Gitweb: http://git.fedorahosted.org/git/?p=lvm2.git;a=commitdiff;h=bd3ece0128926cc15... Commit: bd3ece0128926cc156b7fcb6409acc1a2afb16db Parent: eb7e206a73a4fae5b93ffcdf96640675f7a72a73 Author: Zdenek Kabelac zkabelac@redhat.com AuthorDate: Wed May 29 21:43:46 2013 +0200 Committer: Zdenek Kabelac zkabelac@redhat.com CommitterDate: Thu May 30 17:35:14 2013 +0200

lvcreate: reduce too large cow

Detect maximum usable size of snapshot COW device, and do not waste more space for such LV then needed. --- WHATS_NEW | 1 + tools/lvcreate.c | 18 ++++++++++++++++++ 2 files changed, 19 insertions(+), 0 deletions(-)

diff --git a/WHATS_NEW b/WHATS_NEW index c7eb82a..d757e2b 100644 --- a/WHATS_NEW +++ b/WHATS_NEW @@ -1,5 +1,6 @@ Version 2.02.99 - =================================== + Creation of snapshot takes at most 100% origin coverage. Add cow_max_extents() to calc extents for 100% origin coverage. For creation of snapshot require size for at least 3 chunks. Fix lvresize --use-policies of VALID but 100% full snapshot. diff --git a/tools/lvcreate.c b/tools/lvcreate.c index 7580155..497c474 100644 --- a/tools/lvcreate.c +++ b/tools/lvcreate.c @@ -241,6 +241,7 @@ static int _update_extents_params(struct volume_group *vg, struct logical_volume *origin = NULL; uint32_t size_rest; uint32_t stripesize_extents; + uint32_t extents;

if (lcp->size && !(lp->extents = extents_from_size(vg->cmd, lcp->size, @@ -299,6 +300,23 @@ static int _update_extents_params(struct volume_group *vg, break; }

+ if (lp->snapshot && lp->origin) { + if (!origin && !(origin = find_lv(vg, lp->origin))) { + log_error("Couldn't find origin volume '%s'.", + lp->origin); + return 0; + } + + extents = cow_max_extents(origin, lp->chunk_size); + + if (extents < lp->extents) { + log_print_unless_silent("Reducing COW size %s down to maximum usable size %s.", + display_size(vg->cmd, (uint64_t) vg->extent_size * lp->extents), + display_size(vg->cmd, (uint64_t) vg->extent_size * extents)); + lp->extents = extents; + } + } + if (!(stripesize_extents = lp->stripe_size / vg->extent_size)) stripesize_extents = 1;