11 Replies Latest reply on Aug 5, 2008 11:05 AM by TheRealJBergado

    Size of the swap file

    kaychan Hot Shot



      Does anyone know:

      1) How much memory we should allocated to the Service Console? Should we use the old definition of 192 mb for 8 vms; 272 for 16 vms; 384 for 24 vms and 512 for >32 vms?? I saw recommendation for 800 MB to SC on an ESX server with 32 GB of memory.

      2) How much we should allocate to the swap file?? Some recommends to double size of the memory allocated to Service Console. So if the SC is allocated 800 MB, it was recommended to make the swap file 1638 MB.

        • 1. Re: Size of the swap file
          joepje Expert

          Just use the default for COS (272 MB). In case of using agents or stuff calculate extra memory > you should test this how much overhead is created.


          Swap file I use 1024 MB. (So max I will use 512 MB for my COS)

          • 2. Re: Size of the swap file
            kharbin Master

            It depends on how responsive you need to console to be. With its default of 272MB it is memory starved and horribly slow.  So we always use 512MB minimum. Otherwise you are almost immediately using the swap.


            As for swap file size, I always use 2x the maximum RAM that can be assigned to the console, so 800MB x 2 or 1.6GB swap. that way if you bump up the RAM the swap is the correct size. Of if you scale SC RAM back, you have plenty of swap and you will need it.


            my 2 cents

            • 3. Re: Size of the swap file
              joepje Expert

              Will performance in Virtual Center 2.0 be better if you use e.g. 512 MB ?

              • 4. Re: Size of the swap file
                boydd Champion

                From what I understand - 2048MB is the maximum that will be used anyways.  I make the swap partition accordingly.  I allocate 800MB to the COS - backup agents etc.....



                • 5. Re: Size of the swap file
                  kaychan Hot Shot

                  Thanks for the response. I would certainly like to make the memory of the SC and the swap file large enough (800/1600) so that it would not starved for memory.

                  • 6. Re: Size of the swap file
                    schnj65 Novice

                    I also use 800 MB for the Service Console for Backup Agents, Dell Open Manage Agents, 16 - 20 VM's, HA agent, Virtual Center Agent

                    • 7. Re: Size of the swap file
                      nocha Lurker

                      I used the default 512MB memory size during installation of my VMware Server 1.0.3. Now when I want to increase the memory/swap file size to 1GB, I get an error message that says I have no permission to do so.

                      Can someone please teach this newbie how to increase my swap file?


                      • 8. Re: Size of the swap file
                        Texiwill Guru
                        vExpertUser Moderators



                        The SC swapfile is a partition on the disk. If you have free space after installation, which most people do not, you could create another swap partition and have 2 swap partitions. If you however do not have the space on the drive to make a new partition. You can also use a file for a swap location similar to pagefile.sys if you are a Windows person. However, this is strongly discouraged . If you do have to swap you will end up hammering the filesystem upon which it resides.


                        Now a bit of trivia. Swap partitions can be any size, however anything over 2GB per swap partition are ignored. YOu can have up to 32 swap partitions/files.


                        You would use the following


                        Create a swap partition:

                              fdisk /dev/sd?


                        Make the swap file:

                              mkswap /dev/sd?


                        Edit /etc/fstab

                              Copy the swap definition in there already and change the /dev/sd? to be the appropriate device



                             swapon -a


                        That is how you add a secondary swap partition.


                        To add a file...


                        First create a 65MB swap file:

                              dd if=/dev/zero of=/pathToSwap/swapFileName  bs=1024 count=65536


                        pathToSwap could be anything but I would put it in /var or even /tmp, depends on where you have separate filesystems. Do NOT use NFS (it does not work) and I would avoid any VMFS as well. Unless absolutely necessary avoid remote storage altogether.


                        swapFileName can be anything as well.


                        This one however requires you to edit /etc/rc.d/rc.local to add

                              swapon /pathToSwap/swapFileName


                        However, even with this discussion on adding more swap. The recommendation is if you do not have the disk space to reinstall with the proper sized swap partition which is generally 2x memory. However, remember that you may need more than one swap partition for > 1GB of memory.


                        For more information from the SC issue:

                        man mkswap

                        man swapon


                        Best regards,


                        • 9. Re: Size of the swap file
                          nocha Lurker

                          Texiwill, WOW! I'm overwhelmed by your response...my deepest appreciation for your help. I'll try that and let you know the result.


                          While I'm attempting to try your solution, I wonder whether there is any way that I can get my permission changed to allow me to edit the VM settings to increase the swap file? I installed the VMware Server so I assume I have fuill administrative permission, bit it does not allow me to change the VM settings.


                          Thanks again, Texiwill!

                          • 10. Re: Size of the swap file
                            Texiwill Guru
                            User ModeratorsvExpert



                            Are you talking about ESX or VMware Server?


                            VMs use there own swap file. The information I gave is for the Service Console only and you can not change the swap file using the VI Client directly it all has to happen from the Service Console. You however can set the Service Console Memory within the VI Client and that would require a reboot of the host.


                            Best regards,



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                            • 11. Re: Size of the swap file

                              this is the best answer.