How To Distribute I/O over a limited # of disks.

From: S Green <twogreens_at_sprynet.com>
Date: Sun, 10 May 1998 15:57:07 -0500
Message-ID: <6j543n$6is$1@juliana.sprynet.com>

I am configuring an OLTP application, using Oracle 7.3.2 on a Sun with Solaris 2.6. We only have 8 disks. In 3 months we will be buying another disk tray and several more disks. For now, I want the best compromise configuration. The application is very transactional, so RAID 5 not appropriate. We have an unattended 7x24 application. I really want to be able to ride through a disk failure automatically, so Raid 1 or RAID 0/1 seems best.

I want to mirror the system disk using RAID 1. That leave 6 disks for the data base. The redo logs, being sequential and requiring redundancy, would work well with RAID 1. That leaves 4 disks for everything else. Any suggestions. Yes, I know that 7 disks is suggested as a minimal configuration.

Here is my highly compromised solution: disk0, mirrored (highly loaded, but it has a separate internal controller!)

   UNIX
   oracle product
   INDEXES
  control file 1

disk1, mirrored

    SYSTEM
    REDO LOGS 1,2, 3….
    control file 2

disk 2, mirrored

RBS, RBS_2
ARCHIVE LOG FILES (assuming we run in archive mode). control file 3

disk 3, mirrored

   DATA
  TEMP
   control file 4

Please offer suggestions, except the obvious- buying more disks :).

TIA, Scott Received on Sun May 10 1998 - 15:57:07 CDT