HP-UX Virtual Partitions Administrator's Guide (includes A.05.02)

Chapter 9
nPartition Operations
Setting Hyperthreading (HT ON/OFF) and cpuconfig Primer
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Setting Hyperthreading (HT ON/OFF) and cpuconfig Primer
This section describes how to set HT ON/OFF for the latest dual-core processors which offer this feature.
For complete information on hyperthreading and cpuconfig, see the document nPartition Administrator's
Guide.
NOTE vPars and HT ON/OFF
• HT ON/OFF should be set using the EFI shell’s cpuconfig command. An alternative
method is to use the vPar Monitor’s threads command. Using setboot from within a vPars
environment is not supported.
• Although hyperthreading is supported within vPars, CPU assignments to virtual partitions
remain on a per core basis and not on a logical CPU (LCPU) basis.
• HT ON is not supported in a mixed HP-UX 11i v2/v3 vPars environment.
vPars Monitor
• to show the current HT state of the CPUs
threads without any options will show the current state of HT ON/OFF (in other words, whether
hyperthreads are turned on or off):
MON> threads
HyperThreading is currently OFF
HyperThreading will be OFF after the next nPar reboot
• to turn HT ON after the next nPar reboot:
MON> threads on
HyperThreading is now set to be ON after the next reboot
MON> threads
HyperThreading is currently OFF
HyperThreading will be ON after the next nPar reboot
• to turn HT OFF after the next nPar reboot:
MON> threads off
HyperThreading is now set to be OFF after the next reboot.
cpuconfig
• to show the current state of the CPUs, including HT ON/OFF
cpuconfig without any options will show the current state of HT ON/OFF (in other words, whether
hyperthreads are turned on or off):
Shell> cpuconfig
PROCESSOR MODULE INFORMATION
Cab/
Cell