1 Reply Latest reply on Jan 28, 2013 7:35 AM by Rahulverma201110141

    VM very slow, is that because of RAM?

    nimel Lurker

      Hi all,

      I installed VMWare Workstation 9 Trial version on my Ubuntu 11.04 machine, with Core 2 Duo 2.1GHz and 4GB RAM.

      The problem is that my VM with Windows 7 (but other as well) are very slow and PC is always working!

      Even open a small program becames hard!


      In past I used Virtualbox but no issue like that I reported.


      Reading around the web, I thought it could be a RAM problem.

      I will explain better myself: I noticed that while VirtualBox allocate each 2 GB memory in the RAM of my PC (if before start VM I had 1GB, after it starts I had 3GB) I decided for the VM.

      Workstation instead doesn't allocate my 2GB in the RAM but in a file in the VM directory!


      I tried to copy:

      mainMem.useNamedFile = "FALSE

      in the .vmx file but file is alsways allocated and VM is very slow and useless.


      How can I fix this problem? No options I seen for setting where allocate file


      Thank you in advance

        • 1. Re: VM very slow, is that because of RAM?
          Rahulverma201110141 Enthusiast
          VMware Employees

          Hey nimel,


          Welcome to the VMware communities.


          The RAM amount which you have allocated to the virtual machine might be a lot. The VM can run slow due to many reasons with the RAM being just one.


          Other main reasons could be due to lack of CPU resrouces. I see that you have a Dual core CPU and the VM might be running low on CPU resources.


          Please let us know the given observations when the slow performance issue occurs.


          1. When the VM is powered on and running, what is the CPU usage on the physical machine?
          2. How much free RAM is available on the host when the VM is running ?

          3. Does it occur with any other virtual machine as well which is running a different guest OS?


          You can find the above info in the Ubuntu Administration > System Monitor.


          I can recommend few KB articles which would help you tweak the performance.


          Troubleshooting virtual machine performance issues: http://kb.vmware.com/kb/1008360

          Troubleshooting hosted disk I/O performance problems: http://kb.vmware.com/kb/1008885


          Please also try the following:


          1. Disable Windows Advanced Graphic features

          2. If you have allocated more than 1 CPU core to the VM then reduce it to one core. Overallocation of resources to the VM, leaves less resources for the physical machine eventually slows down the host and then VM due to that.