On Tue, Jun 14, 2011 at 10:09 PM, Ding Honghui <ding_hong...@vobile.cn> wrote: > I expect to have 14*931/1024=12.7TB zpool space, but actually, it only have > 12.6TB zpool space: > # zpool list > NAME SIZE USED AVAIL CAP HEALTH ALTROOT > datapool 12.6T 9.96T 2.66T 78% ONLINE - > # > > And I expect the zfs usable space is 12*931/1024=10.91TB, but actually, it > only have 10.58TB zfs space. > > Can any one explain where the disk space goes?
I generally like to start with the number of guaranteed sectors on a drive rather than worrying about converting "vendor math". :) Then I do $NSEC/2097152 to get GB (assuming 512-byte sectors). ZFS reserves 1/64 of the pool size to protect copy-on-write as the pool approaches being full. After you make your usable space calculation, subtract 1/64 of that (total*.016) and that should be very close to the available space reported by 'zfs list'. Eric _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
