How to change Emulex HBA queue depth options in RHEL 6

Changing the queue depth of Emulex HBA

For Changing maximum queue depth settings in Emulex HBA on servers running RHEL 6 loading and unloading lpfc module is needed. The Emulex HBA support the following options to influence the queue depth settings :

# modinfo lpfc|grep queue_depth
parm: lpfc_lun_queue_depth:Max number of FCP commands we can queue to a specific LUN (uint)
parm: lpfc_hba_queue_depth:Max number of FCP commands we can queue to a lpfc HBA (uint)

Step 1.In RHEL 6 create a module related file under /etc/modprobe.d/ by name lpfc.conf ” and add:

options lpfc lpfc_hba_queue_depth=32
options lpfc lpfc_lun_queue_depth=32

Step 2. Rebuild the initial ramdisk image in RHEL 6:
2a. It is recommended you make a backup copy of the initrd in case the new version has an unexpected problem :

cp /boot/initramfs-$(uname -r).img /boot/initramfs-$(uname -r).img.bak

2b.Now rebuild the initramfs for the current kernel version:

#dracut -f

Reboot the servers and verify the lpfc_hba_queue_depth and lpfc_lun_queue_depth values.