diff options
Diffstat (limited to 'cddl/contrib/opensolaris/lib/libzfs_core/common/libzfs_core.c')
-rw-r--r-- | cddl/contrib/opensolaris/lib/libzfs_core/common/libzfs_core.c | 22 |
1 files changed, 17 insertions, 5 deletions
diff --git a/cddl/contrib/opensolaris/lib/libzfs_core/common/libzfs_core.c b/cddl/contrib/opensolaris/lib/libzfs_core/common/libzfs_core.c index 52bd580..5ba660d 100644 --- a/cddl/contrib/opensolaris/lib/libzfs_core/common/libzfs_core.c +++ b/cddl/contrib/opensolaris/lib/libzfs_core/common/libzfs_core.c @@ -20,7 +20,7 @@ */ /* - * Copyright (c) 2013 by Delphix. All rights reserved. + * Copyright (c) 2012, 2014 by Delphix. All rights reserved. * Copyright (c) 2013 Steven Hartland. All rights reserved. */ @@ -532,18 +532,30 @@ lzc_send(const char *snapname, const char *from, int fd, } /* - * If fromsnap is NULL, a full (non-incremental) stream will be estimated. + * "from" can be NULL, a snapshot, or a bookmark. + * + * If from is NULL, a full (non-incremental) stream will be estimated. This + * is calculated very efficiently. + * + * If from is a snapshot, lzc_send_space uses the deadlists attached to + * each snapshot to efficiently estimate the stream size. + * + * If from is a bookmark, the indirect blocks in the destination snapshot + * are traversed, looking for blocks with a birth time since the creation TXG of + * the snapshot this bookmark was created from. This will result in + * significantly more I/O and be less efficient than a send space estimation on + * an equivalent snapshot. */ int -lzc_send_space(const char *snapname, const char *fromsnap, uint64_t *spacep) +lzc_send_space(const char *snapname, const char *from, uint64_t *spacep) { nvlist_t *args; nvlist_t *result; int err; args = fnvlist_alloc(); - if (fromsnap != NULL) - fnvlist_add_string(args, "fromsnap", fromsnap); + if (from != NULL) + fnvlist_add_string(args, "from", from); err = lzc_ioctl(ZFS_IOC_SEND_SPACE, snapname, args, &result); nvlist_free(args); if (err == 0) |