1 2 3 Previous Next 36 Replies Latest reply on Mar 25, 2008 12:33 PM by magic-man Go to original post
      • 15. Re: 2 XP Guests, Turn off Paging?
        Peter_vm Guru
        continuum wrote:

        Got a notebook with 4Gb RAM and dual core CPU: a guest 2k3 with 2 Gb virtual RAM and 2 CPUs performs poor - same guest with 1Gb RAM - single CPU rocks.

        That is no brainer: host has only two logical CPU's - no wonder vSMP guests perform poorly.

        But OP has 4 logical CPU's in host...

        • 16. Re: 2 XP Guests, Turn off Paging?
          BassKozz Enthusiast
          Peter_vm wrote:
          continuum wrote:

          Got a notebook with 4Gb RAM and dual core CPU: a guest 2k3 with 2 Gb virtual RAM and 2 CPUs performs poor - same guest with 1Gb RAM - single CPU rocks.

          That is no brainer: host has only two logical CPU's - no wonder vSMP guests perform poorly.

          But OP has 4 logical CPU's in host...

          Good point Peter,

           

           

          continuum,

           

           

          You've got a Dual Core CPU, and your trying to run a Host+VM w/ 2cores assigned to the VM.(hypothetically 3 cores utilized = 1host, 2 vm)

           

           

          I am using a Quad Core, and trying to run Host+2xVM w/ 2 cores assigned to each VM (hypothetically 5 cores utilized = 1host, 2 vm#1, 2 vm#2)

           

           

          So would it be better to use 1 core for VM #1 and 2 cores for VM #2 (hypothetically 4 cores utilized = 1host, 1 vm#1, 2 vm#2)?

           

           

           

           

           

           

           

           

           

           

           

          • 17. Re: 2 XP Guests, Turn off Paging?
            continuum Guru
            vExpertUser Moderators

            Oh dear - the dualcore notebook was just an example - very likely 1 cpu-VMs will be faster even on a 4 core-system. YMMV

             

             

             

             

             

            • 18. Re: 2 XP Guests, Turn off Paging?
              magic-man Expert
              continuum wrote:

              Oh dear - the dualcore notebook was just an example - very likely 1 cpu-VMs will be faster even on a 4 core-system. YMMV

               

               

               

              I must say that I agree with you on this one... We must remember the difference between physical and virtual CPUS: An OS using 2 or 4 PHYSICAL CPUs has very little overhead. A VM using 2 VIRTUAL CPUs has overhead to SIMULATE the 2 CPUs... It is still up to the host to distribute the power of the 4 CPUS to the VM... As far as speed goes, my optimum speed (2k3 host, XP and Xubuntu VMs) is at 256 meg for most XP vm's and 512 for others (depending on software installed). I also found that using a separate virtual hard disk for the swap file in the guest speeds things up.

              • 19. Re: 2 XP Guests, Turn off Paging?
                BassKozz Enthusiast
                magic-man wrote:

                I also found that using a separate virtual hard disk for the swap file in the guest speeds things up.Did the separate virtual hard disk reside on a separate local disk also? or just two separate virtual HD's on the same Local HD?

                • 20. Re: 2 XP Guests, Turn off Paging?
                  magic-man Expert
                  BassKozz wrote:
                  magic-man wrote:

                  I also found that using a separate virtual hard disk for the swap file in the guest speeds things up.Did the separate virtual hard disk reside on a separate local disk also? or just two separate virtual HD's on the same Local HD?

                  Same physical disk... I am sure you MAY get a bit more if you used a different physical drive, but mine are removable so I can't always connect to the other physical drive. It also helps keep fragmentation of the VM down. I have my swap VM drive set to non persistant.

                  • 21. Re: 2 XP Guests, Turn off Paging?
                    BassKozz Enthusiast
                    magic-man wrote:
                    BassKozz wrote:
                    magic-man wrote:

                    I also found that using a separate virtual hard disk for the swap file in the guest speeds things up.Did the separate virtual hard disk reside on a separate local disk also? or just two separate virtual HD's on the same Local HD?

                    Same physical disk... I am sure you MAY get a bit more if you used a different physical drive, but mine are removable so I can't always connect to the other physical drive. It also helps keep fragmentation of the VM down. I have my swap VM drive set to non persistant.

                     

                     

                    I am running into a problem w/ your suggestion magic-man,

                     

                     

                    I setup a separate virtual disk = 2Gb Independant/Non-Persistant/Allocate All Disk Space Now

                    I then logged on to XP formated the disk (NTFS) and then setup the Virtual Memory settings, removing the SWAP from my C: drive and moved it to my new virtual disk (E:), rebooted the VM, and all was fine and well, until I shutdown the computer...

                    Non-Persistant = Changes to this disk are dicarded when you power off or restore a snapshot

                     

                    So how did you use "Non-Persistant" for a SWAP virtual drive? Did you have to re-set it up every time you shutdown the VM?

                     

                     

                    • 22. Re: 2 XP Guests, Turn off Paging?
                      continuum Guru
                      User ModeratorsvExpert

                      No need to change this after every boot.

                      Start with swap-disk set to persistent.

                      Boot once and configure to use pagefile on second disk.

                      Check if pagefile.sys exists on D:\

                      If it exists immediatly shutdown again - just to make sure the initial state of the disk is as small as possible.

                      Now set second disk to "non-persistant"

                      bingo

                       

                       

                       

                       

                      description of vmx-parameters:

                      http://sanbarrow.com/vmx.html

                       

                      VMware-liveCD:

                      http://sanbarrow.com/moa.html

                      • 23. Re: 2 XP Guests, Turn off Paging?
                        jimbo45 Hot Shot

                         

                        Don't forget that you can also turn off the paging in the Guest OS itself

                         

                         

                        Control panel ==> system ==>advanced==>performance

                         

                         

                         

                         

                         

                        Cheers

                         

                         

                         

                         

                         

                        -J

                         

                         

                        • 24. Re: 2 XP Guests, Turn off Paging?
                          BassKozz Enthusiast
                          continuum wrote:

                          No need to change this after every boot.

                          Start with swap-disk set to persistent.

                          Boot once and configure to use pagefile on second disk.

                          Check if pagefile.sys exists on D:\

                          If it exists immediatly shutdown again - just to make sure the initial state of the disk is as small as possible.

                          Now set second disk to "non-persistant"

                          bingo

                          Worked like a charm

                          If it exists immediatly shutdown again - just to make sure the initial state of the disk is as small as possible.

                          Not really nessesary because I used the "Allocate All Disk Space Now" option which created the 2GB Shell anyways... correct?

                          Also by using the "Allocate All Disk Space Now" option, it should be slighly faster then otherwise, because it doesn't have to allocate that space as the VM is running... correct?

                           

                          Thanks for all the help

                          • 25. Re: 2 XP Guests, Turn off Paging?
                            continuum Guru
                            vExpertUser Moderators

                            Why do you want to waste space for a disk that you plan to discard after use anyway ???

                             

                            When I used this procedure I created a 6 Gb sparse disk - put a 4096 Mb pagefile on it and the VM that used it was happy about the large pagefile.

                            Due to the nonpersistant-flag the file actually newer grew larger than a few MBs - seen from the host.

                            Looks like VMs do not use pagefiles to that extend that real NTs use it  - they seem to be happy if you just promise them that the large pagefile is there.

                            Anyway - find out best practice for your usage.

                             

                            Nowadays I almost never use this second disk as I found that it is not really required. YMMV

                             

                             

                             

                             

                            description of vmx-parameters:

                            http://sanbarrow.com/vmx.html

                             

                            VMware-liveCD:

                            http://sanbarrow.com/moa.html

                            • 26. Re: 2 XP Guests, Turn off Paging?
                              BassKozz Enthusiast
                              continuum wrote:

                              Why do you want to waste space for a disk that you plan to discard after use anyway ???

                               

                              When I used this procedure I created a 6 Gb sparse disk - put a 4096 Mb pagefile on it and the VM that used it was happy about the large pagefile.

                              Due to the nonpersistant-flag the file actually newer grew larger than a few MBs - seen from the host.

                              Looks like VMs do not use pagefiles to that extend that real NTs use it  - they seem to be happy if you just promise them that the large pagefile is there.

                              Anyway - find out best practice for your usage.

                               

                               

                              Good point... I did you one better.

                              1. Start VM w/ extra Virtual HD set to Persistant.

                              2. Format HD w/ NTFS

                              3. Shutdown VM

                              4. Set HD to Non-Persistant

                              5. Start VM and changed Page file from C: to E:

                              6. Shutdown and reboot.

                              So instead of setting up the Paging while the HD is in Persistant mode, I simply do this once it's switched to Non-Persistant, which keeps the HD size to a minimal...

                              The extra HD is only 34Megs when the VM is off, and who cares how big it gets when the VM is on because once it gets shutdown it flushes memory thanks to "Non-Persistent"

                               

                              Thanks for all the help   

                               

                              Nowadays I almost never use this second disk as I found that it is not really required. YMMV

                               

                               

                              Really, why is that? So much excess RAM?

                              • 27. Re: 2 XP Guests, Turn off Paging?
                                continuum Guru
                                vExpertUser Moderators

                                I guess that both procedures produce more or less the same results. When I used that trick frequently it was the time of 2k and 2k didn't like if the pagefile.sys was not present where it was expected.

                                Since XP and 2k3 this is different - it is enough if the path is set in registry

                                HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Session Manager\Memory Management\PagingFiles

                                 

                                Really, why is that? So much excess RAM?

                                 

                                Excess RAM ? - on my machines ? - never

                                No I just stopped it after some months cause I thought it was not worth the effort - maybe I was getting lazy

                                Never made any benchmarks though ...

                                • 28. Re: 2 XP Guests, Turn off Paging?
                                  magic-man Expert

                                  into a problem w/ your suggestion magic-man,

                                   

                                  I setup a separate virtual disk = 2Gb Independant/Non-Persistant/Allocate All Disk Space Now

                                  I then logged on to XP formated the disk (NTFS) and then setup the Virtual Memory settings, removing the SWAP from my C: drive and moved it to my new virtual disk (E:), rebooted the VM, and all was fine and well, until I shutdown the computer...

                                  Non-Persistant = Changes to this disk are dicarded when you power off or restore a snapshot

                                   

                                  So how did you use "Non-Persistant" for a SWAP virtual drive? Did you have to re-set it up every time you shutdown the VM?

                                   

                                  Sorry about that... I omitted one important thing in setting it up...

                                   

                                   

                                  First, set up the extra drive in the VM as persistant growable.

                                   

                                   

                                  Boot the VM, format the new drive, Then set the swap file to that drive. Allow the VM to reboot. After the reboot is done, shut down the VM and set the new drive to non persistant at that point.

                                   

                                   

                                   

                                   

                                   

                                  • 29. Re: 2 XP Guests, Turn off Paging?
                                    magic-man Expert
                                    continuum wrote:

                                    Why do you want to waste space for a disk that you plan to discard after use anyway ???

                                     

                                    When I used this procedure I created a 6 Gb sparse disk - put a 4096 Mb pagefile on it and the VM that used it was happy about the large pagefile.

                                    Due to the nonpersistant-flag the file actually newer grew larger than a few MBs - seen from the host.

                                    Looks like VMs do not use pagefiles to that extend that real NTs use it - they seem to be happy if you just promise them that the large pagefile is there.

                                    Anyway - find out best practice for your usage.

                                     

                                    Nowadays I almost never use this second disk as I found that it is not really required. YMMV

                                    I only use the pagefile method on software (like AutoCAD) and some that really crap out without the page file.. None of my VM's are set to use mre than 256 megs of RAM so a page file sometimes has to get used. Good insurance when things get tight.