Just a quick question. If I create a raidz pool but then later find that I need more space I can add another raidz set to the pool but what happens to data already in the pool? Does a relayout occur or does zfs work towards balancing I/O to the pool across the 2 raidz sets only as new data is written? Also, is it possible to explicitly request a relayout; for example can I convert a raidz1 pool to a raidz2 pool? This message posted from opensolaris.org
> Just a quick question. If I create a raidz pool but then later find > that I need more space I can add another raidz set to the pool but > what happens to data already in the pool? Does a relayout occur or > does zfs work towards balancing I/O to the pool across the 2 raidz > sets only as new data is written?Technically, raidz describes a vdev in a pool, not a pool itself. So yes, you can add another raidz to the pool. New data is striped across both components, but weighted to the empty one to try to balance things out a bit over time. No relayout occurs.> Also, is it possible to explicitly request a relayout; for example can > I convert a raidz1 pool to a raidz2 pool?Not today. My assumption is that other items (like zpool shrink/evacuation) are being targeted as a higher priority. -- Darren Dunham ddunham at taos.com Senior Technical Consultant TAOS http://www.taos.com/ Got some Dr Pepper? San Francisco, CA bay area < This line left intentionally blank to confuse you. >
On 31 May, 2007 - Vic Engle sent me these 0,6K bytes:> Just a quick question. If I create a raidz pool but then later find > that I need more space I can add another raidz set to the pool but > what happens to data already in the pool? Does a relayout occur or > does zfs work towards balancing I/O to the pool across the 2 raidz > sets only as new data is written?If you have a raidz of say 500G, filled with 300G of data.. then you add another raidz of 500G and start writing.. ZFS will put more data on the second raidz thing to even out the distribution..> Also, is it possible to explicitly request a relayout; for example can > I convert a raidz1 pool to a raidz2 pool?Currently no. /Tomas -- Tomas ?gren, stric at acc.umu.se, http://www.acc.umu.se/~stric/ |- Student at Computing Science, University of Ume? `- Sysadmin at {cs,acc}.umu.se