1 Reply Latest reply on Aug 13, 2010 6:54 PM by Bill Gehrke

    Disk i/o question


      As I believe our workflow will be I/O bound just as it is now, the new machine I build will have a raidcard  setup for data storage. The work we do entails editing imageI up to 3--4GB max, no rendering. I haven't yet decided which sas/sata card and whether to use 600MB 10,000 sata drives or much more expensive and faster 15000 sas drives.


      1. I see a number of you are using Areca card, why? Do they have better perfomance than equiv Adaptec or LSI cards?


      2. Some of you are using raid 3 instead of raid 5, which is supported by a limited number of cards. Raid 3 is usually poor for random reads and writes but supposedly works well for large image files. I have no experience using raid 3.


      3. I would prefer to use the 10000 sata drives due to price difference but since they are slower I am thinking about using an Intel SLC SSD drive as a temporary work space drive and then move the finished image to the raid array until burrning to dvd and shipping out to client. Altough some clients may have us do 100 + images at a time, once they have been shipped and comfirmed as good we will delete them after 30-60 days. The 64GB Intel is plenty large enough for this temporary workspace and we can refresh the drive periodically to maintain the write speed without redoing anything.


      4. I haven't yet decided whether to include the OS and CS5 in the raid array or to use a separate OS 10000 disk or maybe a raid 1 mirror 10000 array using the onbord software raid. I don't want to use a large SSD fot the OS due to price/benefit cost and also don't want a raid 0 array for the OS drive as I don't want the downtime or hassle of rebuilding when it fails. The OS disk is mostly reads and few writes so I beleive a mirror will read almost as fast as a stripe and write about as fast as a single disk but if anyone has a different experience please comment.


      5 I will probably use 8 disks for sata raid and 8 for sas along with the OS disk/disks and a SSD drive if beneficial.


      Please comment and tell me what you don't like or do like and why.



        • 1. Re: Disk i/o question
          Bill Gehrke Most Valuable Participant

          Your information has me confused. You keep talking about images (imagel?) and say no encoding, I see nothing to convince me that we are talking about normal video editing.  What is it that needs the high I/O.


          1. There is nothing better for the highest speed RAID than the Areca controllers.
          2. No comment
          3. With the high end Areca controllers you can achieve the same high speed transfer rate with more 7200 rpm drives and save a lot of money and have lots more storage
          4. You definitely do not want the OS and applications on the same drive. I would avoid using RAID of any sort on the boot drive.  You do not need a large OS/applications drive .


          Take a look the best Disk I/O results in PPBM5 Results for good disk systems