forum user report slow qcow2 volume create with preallocated metadatas http://forum.proxmox.com/threads/17471-GlusterFS-amp-Proxmox-Future-amp-QCOW2-Issues (note that I can't reproduce it with qemu 1.7) But redhat bugzilla have an entry about possible problem with volume is create through mount point. https://bugzilla.redhat.com/show_bug.cgi?id=895830 So,It's better to manage it through gluster block driver directly. (We need only the mount point to create directory and list images files) Signed-off-by: Alexandre Derumier <aderumier@odiso.com>