Hi Luc Normally, the primary factor isnt how many volumes you have. Its rather dependent on how many physical volumes you have your database on. Physical volumes can be either disks in your machine or LUN:s assigned from a central disk. If you're using SAN attached LUN:s, you should not count the physical disks you're using in your SAN disk rather the number of LUN:s, as each LUN:s has it's own write/read queue.
According to what I've seen, using between 8-12 database volumes gives a good performance. You should however spread them across at least 4-6 disks, preferable 8-12 disks for optimum performance. When it comes to RAID I would recommend using RAID-1 or RAID 0+1. RAID-5 normally gives a slight performance hit during write operations due to the RAID-5 parity. Remember that mirroring your database using hardware or operating system will not entirely protect your database against faults. The only mirroing solution that protects you against for example partial writes is using the built-in database and log mirroring facility within TSM. I would not recommend you to use only one physical disk with one database volume. That would probably decrease your database performance. Best Regards Daniel Sparrman ----------------------------------- Daniel Sparrman Chef Utveckling & Drift Exist i Stockholm AB Propellerv�gen 6B 183 62 T�BY V�xel: 08 - 754 98 00 Mobil: 070 - 399 27 51 Luc Beaudoin <[EMAIL PROTECTED]> Sent by: "ADSM: Dist Stor Manager" <[email protected]> 2005-01-20 17:20 Please respond to "ADSM: Dist Stor Manager" <[email protected]> To [email protected] cc Subject TSM DB Volumes Hi all I'm reading on how to delete DB volume ... and I'm a bit confuse ... In the Admin book .. they take 4 small volumes and move them to one big one ... Is there a best practice or advantages to have 1 big volume or 5 small ones ???? In my case I have 4 volumes of 4GB and 1 of 20GB .. I would like to put them al together in one big volume .. Any ideas ?? thanks again Luc
