On 08/02/2010, at 22.50, Richard Elling wrote: >> >> r...@vmstor01:/# zpool list >> NAME SIZE ALLOC FREE CAP DEDUP HEALTH ALTROOT >> dataPool 9.94G 4.89G 5.04G 49% 1.00x ONLINE - >> >> Now here's what I don't get, why does it say the poo sizel is 9.94G when >> it's made up of 2 x raidz2 consisting of 1G volumes, it should only be 6G >> which df -h also reports correctly. > > No, zpool displays the available pool space. df -h displays something else > entirely. > If you have 10 1GB vdevs, then the total available pool space is 10GB. From > the > zpool(1m) man page: > ... > size > Total size of the storage pool. > > These space usage properties report actual physical space > available to the storage pool. The physical space can be > different from the total amount of space that any contained > datasets can actually use. The amount of space used in a > raidz configuration depends on the characteristics of the > data being written. In addition, ZFS reserves some space for > internal accounting that the zfs(1M) command takes into > account, but the zpool command does not. For non-full pools > of a reasonable size, these effects should be invisible. For > small pools, or pools that are close to being completely > full, these discrepancies may become more noticeable. > ... > > -- richard
Ok thanks I know that the amount of used space will vary, but what's the usefulness of the total size when ie in my pool above 4 x 1G (roughly, depending on recordsize) are reserved for parity, it's not like it's useable for anything else :) I just don't see the point when it's a raidz or raidz2 pool, but I guess I am missing something here. Cheers, - Lasse _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
