On 9/16/12 10:40 AM, "Richard Elling" <richard.ell...@gmail.com> wrote:
>With a zvol of 8K blocksize, 4K sector disks, and raidz you will get 12K >(data >plus parity) written for every block, regardless of how many disks are in >the set. >There will also be some metadata overhead, but I don't know of a metadata >sizing formula for the general case. > >So the bad news is, 4K sector disks with small blocksize zvols tend to >have space utilization more like mirroring. The good news is that >performance >is also more like mirroring. > -- richard Ok, that makes sense. And since there's no way to change the blocksize of a zvol after creation (AFAIK) I can either live with the size, find 3TB drives with 512byte sectors (I think Seagate Constellations would work) and do yet another send/receive, or create a new zvol with a larger blocksize and copy the files from one zvol to the other. (Leaning toward option 3 because the files are mostly largish graphics files and the like.) Thanks for the help! -- Dave Pooser Manager of Information Services Alford Media http://www.alfordmedia.com _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
