pass the error through to the guest using the -drive werror=,rerror= options. Stefan