| Message ID | 20240711120915.310243-1-f.ebner@proxmox.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | backup: allow specifying minimum cluster size | expand |
On 11.07.24 15:09, Fiona Ebner wrote: > Discussion for v2: > https://lore.kernel.org/qemu-devel/20240528120114.344416-1-f.ebner@proxmox.com/ > > Changes in v3: > * Pass min_cluster_size option directly without checking > has_min_cluster_size, because the default is 0 anyways. > * Calculate maximum of passed-in argument and default once at the > beginning of block_copy_calculate_cluster_size() > * Update warning message to reflect actual value used > * Do not leak qdict in error case > * Use PRI{i,u}64 macros > > Discussion for v1: > https://lore.kernel.org/qemu-devel/20240308155158.830258-1-f.ebner@proxmox.com/ > - > Changes in v2: > * Use 'size' type in QAPI. > * Remove option in cbw_parse_options(), i.e. before parsing generic > blockdev options. > * Reword commit messages hoping to describe the issue in a more > straight-forward way. > > In the context of backup fleecing, discarding the source will not work > when the fleecing image has a larger granularity than the one used for > block-copy operations (can happen if the backup target has smaller > cluster size), because cbw_co_pdiscard_snapshot() will align down the > discard requests and thus effectively ignore then. > > To make @discard-source work in such a scenario, allow specifying the > minimum cluster size used for block-copy operations and thus in > particular also the granularity for discard requests to the source. > > Fiona Ebner (2): > copy-before-write: allow specifying minimum cluster size > backup: add minimum cluster size to performance options > > block/backup.c | 2 +- > block/block-copy.c | 36 ++++++++++++++++++++++++++---------- > block/copy-before-write.c | 14 +++++++++++++- > block/copy-before-write.h | 1 + > blockdev.c | 3 +++ > include/block/block-copy.h | 1 + > qapi/block-core.json | 17 ++++++++++++++--- > 7 files changed, 59 insertions(+), 15 deletions(-) > Thanks, applied to my block branch.
Discussion for v2: https://lore.kernel.org/qemu-devel/20240528120114.344416-1-f.ebner@proxmox.com/ Changes in v3: * Pass min_cluster_size option directly without checking has_min_cluster_size, because the default is 0 anyways. * Calculate maximum of passed-in argument and default once at the beginning of block_copy_calculate_cluster_size() * Update warning message to reflect actual value used * Do not leak qdict in error case * Use PRI{i,u}64 macros Discussion for v1: https://lore.kernel.org/qemu-devel/20240308155158.830258-1-f.ebner@proxmox.com/ - Changes in v2: * Use 'size' type in QAPI. * Remove option in cbw_parse_options(), i.e. before parsing generic blockdev options. * Reword commit messages hoping to describe the issue in a more straight-forward way. In the context of backup fleecing, discarding the source will not work when the fleecing image has a larger granularity than the one used for block-copy operations (can happen if the backup target has smaller cluster size), because cbw_co_pdiscard_snapshot() will align down the discard requests and thus effectively ignore then. To make @discard-source work in such a scenario, allow specifying the minimum cluster size used for block-copy operations and thus in particular also the granularity for discard requests to the source. Fiona Ebner (2): copy-before-write: allow specifying minimum cluster size backup: add minimum cluster size to performance options block/backup.c | 2 +- block/block-copy.c | 36 ++++++++++++++++++++++++++---------- block/copy-before-write.c | 14 +++++++++++++- block/copy-before-write.h | 1 + blockdev.c | 3 +++ include/block/block-copy.h | 1 + qapi/block-core.json | 17 ++++++++++++++--- 7 files changed, 59 insertions(+), 15 deletions(-)