6 Replies Latest reply on Sep 22, 2009 9:11 AM by Mylenium

    AE CS4 isn't respecting disk cache?

    Ben Schuiling Level 1

      Hi Guys,

      I ran across a weird issue today when I was downscaling HDV footage to SD - one of my disk cache folders just kept growing.  I've enabled disk cache and set the maximum limit to be 10240 MB.  For 4/5 folders this was respected my settings but the other one ate 700 GB of my disk and in order to get my render to finish I deleted the first 256 GB of temporary files so there was room for the render to complete.

      This is the first time I've seen this problem, but it's also the first time I've done downscaling on this type of footage too.

      Has anyone else seen this issue at all?

      Thanks!

      Ben

       

      AE CS4 9.0.2

      Core i7 920

      12 GB DDR3 RAM

        • 1. Re: AE CS4 isn't respecting disk cache?
          Mylenium Most Valuable Participant

          Let's straighten out terminology first. What you are referring to is not the Disk Cache, but rather the Media Cache used to index and conform compressed media. One is persistent, the other is not. The disk cache is only used for storing RAM previewed frames overflow and is purged every time you quit AE. The media cache on teh otehr hand, is never purged unless you do so manually. That can be done from AE, Premiere Pro, Encore and Adobe Media Encoder, which share this folder because it is part of MediaCore and DynamicLink. Because they share it, it makes sense it is persistent - you wouldn't wanna have to re-conform e.g. MPEG-2 or AVCHD files every time you open a project in one of those programs. Ergo, the cache as such can grow infinitely large. Whether this is desirable is another question, but the current behavior is "as designed", so you need to manually purge from time to time.

           

          Mylenium

          • 2. Re: AE CS4 isn't respecting disk cache?
            Ben Schuiling Level 1

            Hi Mylenium,

             

            Thanks for your quick response but I'm fairly confident that I really am talking about the disk cache.  I'll tell you what I'm looking at in my settings and then you can straighten me out

             

            In my Media and Disk cache preferences I have options for Disk Cache and for Conformed Media Cache.

             

            My Disk Cache is located at D:\Temp.  I have checked enabled disk cache and set a maximum size of 10240 MB

            My Database for the Media Cache is located in C:\Users\Ben\AppData\Roaming\Adobe\Common

            My Cache for the Media Cache is located at D:\Adobe\Media Cache

             

            When I start After Effects five folders are created in my Disk Cache folder (D:\Temp) which I've set a maximum size for) under a subfolder which is named after my computer name.  The folders are named based on the process ID of After Effects instance.  One of those five folders grew larger than the limit I set for it, which seems weird to me since all the other ones worked properly.

             

            I didn't have any issues with the directories for my Media Cache cache/database folder locations

             

            Thanks!

             

            Ben

            • 3. Re: AE CS4 isn't respecting disk cache?
              Mylenium Most Valuable Participant

              I see.  The thing is, the cache you are seeing may be from some sort of pre-comp that by itself references other pre-comps. AE's cache is layer-based, so under some circumstances, it will create a file for each of the layered (nested comps), if it thinks it cannot render them fast enough when needed. In essence it is correctly respecting the limit for the parent comp, but needs to take along everything used in it, so the actual folder gets several times bigger. Another scenario where I have experienced such behavior, is if you mix sources with different color profiles, especially in 32bpc mode. In these cases AE seems to try to retain the converted frames for calculating effects faster. This only happens on systems with low memory (2GB or less), though, for apparent reasons.

               

              Mylenium

              1 person found this helpful
              • 4. Re: AE CS4 isn't respecting disk cache?
                Ben Schuiling Level 1

                Ok, that makes sense. I did have precomps referencing other precomps (scaling, color correction, etc).  One of my precomps didn't have any effects applied to it. I tried something and then just removed the effect and didn't undo the precomp.  I'm assuming that would just exasperate my situation?  Would it make a difference if I had applied an effect in that precomp at all?

                 

                So what are my best options? Should I turn off disk caching or should I just reduce it's maximum size?

                 

                Cheers!

                 

                Ben

                • 5. Re: AE CS4 isn't respecting disk cache?
                  Mylenium Most Valuable Participant

                  Well, when you turn it off, it definitely goes away. When it's on, it may be possible to minimize the disk usage, but to my recollection, you can't go below 768 MB, anyway, so this point may be moot. Effects or not should not influence the situation. The real problem at the heart is, theat even without effects, layers in pre-comps need to be "blended" to mix in transparent areas, get motion blur and so on. An effect would change the result, but not eliminate the source, so it's a lose/lose situation - if the cache is on, a frame may be stored, if the comp is complex to render, but in some situations even with effects applied no frame may be stored, because it still can be calculated in near realtime. It's really a bit complex to wrap your head around, as the whole concept is quite deep. Ultimately, you only know when you try...

                   

                  Mylenium

                  • 6. Re: AE CS4 isn't respecting disk cache?
                    Ben Schuiling Level 1

                    Sounds good!  Thanks for the direction!