How to P2V multi-proc box to uni-proc without doing a HAL downgrade?

[BenConrad]

Hi folks,

When I convert systems that have ACPI multi-proc I usually convert them to a 1 vCPU guest. I've had some performance issues with multi-proc HALs on 1 vCPU guests and I have downgraded the HAL to the unic-proc ACPI HAL several times.

The problem with this scenario is that you can't go back to multi-proc HAL after you do this .... well I guess you could try the driver rollback feature of Dev manager...

Is there a way to have the Converter only convert to 1 vCPU? I'm wondering what would happen if I used the "/numproc=number" option in boot.ini on the pHost before I run converter, setting the number of pCPUs to 1. I would still be running the multi-proc HAL on the pHost but what would I have on the VM after conversion?

Ben

[esiebert7625]

No there is no way for Converter to only convert to one cpu, see these posts. You can edit your VM before your power it on for the first time and change it to one CPU.

http://www.vmware.com/community/thread.jspa?messageID=562984򉜨

http://www.vmware.com/community/thread.jspa?messageID=575704򌣘

What OS are you running, you should be able to go back and forth between single/multi HAL pretty easily...

If you change from a multi-processor system to a uni-processor system you need to manually change the HAL on the Windows server after the conversion. To do this go into Device Manager after the machine first boots and discovers it's new hardware and then click on Computer then right-click on the processor and select Update Driver. Then select Install from specific location and then Don't search I will choose the driver to install. Then select show All compatible hardware and select the appropriate processor. For example, if you went from a dual cpu to a single cpu then select ACPI uni-processor PC instead of ACPI multi-processor PC. You will need to reboot once you change this. To verify what HAL you are using you right-click your hal.dll in c:\windows\system32 and select the Version tab and select Internal Name and it should say halmacpi.dll for multi-processor acpi and halacpi.dll for uni-processor acpi.

[BenConrad]

Thanks,

Post 575704 says that even when you start up the VM with uni-proc you stick with the same HAL you had in the physical world (interpreted). I've had a Win2003 VM that I P2V'ed yesterday that was performing terribly. I had to move to uni-proc to get the CPU usage down. So I've picked "Advanced Configuration and Power Interface (ACPI) PC", uni-proc is not available. I guess I'll use the rollback feature if I need it however the VM is behaving much better today.

Ben

[dmehringer]

I always adjust the HAL to correct this issue. With Windows 2003 you used to need a special patch, but it is now part of SP2. If you're not running SP2 then you can call M$ and ask for KB923425 which allows you to choose Choose ACPI Uniprocessor PC . I wrote a whole document on this for our company. I will paste it in for you, but of course it won't have the screenshots.

___________________________________________________________

Changing the HAL from Multiprocessor to Single processor after P2V conversion:

1. Before making any changes to the VM, Create a Snapshot in Virtual Center.

2. Right click on the VM you want the Snapshot for and go to Snapshot

3.

4. Click Take Snapshot

5.

6. Name it and click OK

7.

8. Snapshot will create

9.

10. RDP or Console into the Server and go to Device Manager

11. For Windows Server 2003, install the following hotfix. It does not require a reboot. This hotfix allows you to downgrade to Uniprocessor. WindowsServer2003-KB923425-v2-x86-ENU.exe

12. Expand the Computer tab to see what HAL is loaded

13.

14. In this case, this server used to have 2 processors when it was in its physical form. This needs to be changed. To do so, Right click on ACPI Multiprocessor PC and choose Properties

15.

16. Click the Driver tab

17.

18. Click Update Driver

19.

20. Click Next

21.

22. Choose Display driver so I can choose and click Next

23. It will show you this screen

24.

25. Choose “Show all hardware of this device class”

26.

27. Choose ACPI Uniprocessor PC and click Next

28. You will be warned about changing this driver, but don’t worry, if it fails, we can revert from the Snapshot we took!

29.

30. Click Yes to continue

31.

32. Click Next

33.

34. Click Finish

35. Click Close

36. You will be asked to reboot the computer. Here is where we will find out if it boots cleanly!

37.

38. If the Computer reboots cleanly and everything seems to work, clean up the Snapshot you took. Verify in Device Manager that the HAL has changed. This should really improve the VM’s performance!

39. To cleanup the SnapShot, Open Snapshot Manager

40.

[BenConrad]

Thanks, it's good to have this info all in one post!

I actually had to rollback to the multi-proc driver in this particular VM because the CPU requirements were so great. It's running nicely now using the multi-cpu HAL (2 vCPUs) and the %Rdy on the ESX server for this VM is nice and low.

Ben

[glynnd1]

Added link with details on how to do this under NT:

Yes this is a HAL downgrade, but I figured some poeple still have to deal with NT and will find this thread in their searches.

Message was edited by: glynnd1

Ignore the above information. Converter handles the HAL down grade under NT.

[R0v3r]

Scratch this : I was looking in the wrong place.

[ruudde]

Well in my case the first link brought back the CPU usage on the ESX server from 2600Mhz to 50 Mhz! I guess the converter didn't work here.

Thanks!

[russjar]

Howdy, firstly great post...

Now to my dilemma, I am trying to modify the HAL from Advanced Configuration and Power Interface (ACPI) PC to ACPI Uniprocessor PC on W2k3 server SP1. I've installed the hotfix and when I go through the process I don't have the option to select the ACPI Uniprocessor HAL..?

Cheers

Found this handy little tool have tried it and works....

VCP,MCSE NT4/W2k/W2k3, MCSA W2k3

Message was edited by: russjar