Re: [libvirt] [PATCH 1/2] rbd: Add wiping RBD volumes by using rbd_discard() or rbd_write()

On 12/23/2015 10:06 AM, Wido den Hollander wrote: > This allows user to use the volume wiping functionality of the libvirt > storage driver. > > This patch also adds a new wiping algorithm VIR_STORAGE_VOL_WIPE_ALG_DISCARD > > By default the VIR_STORAGE_VOL_WIPE_ALG_ZERO algorithm is used and with > RBD this will called rbd_write() in chunks of the underlying object size > to completely zero out the volume. > > With VIR_STORAGE_VOL_WIPE_ALG_DISCARD it will call rbd_discard() in the > same object size chunks which will trim/discard all underlying RADOS objects > in the Ceph cluster. > > Signed-off-by: Wido den Hollander <wido(a)widodh.nl&gt; > --- > include/libvirt/libvirt-storage.h | 4 + > src/storage/storage_backend_rbd.c | 155 +++++++++++++++++++++++++++++++++++++- > tools/virsh-volume.c | 2 +- > 3 files changed, 159 insertions(+), 2 deletions(-) > Found these buried in my todo list of things to look at from during the holiday break. I figure by bumping it'll bring it back into focus... "Semantically" speaking - this patch is a v2 of the original patch series... I'm still a bit conflicted whether to add a new option to Wipe or whether a new API should be developed. I see value in both options. Although perhaps thinking of this as "trim" and not "discard" could make it more palatable for wipe. As a new API, each backend driver could decide whether it supports the discard/trim option, but that's quite a bit more work (essentially mimic the Wipe functionality, but generate Trim).