before I buy RAIDED miniSAS.. Thunderbolt?

Discussion in 'Mac Pro' started by malch, Aug 17, 2011.

  1. malch macrumors 6502

    Joined:
    Jan 20, 2008
    #1
    Hi there,

    With the patient help from a number of you, I've settled on a good enclosure, good Enterprise drives, a nice ATTO RAID card and the right SAS cables.

    Now, though, before I hit the 'buy' button... (apologies if this is a stupid question) might Thunderbolt be about to deliver similar or faster speeds for video editing, at a cheaper cost, etc.?
    malch
     
  2. Rustus Maximus macrumors 6502

    Rustus Maximus

    Joined:
    Jan 15, 2003
    #2
    As noted in a few of the discussions on MacRumors, Thunderbolt probably brings very little advantage to the Mac Pro in its present form. Keep in mind that Thunderbolt as it stands is only equivalent to PCIe 4x speeds. Plus there seem to be latency issues. PCIe is still going to trounce TB in the immediate future for all out speed in higher end usage.

    Someone more knowledgeable than me will chime in with more details I am sure. However, I think it is safe to say you're going to be just fine with your ATTO RAID setup for a while.
     
  3. malch thread starter macrumors 6502

    Joined:
    Jan 20, 2008
    #3
    Thanks for this. I feel good about the RAIDed miniSAS... just didn't want to miss anything obvious. Sounds like I'm good to go.
    Regards, malch
     
  4. JavaTheHut macrumors 6502

    JavaTheHut

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    Aug 15, 2010
  5. JavaTheHut macrumors 6502

    JavaTheHut

    Joined:
    Aug 15, 2010
    #5
    Mind sharing your intended config?
     
  6. malch thread starter macrumors 6502

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    Jan 20, 2008
    #6
    Stardom SOHOTANK ST8-U5 box, ATTO R680 card with two Atto SFF 8088 to SFF 8088 cables, and eight Western Digital RE4 2TB drives.
     
  7. nanofrog macrumors G4

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    May 6, 2008
    #7
    No.

    The RAID card is capable of a lot more throughput.
     
  8. malch thread starter macrumors 6502

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    Jan 20, 2008
    #8
    That does it. Will now push the 'buy' button with peace of mind!
    thanks so much,
    malch
     
  9. goMac macrumors 603

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    Apr 15, 2004
    #9
    RAID card should be much better than Thunderbolt.
     
  10. JavaTheHut macrumors 6502

    JavaTheHut

    Joined:
    Aug 15, 2010
    #10
    Sorry to "hi-jack"

    If I have a MacPro5,1 with a ATI Radeon HD 5870 video card taking up the two slots 1&2
    can I run a Areca 1880 series card in the Slot5?

    Thanks All
     
  11. wonderspark macrumors 68040

    wonderspark

    Joined:
    Feb 4, 2010
    Location:
    Oregon
    #11
    I have a 2009 Mac Pro with 5870 in slot 1, and an Areca 1880 in the x16 slot 2, since the Areca requires x8. I only have four slots, though. The 5,1 Mac Pro has five slots now?
     
  12. nanofrog macrumors G4

    Joined:
    May 6, 2008
    #12
    Your system only has 4 slots.

    Slots 1 & 2 are double wide, and wired for 16x lanes. So you can place the video card in Slot 1, and an Areca in Slot 2 without any loss in bandwidth.

    Slots 3 & 4 share the same 4x PCIe lanes via a PCIe switch (so if both slots are occupied and accessed simultaneously, there will be a performance penalty). But both cards will work.
     
  13. dime21 macrumors 6502

    Joined:
    Dec 9, 2010
    #13
    LMAO, you're deluded if you believe this. Yes, Thunderbolt is "only" PCIe 4x speed... which is 16 Gbit/s, or 2 Gigabytes per second.

    Sorry, but eight Western Digital hard drives in a RAID array are not going to get anywhere even remotely close to that number. So in practice, you will see ZERO performance difference between Thunderbolt and a PCIE RAID card in the intended usage described by the OP. Never mind the fact that many PCIe RAID cards are also "only" 4x speed.

    If you were talking $20k worth of SSD drives, then yes, a high end (8x speed) PCIe RAID card is the obvious choice. For for a measly eight platter hard drives however, there is no advantage whatsoever.
     
  14. JavaTheHut macrumors 6502

    JavaTheHut

    Joined:
    Aug 15, 2010
    #14
    Got it thx - Missed the Double wide for the 1st Slot. from the exterior looks like 5 slots :) had to open the side up to see clearly printed on the Mutha-Board x16 -- Cool

    Is this one of the reasons Apple raid performance is so poor, they use the Top slot 4 rated at x4?
     
  15. nanofrog macrumors G4

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    May 6, 2008
    #15
    Not really in this particular case. The Apple RAID Pro is just a pile of junk, whether it's in 4x or 8x lanes. :eek: :p
     
  16. JavaTheHut macrumors 6502

    JavaTheHut

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    Aug 15, 2010
    #16
    Would the WD RE4 not be a waste? they are Sata II ?
     
  17. goMac macrumors 603

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    Apr 15, 2004
    #17
    Sure you will. On Thunderbolt, you hit the two Thunderbolt controllers before the external RAID card. With the RAID card internally, you drop that step.
     
  18. diik0nn macrumors newbie

    Joined:
    Nov 23, 2011
    #18
    Hey guys,
    bumping and hijacking an old thread here, sorry!
    Does anyone have experience running an Areca controller from slot 4 (4x)?
    Of course I know it will be a performance hit, thats fine, I need a decent SAS RAID for an otherwise full Mac Pro.
    Thanks for any advice or help! ^_^
     
  19. nanofrog macrumors G4

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    May 6, 2008
    #19
    It will depend on the bandwidth consumed by the card (real throughput over the PCIe bus, as 4x lanes @ PCIe 2.0 spec maxes out at 2GB/s <500MB/s per lane * 4 lanes>), and whether or not it a card in Slot 3 will be used simultaneously or not.

    Best I can offer without specifics.
     
  20. Neodym macrumors 68000

    Neodym

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    Jul 5, 2002

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