2009 mac pro lion raid 0 slowing down

Discussion in 'Mac Pro' started by sunnyj, Feb 20, 2012.

  1. sunnyj macrumors 6502

    Joined:
    Oct 18, 2010
    Location:
    Vancouver, British Columbia
    #1
    i have two 2tb WD caviar black drives raided together. on a newly created raid the aja speed test gives me about 250 read and write speed. now its been about a month since i created the raid and the speed has degraded to about 140 read and write. even when the raid is empty the speed is 140. what could be causing the decrease in speed? i tried to verify and repair disc permissions with no speed gain.
     
  2. sunnyj thread starter macrumors 6502

    Joined:
    Oct 18, 2010
    Location:
    Vancouver, British Columbia
  3. Loa macrumors 65816

    Loa

    Joined:
    May 5, 2003
    Location:
    Québec
    #3
    Hello,

    I'm getting 270 r/w on the exact same set-up with same drives, and the RAID has been up for quite a few months now... Not sure what's wrong with yours.

    If you can empty the RAID0, why not try to rebuild it?

    Loa
     
  4. sunnyj thread starter macrumors 6502

    Joined:
    Oct 18, 2010
    Location:
    Vancouver, British Columbia
    #4
    i have 2 sets of this raid 0 setup and on both sets the performance is reduced.

    the raid set that i emptied i rebuilt it and the r/w is about 260. its a big inconvenience if i have to recreate the raids every month or so.

    what block size are you using & are you editing videos?
     
  5. Loa macrumors 65816

    Loa

    Joined:
    May 5, 2003
    Location:
    Québec
    #5
    Hello,

    32K and no. I do move large files, but nowhere near as frequently as someone editing video.

    Loa
     
  6. throAU macrumors 601

    throAU

    Joined:
    Feb 13, 2012
    Location:
    Perth, Western Australia
    #6
    Does a re-format fix it? I'm just thinking that maybe it is fragmented?
     
  7. Loa macrumors 65816

    Loa

    Joined:
    May 5, 2003
    Location:
    Québec
    #7
    Nah: simply emptying the RAID would solve the fragmentation problem, if any.

    Loa
     
  8. sunnyj thread starter macrumors 6502

    Joined:
    Oct 18, 2010
    Location:
    Vancouver, British Columbia
    #8
    i move huge files and the drives are always R/W'ing when I'm encoding videos.

    like loa said, it can't be fragmented because if the raid is empty the speed should return to normal.



    empty 1 month old raid
    [​IMG]
    newly created raid
    [​IMG]
     

Share This Page