The default IBM® read/write timeout and queue depth values are different from the recommended and required values for Hitachi disk devices:
- The required value for read/write timeout is 60.
- The default value for the drive queue depth is determined by the adapter family. You can adjust the queue depth as needed to optimize the I/O performance of the devices. For details, see Host queue depth.
Note: If the AIX® host defines a device as Other FC SCSI Disk
Drive, the queue depth setting for that device is ignored, which can have
a negative impact on performance.