fn collect_zfs_spaces(timeout: Duration) -> Vec<(String, DiskMountMetrics)>Expand description
Collect space stats for every imported ZFS pool via zpool list -Hp.
ZFS statvfs is unsuitable for pool-level capacity: the kernel sets
f_blocks = (pool_avail + dataset.referenced_bytes) >> SPA_MINBLOCKSHIFT,
i.e. only the REFER column (space at this dataset level, not recursive),
not the pool total. For a pool with many child datasets this gives a
heavily under-counted figure. zpool list is the only authoritative
source for pool capacity, used, and free.
Mount-point information is looked up from /proc/mounts as a best-effort
annotation; the dataset with the fewest path components per pool is preferred.