how can I modify my windows XP guest to recognize multi core

[gthaker]

Hi:

Overall a very happy user of Windows XP guest on a linux host. I have 1 problem that I hope has a surgical solution and thus I can avoid the entire reinstall of the guest.

When I installed my windows XP guest there was an issue in the underlying Linux host kernel so only 1 of my 2 AMD processor cores were recognized. Thus, my windows guest only uses one of my 2 cores. The upgrade to Linux host has long since resolved this issue, and the host runs w/ 2 cores, but not my windows guest. I use windows guest heavily and feel if I and the 2nd core it would be a big help. I was told that "by resintalling the windows kernel" it will recognize that there are now 2 cores, but I can find no instructions on how one does this and google has been of no help in finding anything on this specialized quesiton either.

thanks in adv. for any hints/pointers/answers.

Gautam

[MarkCranness]

Set IO APIC to on in VirtualBox Settings>System>Motherboard, then use HALu to change the guest XP HAL, and change it to 'ACPI Multiprocessor PC'.

My own experience (and others) is that VirtualBox does not handle SMP (Multiprocessor) VMs well: Often the host CPU goes to 100% for no reason, even when the guest is idle. Try it and see.

These HALs require IO APIC enabled and may have host CPU usage problems:
ACPI Multiprocessor PC (HALu=ACPI Multiproccesor PC)
ACPI Uniprocessor PC (HALu=ACPI Uniproccesor PC)

This HAL doesn't care about IO APIC and will not have host CPU usage problems:
Advanced Configuration and Power Interface (ACPI) PC (HALu=ACPI PC)

Only 'ACPI Multiprocessor PC' allows the Windows XP guest to use more than one CPU or core.