Performance issues with VMWare Fusion 6.01

I’ve had relatively great success with running Apple’s OS X Maverick since I installed a developer release on a second generation MacBook Air in June while at WWDC 2013.  No issues.  None.  Never-the-less, I hesitated updating my primary Mac with developer pre-release software.

When VMWare announced during this beta that VMWare Fusion for OS X was upgraded to version 6 with specific focus on compatibility with Mavericks and Windows 8 I promptly upgraded.  Running Windows on OS X 10.8 was every bit as fast as if it was running on native hardware.  No complaints…

When Apple announced the general release of OS X Maverick’s I upgraded my primary machine a 2 monitor setup to which I was looking forward to with the additional options available.  I upgraded, again, without issue.  When I started to run Windows 8 VM inside of VMWare Fusion I noticed a performance hit…  Ugh…  I knew it was too good to be true.  I can accommodate a lot in order to help satisfy my inquisitive mind however when it comes to daily workflow I have much smaller levels of tolerance.  I knew the performance issue probably had something to do with Maverick’s so I dug a little deeper and looked at the newly  refreshed Activity Monitor in OS X.  Nothing exceptional in the CPU and Memory tabs.   CPU was at a reasonable level before and after running a virtual machine in VMWare Fusion and I have plenty of room with 16GB of memory.  Nothing seemed to be pegging either metric.  I looked at Disk and Network… again nothing out of the ordinary.  Knowing that Energy was a new tab I haven’t seen before in Activity Monitor I selected it and noticed the “App Nap” column was listed and indicated “Yes” in the row defining VMWare Fusion.   App Nap is the new feature in Mavericks that allows users, thankfully, to allow OSX to put to sleep applications consuming excessive amounts of your limited battery power.  A great feature for laptop users but I’m using a desktop and plugged into AC.  Not as big of an issue at my desk.  

A quick scan of Apple’s support site led me to how to disable this feature on an app-by-app basis…  Here’s what I did:

1.  Open a Finder window and navigate to your Applications Folder

2.  Locate VMware Fusion, right click and select “Get Info”

3.  In the “General:” section of the dialog box you will see a checkbox for “Prevent App Nap”.  Make sure this is unchecked.

I terminated and restarted VMWare Fusion and launched my Windows 8 virtual machine and so far so good.  Performance picked up and I’m back to my original daily workflow.   Hope this helps other VMWare fusion users who might have similar issues.