6 Replies Latest reply on Jul 26, 2015 1:10 PM by brianc37193333

    media cache disk size and speed


      I have built my first editing PC. I have a RAID0 for my media drive with  a sequential read speed of 350MB/s. I will have the media cache on  another drive but before I buy it I was curious to know if anyone has an  opinion on whether the speed of the drive is important. If I bought a  drive with a read of 150MB/s will that keep up with the media drive  during work or dose the media cache drive need to be the same speed as  the RAID to create a balanced system.
      The second question was what do you think a good ball park ratio for  space needed is? If the media drive is 6TB should the media cache drive  be 6:1-1TB, 12:1-500GB or smaller meaning it could be economical to have  a SSD.

        • 1. Re: media cache disk size and speed
          Jim_Simon Level 9

          [Moved to Hardware forum.]

          • 2. Re: media cache disk size and speed
            Bill Gehrke Most Valuable Participant

            Just how much media do you need online at any particular time?  You can clean the media cache when you are through with any project.  If you reopen an older project it will just recreate the media cache.  I would think that just one good SSD drive should be more than adequate.  My favorite Samsung 840 Pro would be faster than your media RAID as long as you have an SATA III interface available for it.

            • 3. Re: media cache disk size and speed
              yadnom1973 Level 1

                 Thanks for replying to my question and I'm sorry about the delayed response, this site seems to hang a lot when I try to log in.

                 Yes I have a spear SATA 3, buy what you say I presume you feel the media cache must be just as fast as the media?

                 How much media do I need on line?For online content that I sometimes make for folk very little really but this new PC and the trials and tribulations of building and learning haw to run it are down to short film competitions and wanting to start shooting in raw with the new affordable cameras that are popping up. It all seems to be changing on a daily basis but at present the most likely workflow I should think is still proxy though I am looking forward to trying out the Ciniform codec. I would also like the option of trying top do something a bit longer next year maybe and have chosen this set up for it's expandability.

                 I have never really concerned myself with how large the media cache is compared to my media, I know it's only a fraction of the size but do not know what fraction, 1/5th 1/100th 1/1000th? As I'd like to invest in a scratch drive and have it large enough to accommodate my media drive for future projects it's suddenly a relevant question. If my media drive is 6TB of which 4TB is useable I would like to buy a media cache to accommodate 4TB, one 5th would mean i needed 500GB but one 100th would mean a SSD.

                 Most SSD's these days would be faster that my RAID so that's not a problem but I'm not sure I need the speed? Dose the media cache drive need to read at the same speed as the Media drive? As an extreme example if I had a raw cinemaDNG file grading in Resolve, the single stream is somewhere in the region of 150MB/s, would the accompanying render and preview files on the media cache need to read at the same speed for play back?

                 If it's size I need and not speed then a HDD would be best, If it's speed i need and not size then a SSD, but what size? they scale in price quite quickly.

                I'm quite new to all this so if any of what I saw sounds like gibberish or is completely wrong I'd appreciate being told so.

              • 4. Re: media cache disk size and speed
                cc_merchant Level 4

                With only a few small projects under way, my media and projects occupy around 500 GB and my media cache around 160 GB, but I have not cleaned up the media cache recently.

                • 5. Re: media cache disk size and speed
                  yadnom1973 Level 1

                      Yeh I have  more, it's also the damn GoPro that I have been using recently for some stuff. It gets great shots where you couldnt normaly go but eats up so much space once you convert the files.

                      I'm shocked at how big your media cache is. I was begining to think I'd gone a bit OCD but that's a fair size cleaned or not.

                      I've down loaded some raw DNG's. I'll put 1 GB through resolve and see what cash it makes for a grade, if any? Then i'll put 1 GB of 2K unconpressed GoPro on the Premier timeline and do a little edit to see the same. Be a good work out for my new PC and I can switch the cache bettween my backup HDD and my OS SSD to see if the speed makes any difference

                  • 6. Re: media cache disk size and speed

                    how fast should an external drive used for media cache be?  or what is the lowest you should go.  I have been using an external 7200rpm with usb3.0 on my home system.  but it's only transferring at 136mb/sec.  is that sufficient?  or do I need more?