Local APIC(?)+PIII mobile

Local APIC(?)+PIII mobile

[João Seabra]

Hi all

 I have an Asus S8600. 
 Mobile PIII 800Mhz + 192M RAM.
 If i select "Local APIC support on uniprocessors" the kernel while booting 
says there's no APIC present.Why?
 I know the same problem with some other laptops.
 Others detect it.
 

 At home my Athlon Tunderbird + Asus A7V133-C with local APIC enabled detects 
it but doesn seem to use it ... 

 cat /proc/interrupts
           CPU0
  0:     375529          XT-PIC  timer
  1:       7452          XT-PIC  keyboard
  2:          0          XT-PIC  cascade
  5:     113246          XT-PIC  bttv, eth0
  8:          2          XT-PIC  rtc
 10:     144373          XT-PIC  EMU10K1
 11:     382444          XT-PIC  nvidia
 12:     153864          XT-PIC  PS/2 Mouse
 14:      12346          XT-PIC  ide0
 15:         12          XT-PIC  ide1
NMI:          0
ERR:          0

Anyway why do I need local APIC :) ?What are the advantages?Links?

Thank you very much for your kindness

 Best Regards,

 João Seabra

Re: Local APIC(?)+PIII mobile

[Joel Jaeggli]

the intel 440mx chipset that the asus is based on doesn't include an apic. 
an apic is for doing multiprocessor interupt managemnet. across multiple 
I/O subsystem each can have it own set of interupts...

On Fri, 13 Dec 2002, João Seabra wrote:

> Hi all
> 
>  I have an Asus S8600. 
>  Mobile PIII 800Mhz + 192M RAM.
>  If i select "Local APIC support on uniprocessors" the kernel while booting 
> says there's no APIC present.Why?
>  I know the same problem with some other laptops.
>  Others detect it.
>  
> 
>  At home my Athlon Tunderbird + Asus A7V133-C with local APIC enabled detects 
> it but doesn seem to use it ... 
> 
>  cat /proc/interrupts
>            CPU0
>   0:     375529          XT-PIC  timer
>   1:       7452          XT-PIC  keyboard
>   2:          0          XT-PIC  cascade
>   5:     113246          XT-PIC  bttv, eth0
>   8:          2          XT-PIC  rtc
>  10:     144373          XT-PIC  EMU10K1
>  11:     382444          XT-PIC  nvidia
>  12:     153864          XT-PIC  PS/2 Mouse
>  14:      12346          XT-PIC  ide0
>  15:         12          XT-PIC  ide1
> NMI:          0
> ERR:          0
> 
> Anyway why do I need local APIC :) ?What are the advantages?Links?
> 
> Thank you very much for your kindness
> 
>  Best Regards,
> 
>  João Seabra
> -
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Joel Jaeggli	      Academic User Services   joelja@darkwing.uoregon.edu    
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Re: Local APIC(?)+PIII mobile

[Alan Cox]

On Fri, 2002-12-13 at 11:56, João Seabra wrote:
>  I have an Asus S8600. 
>  Mobile PIII 800Mhz + 192M RAM.
>  If i select "Local APIC support on uniprocessors" the kernel while booting 
> says there's no APIC present.Why?
>  I know the same problem with some other laptops.
>  Others detect it.

Because there isn't one present 8)

The APIC although on processor isnt present in all processors - at least
not all older ones. Its not a required CPU feature so not every
processor vendor includes it on all their processors.

Alan