Systems that have Intel Itanium Dual-Core processors
can support Hyper-Threading. Hyper-Threading provides the ability
for processors to create an additional logical CPU that might allow additional efficiencies of processing. For example,
a dual-core processor with Hyper-Threading active provides four logical
CPUs, two on each core. The effect that Hyper-Threading has on performance
depends heavily on the applications running on your system. HP recommends
that you start with Hyper-Threading disabled and experiment later,
if you wish.
You can enable or disable Hyper-Threading for
a system whose processors support it. To display the Hyper-Threading
state for a system, use the EFI info cpu or cpuconfig command. (The display indicates that “CPU
threads” are turned on or off.) For example:
PROCESSOR MODULE INFORMATION
# of L3 L4 Family/
CPU Logical Cache Cache Model Processor
Module CPUs Speed Size Size (hex.) Rev State
----- ------- ------ ------ ------ --------- --- -----
0 4 1.4 GHz 6 MB None 20/00 CO Active
CPU threads are turned on.
To enable or disable Hyper-Threading, use the
EFI cpuconfig threads on or cpuconfig
threads off command. For more information, enter help cpuconfig at the EFI Shell prompt or see the appropriate
hardware documentation. The recent release of the Partition Manager
also supports Hyper-Threading.
After enabling or disabling Hyper-Threading, the
system must be reset for the change to take effect. Use the EFI Shell reset command. When Hyper-Threading is enabled, it remains
active on the next reboot of the system.