VMware Fusion for Mac allows users to virtualize multiple operating systems on Mac OS X. For IT administrators,
this capability is essential for testing and troubleshooting code with specific operating systems and Web browsers.
In my previous article on VMware Fusion performance, I went through a few tips to get you started. Here are a few advanced tips and performance tweaks to help you get the most out of your virtual machines (VMs). I use these methods all the time on all my Macs.
Disabling graphical interfaces in VMware Fusion for Mac
After I virtualize a Windows 7 guest (or a Windows Server 2008 R2 guest, if you have the Desktop Experience feature enabled), I disable the eye candy. The Aero interface in these operating systems is cool and functional, but running those graphics-intensive operations in a VM consumes much-needed RAM and virtual CPU power.
(If you use a Windows VM for things like Internet Explorer and maybe Microsoft Office, you can enable those interfaces. But you'll notice an overall performance increase if you disable them.)
To disable Aero in Windows 7, go to Control Panel and click on System. Then select Advanced System Settings in the left pane. Under Performance, click on Settings. On the Visual Effects tab, make sure that "Adjust for best performance" is selected.
For a Linux guest, I recommend tweaking your X-Windows configuration, because it is highly customizable, both in terms of performance settings and the various window managers that can be used. Overall, X-Windows consumes fewer resources than the Windows Aero interface, and it can be used with more robust features. Consult the guides for your flavor of Linux for more information on tweaking X-Windows.
Choosing the right OS
As for virtual machine OSes, I always try to use the 64-bit version of Windows XP or Windows 7. I have a DOS 6.22 VM for troubleshooting machine-level issues, because in my line of work, you never know when you'll need it. (Yes, there are still some very old applications and hardware out there.)
Sometimes 64-bit operating systems aren't useful, though. It depends on your use, but some older 32-bit (and even 16-bit) applications may not function correctly without a 32-bit OS. The 64-bit Windows OS, whether hosted as a VM or running off physical hardware, allows for more extensive use of the virtualization technology built into the Intel processor. Therefore, it makes your VM a bit faster.
To increase performance through the VM settings, I use SCSI virtual hard disks instead of Integrated Drive Electronics. With SCSI virtual hard disks, I see a small increase in I/O for the more intensive applications, because the SCSI virtual driver is more tuned for these operations. If you use SCSI, note that XP by default will not see any hard disk available to install to. Use VMware Easy Install so the proper driver is injected into the installation.
Defragmenting disks in VMware Fusion for Mac
As with physical disks, you should defragment your virtual machine drives. I usually try to defragment my disks at least once a month, if not sooner. It's a two-step process, and if you perform only one step, you won't realize the full performance increase.
Defragment your drive as if it's a physical machine instead of a guest OS. Then open the properties of the VM, select Hard Disks and choose Clean Up Disk. This process defragments the VM file (or "package," in Mac terms) on the local or attached-storage disk.
Note that if your VM files are located on a shared network volume that uses the Host Guest File System, this step isn't necessary.
Remote management in VMware Fusion for Mac
IT administrators or application developers may need to remotely connect to a Fusion virtual machine's console screens. For simplicity's sake, you can use Windows' Remote Desktop functionality for a terminal services session connection to the VM.
But for a live remote console for Windows and non-Windows OSes that you host, the Fusion folks integrated the popular virtual network computing (VNC) client into the VM settings.
To enable this functionality, go into the settings and select Advanced. Then choose Other and click on Remote Display over VNC. Enter the username and password, and make sure you have a compatible VNC client on the machine you will connect from.
Creating backup snapshots
The AutoProtect feature basically creates snapshot backups of your virtual machines at timed intervals, similar to Windows Shadow Copies. This is a great way to ensure that your information is saved -- especially if your VM experiences a disk package corruption or an OS malfunction. Keep in mind that this feature consumes disk space, so limit the snapshots that are saved.
About the author:
Mike Nelson has been in IT for more than 20 years, with exposure to a very diverse field of technologies and solutions. He has devoted over half a decade to virtualization and server-based computing. Nelson is currently a senior analyst at a Fortune 100 company in the U.S. Midwest.