HP StorageWorks Disk Array XP operating system configuration guide: SGI IRIX (A5951-96075, December 2005)

Enabling comma

nd tag queuing

SCSI command t

ag qu euing must be enabled to o ptim ize the performance of the disk

array devices

. Because command tag queuing is disabled by default in IRIX, you must

enableitand

set the queue depth for each disk a rray lo g ical device (including Data

Exchange de

vices) using the fx utility.

Parameter

Required Value

Queue depth per LU

≤ 8

Queue dept

hperport

≤ 256

You can adjust the queue depth for the disk array devices later as needed (within the

speciﬁed

range) to optimize the I/O performance of the disk array devices.

To enable command tag queuing and set the queue depth for the disk arra y

devices:

1. Start the fx disk utility and select the desired device to conﬁgure.

2. When the device is selected and the fx> prompt reappears, enter /label/set/para

to set the command tag queuing a n d queue depth options.

3. When prompted, enter enable to enable comm and tag queuing, and enter the

desired command tag queuing depth (for example, 8).

4. When prompted, enter yes to modif y the drive parameters as speciﬁed.

5. Exit the fx utility, and enter yes to write out (save) the changes to the driv e

parameters.

6. Repeat steps 1 through 5 for each disk array disk device, including OPEN-x, CVS,

LUSE, and Data Exchange devices.

Installation