Enable HyperThreading without APIC?

cferron · 03-29-2006, 12:42 PM

When I disable APIC option in the kernel (2.6.15.4) I lost the hyperthreading feature of my processor (cat /proc/cpuinfo show only one CPU) The issue I have is that APIC seem to be causing problem with my USB mouse (move erratically sometimes) Is there an append option I could use in my lilo so I could enable SMP at boot WITHOUT APIC?

Thanks

Claude

nadroj · 03-29-2006, 02:16 PM

whats the output of 'uname -a'

cferron · 03-29-2006, 04:06 PM

Quote:

Originally Posted by nadroj

whats the output of 'uname -a'

This is the output... SMP working with APIC... remove APIC = no more SMP working...
cat /proc/cpuinfo

Code:

processor       : 0
vendor_id       : GenuineIntel
cpu family      : 15
model           : 4
model name      : Intel(R) Pentium(R) 4 CPU 3.00GHz
stepping        : 1
cpu MHz         : 3000.816
cache size      : 1024 KB
physical id     : 0
siblings        : 2
core id         : 0
cpu cores       : 1
fdiv_bug        : no
hlt_bug         : no
f00f_bug        : no
coma_bug        : no
fpu             : yes
fpu_exception   : yes
cpuid level     : 5
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe pni monitor
bogomips        : 6007.97

processor       : 1
vendor_id       : GenuineIntel
cpu family      : 15
model           : 4
model name      : Intel(R) Pentium(R) 4 CPU 3.00GHz
stepping        : 1
cpu MHz         : 3000.816
cache size      : 1024 KB
physical id     : 0
siblings        : 2
core id         : 0
cpu cores       : 1
fdiv_bug        : no
hlt_bug         : no
f00f_bug        : no
coma_bug        : no
fpu             : yes
fpu_exception   : yes
cpuid level     : 5
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe pni monitor
bogomips        : 6000.65

Linux VSS 2.6.15.4 #9 SMP Wed Mar 29 12:27:54 EST 2006 i686 unknown unknown GNU/Linux

tredegar · 03-30-2006, 06:54 AM

I think you can use the option apic=ht, which will enable hyperthreading, but that's about all.