The Soul of a Virtual Machine : Performance

New article: Virtual Server Performance Tips

megand — Thu, 09 Jun 2005 21:58:00 GMT

Jeff Woolsey has written this article to help you optimize the performance of your virtual machines - http://blogs.technet.com/megand/articles/406145.aspx. Thanks Jeff!

PS: I'm back from my vacation (which was grand!).

New article on estimating system capacity

megand — Thu, 07 Apr 2005 05:05:00 GMT

I just posted an article on figuring out how much system capacity a host computer will need in order to run a given set of virtual machines. You can find it in the Deployment section (http://blogs.technet.com/megand/articles/category/8299.aspx).

Happy estimating,
Megan

New tool for precompacting virtual hard disks

megand — Sat, 11 Dec 2004 01:44:00 GMT

Compacting your dynamically expanding virtual hard disks (VHDs) reduces the amount of disk space they use. Preparing a disk and compacting it is covered in the Virtual Server 2005 Administrator’s Guide, so I won’t go into it here. What’s new is this: you used to have to use a third-party tool to zero out available blank space on the VHD before compacting it. Now you can use a tool that's included with Virtual PC 2004 SP1 -- the Virtual Disk Precompactor.

If you have Virtual PC 2004, you can simply install SP1 to get this utility.* Otherwise, you’ll need to download the trial version of Virtual PC 2004, and then install SP1. (If you try to install it on your Windows Server 2003 machine, you'll get a warning that it isn't a supported OS. You can ignore the warning.)

To use Virtual Disk Precompactor, you must first capture Virtual Disk Precompactor.iso, which is installed with Virtual PC 2004 SP1. For instructions on capturing media, see "Add or remove a CD or DVD drive" in the Virtual Server 2005 Administrator's Guide. Virtual Disk Precompactor.iso is located in %ProgramFiles%\Microsoft Virtual PC\Virtual Machine Additions\.

After you capture Virtual Disk Precompactor.iso, you can run Virtual Disk Precompactor from the command line by navigating to the CD drive of the virtual machine and typing Precompact. The available parameters are:

-Help - Displays help for the precompactor.

-Silent - Runs the precompactor in unattended mode.

-SetDisks - Specifies the disks to be precompacted. If this parameter isn't specified, then all virtual hard disks for this virtual machine are compacted.

Example: Precompact -Silent -SetDisks:CDE

Note that you can only compact dynamically expanding virtual hard disks. To compact fixed-size VHDs, you can convert them to dynamically expanding VHDs, compact them, and then convert them back to fixed size.

* As announced in my posting of January 12, 2005 (http://blogs.msdn.com/megand/archive/2005/01/12/351756.aspx), this tool also will be available in Virtual Server 2005 Service Pack 1.

Increasing the speed of an OS install

megand — Sat, 04 Dec 2004 02:59:00 GMT

I've just added an article contributed by Jeff Woolsey, Virtual Server Program Manager, to the "Deployment" category (http://blogs.technet.com/megand/articles/274783.aspx) that describes how to increase the speed of an operating system installation when you're using emulated SCSI disks.

Virtual PC 2004 SP1 available for download

megand — Thu, 02 Dec 2004 17:58:00 GMT

Some of you may not know that Virtual PC 2004 Service Pack 1 (SP1) is now available. It includes some fixes as well as reliability, performance, and management improvements. It's also essential if you want to run Windows XP with Service Pack 2. To download SP1, go to http://www.microsoft.com/downloads/details.aspx?familyid=b07c9ef0-265a-4237-ae3b-25bc8937d40f.

Misbehaving virtual machines

megand — Wed, 24 Nov 2004 03:03:00 GMT

If your virtual machines consistently hang or your keyboard and mouse behaves irratically, you can try one or more of the following remedies:

First of all, if the virtual machines are hanging, make sure you've got enough available memory and CPU for the combined requirements of the currently running virtual machines as well as the host. If there aren't enough system resources available, then turn off one or more virtual machines.
If the virtual machines are running on a Dell notebook computer with SpeedStep power management, go to the Dell Web site and install the latest version of the SpeedStep utility (http://support.dell.com/). If this doesn't work, try removing SpeedStep by using Add or Remove Programs or disabling SpeedStep in your BIOS. If you don't want to remove or disable SpeedStep, you can use the "Always on" Power management profile on the notebook computer.
If you haven't updated your Virtual Machine Additions, but you've upgraded Virtual Server from a pre-release version, or if you created the virtual machine in Virtual PC, install the release version of Virtual Machine Additions. For instructions, see the Virtual Server 2005 Administrator's Guide.
If you are running an anti-virus program, add *.vhd, *.vsv and *.vud files to your exception list. Be aware that the list may be reset when you upgrade your anti-virus program.
Log on as a different user to see if the problem goes away. If it does, your Windows user profile may be corrupted, which can cause the system to lock up when you right-click an item in Windows Explorer. See this KB article information about this issue: http://support.microsoft.com/default.aspx?scid=kb;en-us;555021&Product=winxp
If you're using Virtual PC 2004 with a European keyboard, the keyboard may lock up when you type Alt+G+R to create a backslash. To fix this problem, install Virtual PC 2004 SP1, which you can download for free from: http://www.microsoft.com/downloads/details.aspx?familyid=b07c9ef0-265a-4237-ae3b-25bc8937d40f&displaylang=en.
On Virtual PC 2004, you will probably experience performance issues with virtual machines running Windows XP with Service Pack 2. This is because XP SP2 was finished after Virtual PC 2004 was released. To fix the problem, install Virtual PC 2004 Service Pack 1. You can download it from http://www.microsoft.com/downloads/details.aspx?familyid=b07c9ef0-265a-4237-ae3b-25bc8937d40f&displaylang=en.
Verify that your hardware acceleration setting is set to full (right-click your desktop, click Properties, click the Settings tab, click Advanced, click the Troubleshoot tab.)