7 Replies Latest reply on Jul 12, 2007 6:29 AM by nick.couchman

    VMWARE SERVER 4GIG MEMORY MAX ALLOCATION

    Build_Interns Enthusiast

      Alright guys, from my memory I think from the other thread it was stated that the MAXIMUM amount of memory VMServer can allocate to all the Virtual Machines running is 4 gigabytes.  Now, I tried this and I was able to actually run  six virtual machines each with 1 gigabyte.  Now this was going extremely slow.

       

      So my question is IS IT GOING SLOW because our host machine only had 7.8 gigs of memory?

       

      Also if I am MISTAKEN and I did something wrong and the maximum allocation IS 4 gigabytes.  IS there a way to run TWO instances of VMWare Server such that I can run host more Virtual machines at the same time?

       

      Any help is much appreciated.

        • 1. Re: VMWARE SERVER 4GIG MEMORY MAX ALLOCATION
          nick.couchman Champion

          You are mistaken - it has been stated that the maximum amount of memory that can be assigned to a single VM is 3.6GB.  VMware Server will use as much RAM as your have with this limitation - so if you have 16GB, you can use almost all of that for your VMs (you have to leave a little room for overhead).  So, if you had 16GB of RAM, you could run 4 VMs with 3.6GB allocated to each VM.

           

          I'm not sure what host O/S you're using, but once you get above a certain amount of memory in a VM you have to start doing some performance tweaking.  I've found that if I allocate anything more than 1GB of RAM to a single VM I have to use set the option:

          mainMem.useNamedFile = "FALSE"

          /code

          in the VMX file.  If I don't, I start losing a lot of performance to disk I/O.  That option has some caveats to it - things you have to be careful of, but it vastly improves performance for me every single time I use it.

           

          P.S. - PLEASE DON'T USE ALL CAPS - EVEN IN YOUR SUBJECT LINE.  IT SOUNDS LIKE YOU'RE YELLING, AND YOU DON'T NEED TO YELL TO GET OUR ATTENTION.  WE'RE GOING TO ANSWER YOUR POST, EVEN IF YOU DON'T USE CAPS.  Thanks.

          • 2. Re: VMWARE SERVER 4GIG MEMORY MAX ALLOCATION
            jnawk Hot Shot

            Wow, a little hostile there, Nick!

             

            Specifically about that overhead,

             

            For machines Memory <= 512MB, its about 10%

            For machines 512MB < Memory <= 1000MB, its about 6%

            For machines 1000MB < Memory <= 2000MB, its about 4%

            For machines 2000MB < Memory <= 3600MB, its about 3%

             

            So in your case, 4% per machine which is about 41MB, so about 246MB all up is your overhead.   So, you aren't running out of memory.    Perhaps you are over subscribing your processor(s)?   How many cores does the host have, and how many virtual CPUs do the guests have?

            • 3. Re: VMWARE SERVER 4GIG MEMORY MAX ALLOCATION
              nick.couchman Champion

              No, not hostile, I just don't like being yelled at.

               

              I certainly didn't mean that little PS to sound hostile or nasty - I apologize if it did.  I was just trying to point out that the question will get answered either way - no need to yell for attention.

               

               

              • 4. Re: VMWARE SERVER 4GIG MEMORY MAX ALLOCATION
                jnawk Hot Shot

                I know, just giving you a hard time about it

                • 5. Re: VMWARE SERVER 4GIG MEMORY MAX ALLOCATION
                  KevinG Guru

                  Alright guys, from my memory I think from the other thread it was stated that the MAXIMUM amount of memory VMServer can allocate to all the Virtual Machines running is 4 gigabytes.

                   

                  VMware Server can use all the memory to run VM's that your host OS supports ans there is a 3.6GB per VM limit.

                   

                  The 4GB for all running VM's was a Workstation 5 or earlier limit.

                   

                  WS 6 now has a 8GB per VM limit and also can use all the host RAM that the host OS supports like VMware server.

                  • 6. Re: VMWARE SERVER 4GIG MEMORY MAX ALLOCATION
                    Build_Interns Enthusiast

                    Sorry about the caps - just under a lot of pressure =).

                    • 7. Re: VMWARE SERVER 4GIG MEMORY MAX ALLOCATION
                      nick.couchman Champion

                      Well, maybe he'll be ticked off you at you, but maybe not.  In this case, you being wrong was actually a better thing, because it means that VMware Server actually can support more memory than you originally told him.