02-27-2013
I assume by striped LUN's you mean software RAID.
Software RAID is "poor man's RAID".
I assume that you have a hardware RAID5 controller.
There is little point in using both at the same time. Software RAID uses CPU cycles which can be bad on a system loaded with apps.
Originally there was RAID3. This striped the data over a number of drives and also had a dedicated parity drive. This meant that every file write involved a write to the parity drive hence creating a bottleneck. So RAID5 was created.
RAID5 is striped data with rotating parity. The parity function is rotated between all the drives eliminating the bottleneck. I/O is spread across a number of actuators (drives) so the more drives in the RAID5 the greater the I/O bandwidth available. Compounding this functionality with software RAID is pointless. The hardware RAID5 controller will offload all I/O processing (parity calculation) from the main CPU of the box.
Dunno whether that answers you question(s) or not? Post back any further questions if not.
So RAID5 if good for general random I/O (mixed and unpredictable read/write)
In a situation where I/O's are predominantly read-only (eg, large Oracle database with mainly read enquiries) then RAID3 will be a bit faster because there's no need to read the parity if drives are healthy.
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LEARN ABOUT SUNOS
raidctl
raidctl(1M) System Administration Commands raidctl(1M)
NAME
raidctl - RAID hardware utility
SYNOPSIS
raidctl -c disk1 disk2
raidctl -d disk1
raidctl [-f] -F filename controller...
raidctl -l [controller...]
DESCRIPTION
The raidctl utility creates, deletes, or displays RAID volumes of the LSI1030 HW Raid controllers that include RAID support. The utility
also updates firmware/fcode/BIOS for both RAID and non-RAID controllers.
The raidctl utility requires privileges that are controlled by the underlying file-system permissions. Only privileged users can manipulate
the RAID system configuration. If a non-privileged user attempts to create or delete a RAID volume, the command fails with EPERM.
Without options, raidctl displays the current RAID configuration on all exisiting controllers.
OPTIONS
The following options are supported:
-c disk1 disk2 (for on board)
Create a mirror using disk1 and disk2. Replace the contents of disk2 with the contents of disk1. Specify disk1 and disk2 in canonical
form, for example, c0t0d0.
When you create a a RAID volume, the RAID volume assumes the identity of the first target in the disk pair (disk1). The second target
(disk2) disappears from the system. Therefore, the RAID volume appears as one disk.
To have a successful RAID creation, there must not already be a RAID configuration present on the specified controller. Additionally,
the secondary disk must not be mounted, as it has all its data erased and replaced with the primary disk's data.
-d disk1 (for on board)
Delete the RAID volume specified as disk1.
Specify disk1 in canonical form, for example, c0t0d0.
-f (for HBA)
Force an update. Do not prompt.
-F filename controller (for HBA)
Update the firmware running on the specified controller (controller).
-l [controller ...] (for on board)
List the system's RAID configuration. If controller is specified, list RAID configurations for controller.
Output from the -l lists the following information:
RAID Volume Displays logical RAID volume name.
RAID Status Displays RAID status as either RESYNCING (disks are syncing), DEGRADED RAID is operating with reduced functionality),
OK (operating optimally), or FAILED (non-functional).
RAID Disk Displays RAID disk name.
Disk Status Displays disk status as either OK or FAILED.
EXAMPLES
Example 1: Creating the RAID Configuration
The following command creates the RAID configuration:
# raidctl -c c0t0d0 c0t1d0
RAID Volume 'c0t0d0' created
Example 2: Displaying the RAID Configuration
The following command displays the RAID configuration:
# raidctl
RAID RAID RAID Disk
Volume Status Disk Status
----------------------------------------
c0t0d0 RESYNCING c0t0d0 OK
c0t1d0 OK
Example 3: Deleting the RAID Configuration
The following command deletes the RAID configuration:
# raidctl -d c0t0d0
RAID Volume 'c0t0d0' deleted
Example 4: Updating Flash Images on the Controller
The following command updates flash images on the controller:
# raidctl -F lsi1030.fw 0
Update flash image on controller 0? (y/N): y
Flash updated successfully
EXIT STATUS
The following exit values are returned:
0 Successful completion.
1 Invalid command line input.
2 Request operation failed.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |SUNWcsu |
+-----------------------------+-----------------------------+
SEE ALSO
attributes(5)
System Administration Guide: Basic Administration
SunOS 5.10 17 Aug 2004 raidctl(1M)