HP StorageWorks XP24000/XP20000 LUN Manager User Guide (T5214-96092, May 2011)

Figure 43 Ports in High Speed Mode or Initiator/External MIX mode
If High Speed mode is applied to the four ports in a port block, only two of the ports can be used
for connecting the host. When hosts issue I/Os to ports, the I/Os will be processed by processors
on channel adapters. I/Os to each port will be processed by only one processor in Standard
mode, but by two processors in High Speed mode. Therefore, ports in High Speed mode can
process I/Os faster than ports in Standard mode. By balancing the workloads on the processors,
a greater improvement can be expected with the system performance.
You cannot change standard mode to high-speed mode or vice versa while you are online to the
hosts. You will need to reboot the hosts after changing the mode.
To change the configuration of a port that is being used, you must perform a backup operation
before changing the port configuration.
Port names can differ, depending on whether ports are in Standard mode, High Speed mode, or
Initiator/External MIX mode. For detailed information about port names, see tables later in this
section.
Configuring Fibre Channel Ports 69