On Wed, March 10, 2010 12:49, Matt wrote: > So I'm working up my SAN build, and I want to make sure it's going to > behave the way I expect when I go to expand it. > > Currently I'm running 10 - 500GB Seagate Barracuda ES.2 drives as two > drive mirrors added to my tank pool. > > I'm going to be using this for virtual machine storage, and have created > fixed size disks (around 200GB per file). > > If I'm reading the documentation correctly, if I add spindles to my drive > array (say 10 more drives) even though the data files on the disks won't > change in size, the data will eventually migrate to all spindles as it is > changed and written out, thus improving performance. Is this correct?
I think so; though you're using non-ZFS terminology which hence isn't absolutely precise. Let me rephrase it: If you add more mirror vdevs to your pool named "tank", that space will become instantly available to things that draw on that pool (filesystems, zvols, and I forget what else). When new data has to be written, there will be a preference for it going to less-full vdevs in the pool; so as data is rewritten, usage will gradually even out across the vdevs in the pool. Having the data across more spindles can, obviously, potentially increase performance, depending on what the existing limiting factors are. So, if that says about the same thing you said, then the answer to your question is "yes". -- David Dyer-Bennet, d...@dd-b.net; http://dd-b.net/ Snapshots: http://dd-b.net/dd-b/SnapshotAlbum/data/ Photos: http://dd-b.net/photography/gallery/ Dragaera: http://dragaera.info _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
