HP XP P9000 Configuration Guide (AV400-96525, November 2012)

Configuring disk array devices
Disks in the disk array are configured using the same procedure for configuring any new disk on
the host. This includes the following procedures:
• “Changing the device parameters” (page 72)
• “Assigning the new devices to volume groups” (page 74)
• “Creating the journaled file systems” (page 76)
• “Mounting and verifying the file systems” (page 78)
Creating scripts to configure all devices at once can save you considerable time.
Changing the device parameters
When the device files are created, the system sets the device parameters to the system default
values. You might need to change a few of those values for each new OPEN-x device: For more
information, see Table 23 (page 72) and Table 24 (page 72).
• Read/write (R/W) timeout value
• Queue depth
• Queue type
Table 23 Device parameters-read/write timeout and queue type (IBM AIX)
Required ValueDefault ValueParameter
6030Read/write timeout
SimpleNoneQueue type
Table 24 Device parameters-queue depth (IBM AIX)
Recommended ValueParameter
32
Queue depth per LU
1024
Queue depth per port (MAXTAGS)
The recommended queue depth settings might not provide the best I/O performance for your
system. You can adjust the queue depth setting to optimize the I/O performance of the disk array.
Displaying the device parameters using the AIX command line
At the command line prompt, enter lsattr -E -l hdiskx, where hdiskx is the device file
name.
Example
# lsattr –E -l hdisk2
Changing the device parameters using the AIX command line
1. To change the R/W timeout parameter, enter:
chdev –1 hdiskx –a rw_timeout='60'
2. To change the queue depth parameter, enter:
chdev –l hdiskx –a queue_depth='x'
where x is a value from the previous table.
3. To change the queue type parameter, enter:
chdev –l hdiskx –a q_type='simple'
72 IBM AIX