1. Identify the disk:
# ioscan -mdsf /dev/rdisk/disk69
Persistent DSF Legacy DSF(s)
2.Use the scsimgr utility to check the load balancing policy:
# scsimgr get_attr -D /dev/rdisk/disk69 -a load_bal_policy
SCSI ATTRIBUTES FOR LUN : /dev/rdisk/disk69
name = load_bal_policy
current = least_cmd_load <--------------------- Exisiting Policy
default = least_cmd_load saved =
3.To change the load balancing policy, use:
# scsimgr set_attr -D /dev/rdisk/disk69 -a load_bal_policy=round_robin
Value of attribute load_bal_policy set successfully
Valid options are:
Directs I/O requests through the hardware path with the least outstanding I/O requests.
Cycles I/O requests through the available hardware paths in round robin fashion.
Cycles I/O requests through the available hardware paths in round robin fashion, within the locality of the CPU on which the I/O was initiated. This is known as cell-aware round robin.
Cycles I/O requests through the available hardware paths in round robin fashion, subject to a user-assigned weight for each path. A hardware path is used until the number of I/O requests matches its weight , and then another path is chosen.
Directs I/O requests to the specified hardware path, if available.
Directs I/O requests to the specified target port, if available.
Directs I/O requests through the hardware path with the lowest memory access latency, based on its affinity with the CPU processing the I/O operation.
Directs I/O requests through a single hardware path. The chosen hardware path is the one that is least loaded when the device is opened. This algorithm is the only one supported for serial devices such as tape drives, changers, and SCSI controller devices, and does not apply to block devices such as disks.