I've just bought a fast core i7 laptop with 16GB of RAM running Windows 8.1.

When I run a VMware VM on this computer, the VM is extremely slow. And if I look at the host HD activity during this time, I see it remains close to 100%.

The VM (guest) is running on a windows 7 with 8GB of RAM, 500GB disk, 2 cores.

Does anyone have a suggestion where I should look to resolve this?

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    What's the guest? What's the guest settings? I'd also add that laptop hard drives tend to be 'slow' - they optimise for reduced heat and power efficiency rather than performance. On my desktop, I've tended to keep my VMs on a 7200 rpm (as opposed to the 5400 rpm) drive thats primarily used for VMs and bulk storage. Karel seems to cover most of the things I would suggest. – Journeyman Geek Aug 8 '14 at 2:46
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    Have you enabled hardware virtualization? (Intel VT-x). You'll need to enable it in the BIOS as well as turn it on in the VM settings. – Vinayak Aug 8 '14 at 3:56

When using virtual hard drives, regardless of use with or without a virtual machine, you can improve performance by hosting the virtual hard drive file on it's own physical drive to avoid IO being lost, because the host OS is using it.

You can also improve performance by using a pre-allocated space, instead of a dynamically expanding virtual hard drive.

When using virtual drives it's important to remember that file fragmentation can occur twice. Once on the host, to the virtual hard drive file, and again on the files in the virtual hard drive; defragmenting both can improve performance if there is lots of fragmentation.

Page files, and swap partitions will heavily slow a virtual machine unless they are stored on a very fast drive. Generally it's better to give the VM as much ram as possible, and then do not use a page file/swap partition.

  • is this accepted answer? – gumuruh Apr 26 '17 at 2:40

Virtual machines offer endless possibilities, so it is good to build the virtual machine on a firm foundation.

  1. Give the virtual machine enough RAM, at least 2GB.

  2. Use an SSD instead of an HDD if you have one for storing the virtual machine image.

  3. If your guest OS gives you a choice of different desktop environments, select a lightweight desktop environment to take some of the graphics processing load off the CPU. Disable fancy desktop animations and 3D effects in the guest OS.

  4. VMware Tools is a suite of utilities that enhances the performance of the virtual machine's guest operating system for supported guest operating systems and improves management of the virtual machine.

  5. In VMware Workstation 9 or VMware Workstation 10, you can assign a maximum of 128MB of video memory to the virtual machine. In VMware Workstation 11 (which will be available in has been available since December, 2014) for graphics-intensive applications, 2GB of video memory can now be allocated for additional workload processing power. VMware Workstation 15 and later supports virtual graphics memory up to 3GB.

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    I'd add the former would help if you're swapping heavily, and the latter cause spinning rust drives on laptops are slow. Depending on your laptop, adding a second, dedicated drive for VMs, either on a second HDD slot, or replacing a DVD drive may be an option as well – Journeyman Geek Aug 8 '14 at 2:47

To echo the poster above. In my experience: Hard Drive speed is the primary performance factor of desktop based VMs. Just switching from a 5400-7200 RPM drive can have a massive impact on performance. Also --- why a 500GB HD most of my server VM's don't need that much space.

Enable shared folders in your VM config so you can pass files back and forth and store large stuff outside of your VM. That way the VM isn't trying to manage that space.

Always remember VMs run best when optimized for performance. Turn off Aero and all that extra bells and whistles.

More tuning tips can be found here: http://pubs.vmware.com/view-50/index.jsp?topic=/com.vmware.view.administration.doc/GUID-E712DAE6-88DF-4208-BEFA-09513A01A26E.html


Key thing to check that most forget is to ENABLE VIRTUALIZATION in your computer's BIOS -- most computers ship with this DISABLED.

Boot your computer to get into the BIOS (usually F1 or F2 key), look for a VIRTUALIZATION setting, and make sure it's ENABLED.

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