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Since installing Fusion my Mac Pro seems to hang (SPOD) more often even when Fusion isn't running. Has anybody else experienced this? My Mac Pro never used to display the SPOD at all but now it happens every day. I've got plenty of memory (12GB) and the hard drive is at less than 50% capacity.

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Does it happen even when Fusion is not running? – sirlancelot Aug 7 '09 at 16:13
On a related note, VM also provides an extreme drain on battery life on macs – Evan Aug 7 '09 at 17:46
up vote 3 down vote accepted

VMware Fusion has a few daemons running always, even if it's not open:

  • vmnet-bridge
  • vmnet-dhcpd
  • vmnet-netifup
  • vmnet-natd

as well as the application '/Library/Application Support/VMware Fusion/VMware Fusion'

I'm not convinced these would be the cause of your issues, though.

Have you tried removing VMware Fusion and seeing if the problem persists? Have you checked for other services starting at login, for example?

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The performance impact of the daemons should normally be minimal. – alex Aug 30 '09 at 7:34

As soon as you start doing heavy disk I/O in your VM (or anywhere on your system) this will affect your overall performance. Even if you have multiple CPU's or a lot of memory available.

In Fusion's preferences ("General" -> "Performance") you have the option to optimize it for "virtual machine disk performance" or "Mac OS application performance". Try switching this option and check if it helps your system performance.

I have never experienced a hang or crash caused by Fusion myself.

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VMWare Fusion often puts pressure on the hard drive I/O system. This happens particularly when, for example, you are snapshotting. But as a general rule, anything you are doing inside of VMWare that hits the disk hard will significantly affect performance of the guest.

If you are getting the SPOD even when not running Fusion, I have no explanation. VMWare Fusion certainly loads some device drivers but this should not cause SPOD to occur more frequently. Indeed, I do not experience this and I have one quarter as much RAM as you.

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If you check in terminal after a reboot and without VMware running, you will always see the VMware Fusion running. I have not found the script that launches this yet, but by killing the process, I speed up the Macbook significantly.

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Leave Activity Monitor turned on; also, after turning it on, go to View -> Dock Icon and show either CPU usage or Disk usage. When you start having performance issues, go to Activity Monitor and check what's using the most CPU cycles.

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FWIW: My Mac Pro (early 2008) with Fusion 2.0.5 is rock solid and I do not have the problems you describe. I have been using 6 GB RAM since I bought the machine and only recently upgraded to 10 GB. Primarily, I use primarily one VM at a time (most often a Linux distribution).

Regarding Fusion: Did you try changing the Preferences->General->Performance setting from what you currently have? I selected 'Optimize for Mac OS Application performance'. This means that Fusion avoids caching data in the Mac OS caches. Also, there was a bug in Mac OS X 10.5.0-10.5.4 (IIRC) which cause problems regarding this switch and could lead to hangs. So make sure you are running latest Mac OS X and Fusion version! (It's e.g. mentioned in the Fusion 2.0.2 release notes).

Do you have the latest VMware tools installed inside your VMs?

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My Mac OS X 10.6.2 has issues running VMware Fusion 3 especially running Windows 7. Got the SPOD over the last couple days. I need to research a bit more to figure out if specific apps running on Windows 7 causes the problem.

I see hangs with MS Office 2008 Word running natively in Mac OS X as well but less consistent.

Being new to Mac, only using for the last month, I'll be looking into these type issues over the next few months.

If doing a lot of Windows on the Mac, I may end up using BootCamp instead of Fusion.

I have not seen any issues yet with Ubuntu 9.10 running on Fusion.

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