Changing the default device parameters for AIX

Open-Systems Host Attachment Guide

Version
9.8.7
Audience
anonymous
Part Number
MK-90RD7037-31

After the storage system is installed and connected and the device files have been created, the AIX® system sets the device parameters to the system default values. If necessary, you can change the read/write time-out, queue type, and queue depth parameters for each new device using the System Management Information Tool (SMIT) or the AIX® command line (see Changing device parameters from the AIX® command line).

Note: When you set parameters for the FX devices and SCSI disk devices, use the same settings and device parameters for all storage system devices.
Note: If you installed the ODM update, skip this section and go to Assigning new devices to volume groups and setting partition sizes.

The following table specifies the read/write time-out and queue type requirements for the devices.

Parameter Name Default Value Requirement
Read/write time-out 30 60
Queue type none simple

The following table lists the recommended queue depth values for the devices. You can adjust the queue depth as needed to optimize the I/O performance of the devices. For details, see Host queue depth.

Storage system Recommended queue depth settings
VSP 5000 series Target ports:
  • 2,048 per port
  • 32 per LDEV

Bidirectional ports:

  • 1,024 per port
  • 32 per LDEV
VSP G1x00, VSP F1500
  • 2,048 per port
  • 32 per LDEV
VSP
  • 2,048 per port
  • 32 per LDEV
VSP E series Target ports:
  • 2,048 per port
  • 32 per LDEV

Universal ports:

  • 1,024 per port
  • 32 per LDEV
VSP G130, G/F350, G/F370, G/F700, G/F900 Target ports:
  • 2,048 per port
  • 32 per LDEV

Universal ports:

  • 1,024 per port
  • 32 per LDEV
VSP G200, G400, G600, G800, VSP F400, F600, F800
  • 1,024 per port
  • 32 per LDEV
HUS VM
  • 2,048 per port
  • 32 per LDEV