It is possible to configure ZFS in the way you describe, but your performance will be limited by the older array.
All mirror writes have to be stored on both arrays before they are considered complete, so writes will be as slow as the slowest disk or array involved. ZFS does not currently consider performance in selecting a mirror side for reads, so half of the reads will run at the speed of the new array, half at the speed of the old array. If you need to use both types of arrays (20 To is a lot of space to give up!), consider creating two pools, one composed of newer arrays and one of older arrays, at least if your data is easily split into "fast" and "slow" sets (e.g. fresh data vs. archival, or database logs vs. infrequently-accessed tables). This message posted from opensolaris.org _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
