Tune VMware Fusion Windows 8 installs on OS X

While loading Windows within VMware using one set of specifications may initially work well, many users will find that additional resources are required over time.


Running Windows on a Mac has always posed some challenges. Even with the tremendous strides Boot Camp, Parallels, and VMware Fusion have made, Mac users and administrators must periodically monitor and review virtual machine (VM) settings to ensure the VM works properly, as Windows isn't the best-behaved guest.

Earlier in the year, I recommended Mac users running Windows 8.1 on Macs dedicate a single CPU core, 20 GB of disk space, and 4 GB RAM to the VM. I noted that I'd begun my installation dedicating a single CPU core, 20 GB of disk space, and 3 GB of RAM.

A single CPU core works fine, but 4 GB of RAM provides Windows with additional headroom necessary for Windows to really perform acceptably well. Even though I only run Office and a 50 MB proprietary professional services automation application possessing cloud-powered data, Windows performance slowed noticeably after six to eight weeks of regular use.

Following a number of Windows security and performance updates, guest OS performance slowed to a crawl. A quick disk check confirmed the issue; no free space remained. 20 GB just isn't enough. Seemingly a simple problem, I configured VMware to grow the partition to 25 GB. Six weeks or so later, the same problem arose, so I expanded the Windows VM to 32 GB. Four to five weeks later, you guessed it, the same problem arose again. The VM had grown to the partition's capacity.

Enough, I thought. I'm only running Windows, Office, and a 50 MB program. That's it. I chose to drill down and determine why so much disk space was required. The culprits were Windows update and corresponding system files. While a default CCleaner purge removed only 500 MB or so of temporary internet files and other detritus, Windows' Disk Cleanup utility managed to remove approximately 8 GB of unneeded files. With the unnecessary update, hot fix, patch, and system files removed, the VM shrunk to needing only 24 GB. With the VM left at 32 GB of allocated disk space, Windows once again possessed sufficient room for additional updates, application operation, file storage, and page file growth; I no longer needed to continue growing the VM partition.

Note that running the basic Windows Disk Cleanup utility, reached by clicking Control Panel | System and Security | Administrative Tools, only removed some 10 MB. It is necessary to click the Clean Up System Files button, found on the Disk Cleanup window, and ensure the Windows Update Cleanup checkbox is selected from within the resulting Disk Cleanup tab, to purge the Update and unneeded system files. Microsoft's cleanup program notes Windows keeps copies of all installed updates, even after newer versions are installed. The cleanup program removes or compresses those files, freeing valuable space.

Lest you think Microsoft's Disk Cleanup is simply a dumbed-down substitute for manual file trimming, think again. Most IT professionals in my experience don't recommend manually removing old update files, as all kinds of issues can arise if the wrong files are removed and Windows becomes confused. When running Windows within a VM on a Mac, it's just easier to let Windows do the work.

Do you agree? Share your experience in the discussion thread below.

Get to the core of all Apple information by automatically subscribing to TechRepublic's Apple in the Enterprise newsletter.