5 Replies Latest reply on Apr 21, 2010 2:01 PM by Harm Millaard

    Page file / virtual memory

    shooternz Level 6

      WIN 7

       

      Read from some of the reference links and managed to get my self confused about setting up page file / virtual memory.

       

      Can some please tell the dummy what is best practise.

       

      eg. do I set up a pagefile on all HDDs including the system drive? 

        • 1. Re: Page file / virtual memory
          the_wine_snob Level 9

          Well, this CAN be a little tricky. For me, the ideal is to set it statically and locate it on a separate, lightly used, fast HDD. By default, it will be on the system drive, and in one installation of XP-Pro, the OS wanted at least part of it there. I located the rest on my media Assets HDD, where I store commonly used Assets, and Copy them to the Project sub-folders on the Project HDD. This gave me the fastest performance. Also, with only 4GB RAM, I went over-sized at 2.5x my installed RAM total.

           

          On my laptop, also XP-Pro SP3, I had no issue placing it on my D:\. Obviously, on the 3x HDD setup of the laptop, there really is no "unused" HDD, unlike the workstation. Again, with testing, this was slightly faster than having it on my C:\.

           

          One of the good things about a statically managed Page File, is that it is written at bootup, and will be in the same area of the HDD, each time.

           

          Harm tells me to get ready to decrease the factor of my Page File, when I move to 64-bit and a ton of RAM. He tells me that I am "so '90s," but forgets that I am older than his father, so the '90s are like yesterday to me.

           

          Good luck,

           

          Hunt

           

          PS - I have no idea how Win7-64 might have changed things, and that is why I listed my OS.

          1 person found this helpful
          • 2. Re: Page file / virtual memory
            Harm Millaard Level 7

            Craig,

             

            When setting up a Windows system, a dynamically managed Pagefile is created on the boot disk. The drawbacks are mainly two things:

             

            1. Fragmentation of the pagefile, reducing performance, and

             

            2. Multiple disk access requests on the same disk, further reducing performance.

             

            In general it is best to have dedicated disks for dedicated tasks that access each disk, so OS on 1 disk, pagefile on another disk, media on another disk, previews on yet another, etc.

             

            When setting up a new installation with newly formatted disks, I consider it best to use a separate disk for pagefile that is static and it is about the first thing I do. That will mean it is the first file created on that separate disk and will be located on the fastest part of that disk. Making it static, means that there will be no fragmentation.

             

            There used be be a golden rule to set your pagefile size to around 1.5 times the physical memory, but this dated from the time when 4 GB memory was already called huge. With 12 GB memory the norm nowadays, it does not make sense to make the pagefile larger than 8 - 12 GB. This will depend on your usual workflow. If you make it a habit to have many applications open, working in the background, AE rendering, AME handling a large queue, editing in PR, while building a disc in EN and switching back and forth between AU and PR, all at the same time, you should likely increase that figure.

             

            IMO it is not beneficial to use pagefiles on multiple disks. In my case, with 12 G memory, I use a single static pagefile of 8 G on a two disk raid0 array. I have never needed more than around 4 G max of this space.

            • 3. Re: Page file / virtual memory
              Harm Millaard Level 7

              Bill,

               

              Harm tells me to get ready to decrease the factor of my Page File, when I move to 64-bit and a ton of RAM. He tells me that I am "so '90s," but forgets that I am older than his father, so the '90s are like yesterday to me.

               

              I never realized you were over 90 years young, to beat my fathers age.

              • 4. Re: Page file / virtual memory
                shooternz Level 6

                Thanx Harm.

                (Thats what I was looking for)

                 

                Clarify that you are sugesting a HDD exclusively for the PageFile? ie sole use of the disk is virtual memory?

                 

                Clarify that "static" means that Windows is not managing the file and the user sets min and max amounts (equal to each other)

                 

                Any down side to having a pagefile on more than one disk?  How does Windows decide when & where to use pagefiles?

                 

                Summarised  as I understand it:

                Set up pagefiles first on a new system before any other installations or filing

                No pagefile on the OS disk,

                12-15GB on a disk is sufficient.

                Claim back OS HDD  page file space (defrag)

                 

                Thanx

                Craig

                • 5. Re: Page file / virtual memory
                  Harm Millaard Level 7

                  Craig,

                   

                  As I told you, I have my pagefile on my D drive, which is a 2 x 1 TB raid0. Of course it would be a waste of space to not use it for anything else, so I have all the Adobe documentation on that array, all my downloads (that are not stored on the server, but specific to my system), all my monitoring software like CPU-Z, HWMonitor, Speedfan, etc. and all my Temp files on this array.

                   

                  I changed the Windows environment variables to point to the D drive instead of the default C drive. And of course I have my GodMode directory on the D drive. In addition I use the array for 'discardable' items.

                   

                  Yes, Static means min=max.

                   

                  I never tried using multiple pagefiles on different disks, but from a logical point of view, I can't think of a single reason why that would benefit performance because of the question you raised.

                   

                  Do not forget to optimise your recovery space with 'vssadmin'

                   

                  # Go to Windows command line with administrative rights
                  # Type:
                  vssadmin list shadowstorage to see the current allocation.
                  # To change it, use:
                  vssadmin resize shadowstorage /on=[drive]: /for=[drive]: /maxsize=[size]
                  # We recommend using 1% of your boot drive, so for a 500GB drive we would set the maxsize to 5GB:
                  vssadmin resize shadowstorage /on=C: /for=C: /maxsize=5GB