Change HAL to uniprocessor?

[travesty]

I know this topic has been covered in great detail but my experience seemed to be different then everybody elses. I powered off the VM, decreased the amount of vCPU's from 2 to 1. Powered the VM back on and went into device manager. Within device manager it listed 1 vCPU, Intel(R) Xeon(R) CPU 5160 @ 3.00GHz. Task manager only shows 1 vCPU. So what I want to verify is that this VM is definitely only using 1 vCPU. Where else can I look to find this out?

[RParker]

What does computer show under hardware device manager? It should show uni-processor HAL instead of multi-processor HAL

[khughes · Accepted solution]

Like rparker said, go into device manager (right click Computer -> manage -> device manager)

Under computer you'll see either uni-processor hal or multi-processor hal. Seeing that you just changed it it should say multiprocessor. To change it back down to uni, i would first take a snapshot incase anything funky happens. then right click it, update driver, choose manual everything (you want to choose the driver to install / dont' check the internet), then select uni-processor and next through the rest. It will prompt a reboot, once its back up it should be a true "single processor server".

• Kyle

[TomHowarth]

Travisty, what you have done is half the story, You have verified that the Guest's Hardware is running a Single CPU, however you have not verified the Guest OS. to do this, open Device Manager (right click Computer and select Manage) select the "Device manager" leaf and in the right hand screen select the "Computer" leaf , if you see anything saying MultiProcessor you are not, right click the item and select "Update Driver Software" and navigate through the wizard, selecting "Browse my computer for driver software" or similar (in other words, a manual change). click next then select "Let me pick form a list of Device drivers ...) select the relevant driver and continue, once complete shutdown and restart your guest. Note I said Shutdown and restart not restart.

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Tom Howarth

VMware Communities User Moderator

[travesty]

Thanks to everybody. I didn't expand the Computer drop down to see what was listed there. I have changed the processor to uniprocessor. Thanks for the help.

[Kahonu]

Aloha - I am trying to do the same thing but having problems... My little friend is a XP VM that was running as a 2VCPU under VMWare Server. It was conffigured as such because at the time we didn't know better. We wanted to bring it into our ESX cluster, so I used VM Converter to do so successfully. I knocked it down to 1VCPU in ESX and booted. When I try to change the CPU to Uniprocessor in Device Manager, I don't see Uniprocessor as an option. I see -

ACPI Multiprocessor PC

Advanced Configuration and Power Interface (ACPI) PC

MPS Multiprocessor PC

Standard PC

How do I get Uniprocessor to be listed as an option?? We have an XP VM that was created in ESX and it shows Uniprocessor. So my problem appears to have something to do with the fact that the VM started out on VMWare Server.

Mahalo, Bill

[Erik_Zandboer]

Hi,

first, you must tick the box to show all devices -also the unsupported ones- in order to get the uniprocessor visible. I checkied on a single VM windows XP machine, mine DOES show the ACPI uniprocessor PC. So it should be there somewhere after you expand the search to show all devices instead of just the (what XP thinks to be the ) "supported" ones.

[Kahonu]

I did this and didn't see any additional options.

[harmandeep]

me to faced the same with WinXp Sp2,Sp3 as Guests under Windows Host for VM Workstation 6.5.2

Device Manager does,nt let to install ACPI UP hal after a ACPI MPS installation ... Microsoft says there is no compatibility issue unlike VMware ...

so here is ur path

Place this MS utility and the following scipt in a Single Directory and Execute the script for getting UP from a MPS

Ulitity name : Devcon http://support.microsoft.com/kb/311272

Script : start from Below and name it as .cmd file and execute it ( in the directory containing devcon.exe )

@echo off

@title "Upgrading to ACPI Multi-Processor HAL.."

cls

echo ====================================================

echo Upgrading to ACPI UP-Processor HAL..

echo ====================================================

echo.

echo please wait..

devcon

sethwid @ROOT\PCI_HAL\0000 := !E_ISA_UP !ACPIPIC_UP !ACPIAPIC_UP

!ACPIAPIC_MP !MPS_UP !MPS_MP !SGI_MPS_MP !SYSPRO_MP !SGI_MPS_MP > nul

devcon

sethwid @ROOT\ACPI_HAL\0000 := !E_ISA_UP !ACPIPIC_UP !ACPIAPIC_UP

!ACPIAPIC_MP !MPS_UP !MPS_MP !SGI_MPS_MP !SYSPRO_MP !SGI_MPS_MP > nul

devcon sethwid @ROOT\PCI_HAL\0000 := +ACPIAPIC_UP > nul

devcon sethwid @ROOT\ACPI_HAL\0000 := +ACPIAPIC_UP > nul

devcon update %windir%\inf\hal.inf ACPIAPIC_UP > nul

echo.

echo ====================================================

echo Script Completed: press any key to reboot..

echo ====================================================

pause > nul

devcon reboot

Hare Krishna Hare Krishna Krishna Krishna Hare Hare..Hare Ram Hare Ram Ram Ram Hare Hare..Har Har Har Hare Tuun hiin Tuun

[msemon1]

By changing this to a true uni-processor HAL from a multi-processor HAL is there a big performance gain for the VM or ESX host? When we created a Windows 2003 template from

a new virtual disk, I believe it defaults to a multi-processor HAL. VMware support has told me it is ok to use this HAL for single vCPU or multiple vCPU. Is that wrong?

Mike

[msemon1]

I am showing the same options for my XP VM's

1. ACPI Multiprocessor PC

2. Advanced Configuration and Power Interface (ACPI) PC

3. MPS Multiprocessor PC

4. Standard PC

Could option #2 be the uniprocessor HAL?

Mike

[harmandeep]

For VMware Workstation it is recommended to use a ACPI UP hal for a UP Guest ... don know for Server or ESX

Microsoft says ... that u don,t need to Change back to ACPI UP from ACPI MPS ( nor it does allows in devmgmt.msc ) http://support.microsoft.com/default.aspx?scid=kb;EN-US;811366 as they say that thier ACPI MPSis compatible with UP which it is , but that incurrs performance degrades in Virtualized Env ... as per VMware

For details about HAL options , refer here to get details for each

http://support.microsoft.com/kb/309283

Hare Krishna Hare Krishna Krishna Krishna Hare Hare..Hare Ram Hare Ram Ram Ram Hare Hare..Har Har Har Hare Tuun hiin Tuun