Device Parameters-Queue Depth - HP StorageWorks XP10000 - Disk Array Configuration Manual

Parameter
Queue type
Table 5 Device parameters-queue depth
Parameter
Queue depth per LU
Queue depth per port (MAXTAGS)
The recommended queue depth settings may 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
2. To change the queue depth parameter, enter:
chdev
where x is a value from the above table.
3. To change the queue type parameter, enter:
chdev
Example
# chdev
This changes the queue depth for device hdisk3.
4. Verify that the parameters for all devices were successfully changed.
Example
# lsattr
Default Value
None
1 hdiskx a rw_timeout='60'
l hdiskx a queue_depth='x'.
l hdiskx a q_type='simple'
l hdisk3 a queue_depth='2'
E l hdisk3
Required Value
Simple
Recommended Value
32
1024
XP Disk Array Configuration Guide for IBM AIX 17