On maandag, september 2, 2002, at 11:26 , Daniel Sparrman wrote: > Hi > > The large disks you are talking about, are you meaning large as 36GB, > 72GB > an so on, or are you talking about LUN-sizes? >
Disk size, 72 GB or so.... > In a shark, you can have very large LUN:s, but they will consist of a > large number of smaller SSA-based hard drives. This means that you will > not have a performance impact on the disks. > I know, I also know that you will have performance impact on your disks. I noticed that especially the IBM ssa raid controller (4-P) gives very bad performance on any kind of raid. I don't have a shark, so I can't talk about it's raid controller. Having eg. both the db volumes and the logvolumes on the same raidgroup will for sure give you very bad performance on the disks. Also, I don't think it's a good idea to have a database (or log) spread across multiple partitions on the same raidgroup. TSM will try to do 'smart' load balancing, which will decrease performance in that case since the disks will have to do more seeks. --- Met vriendelijke groeten, Remco Post SARA - Stichting Academisch Rekencentrum Amsterdam http://www.sara.nl High Performance Computing Tel. +31 20 592 8008 Fax. +31 20 668 3167 PGP keys at http://home.sara.nl/~remco/keys.asc "I really didn't foresee the Internet. But then, neither did the computer industry. Not that that tells us very much of course - the computer industry didn't even foresee that the century was going to end." -- Douglas Adams
