Il 08/10/2014 13:15, Alexandre DERUMIER ha scritto: > Hi, > > I'm currently planning to migrate our storage to ceph/rbd through qemu > drive-mirror > > and It seem that drive-mirror with rbd block driver, don't create a sparse > image. (all zeros are copied to the target rbd). > > Also note, that it's working fine with "qemu-img convert" , the rbd volume is > sparse after conversion. > > > Could it be related to the "bdrv_co_write_zeroes" missing features in > block/rbd.c ? > > (It's available in other block drivers (scsi,gluster,raw-aio) , and I don't > have this problem with theses block drivers).
Lack of bdrv_co_write_zeroes is why detect-zeroes does not work. Lack of bdrv_get_block_status is why sparse->sparse does not work without detect-zeroes. Paolo
