RAID10 and table layout
IDS: 7.30.uc7 OS: HPUX 10.20 I've just received word that I'll be able to implement striping / mirroring for my Informix system; total database size is about 25G. I'm looking at 3 9G drives and ?? 4G drives on a mirror. Any ideas, comments, generalizations? I'm a bit new at this, as we've always used singelton drives ( 2G / 4G ). Any recommended reading? Thanks in advance John Carlson Informix DBA WHSmith USA
The best way to do this is to mirror the drives themselves one-to-one and in that the mirrored pairs have to be the same drive. I'd suggest getting 12 4GB drives to create 6 mirrored pairs of matched drives (different manufacturing lots on each side of the pair for safety). Then you can tape 2 pairs for rootdbs, logs, and low activity tables and stripe the remaining 4 pairs for performance giving 16GB of striped space. Just one layout of course. Remember "Wider is better" a wider stripe (more spindles) will outperform a narrower one made up larger faster drives. Art S. Kagel "Carlson@WHSmith" wrote: > > IDS: 7.30.uc7 > OS: HPUX 10.20 > > I've just received word that I'll be able to implement striping / > mirroring for my Informix system; total database size is about 25G. I'm > looking at 3 9G drives and ?? 4G drives on a mirror. Any ideas, > comments, generalizations? I'm a bit new at this, as we've always used > singelton drives ( 2G / 4G ). Any recommended reading? > > Thanks in advance > John Carlson > Informix DBA > WHSmith USA
"Carlson@WHSmith" wrote: > > IDS: 7.30.uc7 > OS: HPUX 10.20 > > I've just received word that I'll be able to implement striping / > mirroring for my Informix system; total database size is about 25G. I'm > looking at 3 9G drives and ?? 4G drives on a mirror. Any ideas, > comments, generalizations? I'm a bit new at this, as we've always used > singelton drives ( 2G / 4G ). Any recommended reading? > For HP-UX you may be interested in the AutoRaid product. This will do all the work for you. You create logical LUNs which will be created as RAID 1/0 until it can no longer keep all data in 1/0 at which point infrequently used data will be moved to RAID 5. (This is a handy feature for creating allocating temporary disc space for reorganisation work. Once the LUN is removed the data will be returned to RAID 1/0.) If you're using LVM too you can then stripe across the logical LUNs making (what we call) a chequered logical volume. We have a lot a success with the 12H AutoRaids. They are also fully redundant with 3 power supplies, 3 fans, 2 controllers, and 12 discs which can (I believe) now be 4G or 9G discs. Discs can be removed and replaced at any time. (Though don't necessarily expect performance to be that good, one of our customers did this in their busy hour and checkpoints increased five-fold). Surprisingly for HP they're not frantically expensive either. Dominic -- Dominic Binks/Systems Engineer/Logica-Aldiscon 400 Park Avenue/Aztec West/Bristol/BS32 4TR/United Kingdom Tel: +44 1454 614455/Fax: +44 1454 620527/Mobile: +44 498 693964 E-mail: dominic.binks@aethos.co.uk