2009 Mac Pro 5,1 RAID 0 question

Discussion in 'Mac Pro' started by macmesser, Oct 6, 2012.

  1. macmesser macrumors 6502a

    Joined:
    Aug 13, 2012
    Location:
    Long Island, NY USA
    #1
    Would the 5,1 Mac Pro (flashed) benefit performance-wise from either/or an OSX software RAID 0 or a hardware RAID 0 of two SATA III drives? From a RAID 0 of two SSD's? I assume the fraction of the PCI bus bandwidth that is used is the overall bandwidth and that this is limited by SATA. Is it possible to saturate the PCI bus with SATA II or III HDs on a SATA (II or III) controller? Would there be any point in a RAID 0 of SSDs? Thanks in advance for any insights.
     
  2. bax2003 macrumors 6502a

    bax2003

    Joined:
    Dec 25, 2011
    Location:
    Belgrade, Serbia
    #2
    Mac Pro Early2008 and Kingston HX 3K 90GB in RAID0 and single:

    [​IMG]

    [​IMG]

    I expect about the same results on Mac Pro 2009/2010/2012.
    Results speak for themselfs.
     
  3. derbothaus macrumors 601

    derbothaus

    Joined:
    Jul 17, 2010
    #3
    The Mac Pro is HW bound to it's internal controller @SATA2 3Gb speeds. You can SW RAID0 to 600Mb/s theoretical. You can also buy a 8x lane PCI card and use it to RAID0 SATA3 6Gb hard drives to 1200Mb's theoretical.
    You can only go as fast as the card you buy and the SSD's you RAID. HDD's can't take advantage of anything SATA3 right now. Mac Pro SATA bus is limited as well. These should help you out.
    http://www.directron.com/expressguide.html
    http://www.barefeats.com/nehal09.html
    http://forums.macrumors.com/showthread.php?t=1052746
     
  4. nanofrog macrumors G4

    Joined:
    May 6, 2008
    #4
    What do you intend to use this for?

    I ask, as for most applications, it's not likely to be worth it. For example, if you're wanting the OS and applications to load faster, just stick with a single SSD on one of the logic board's SATA connectors.

    As per using simple SATA cards, the PCIe bus will be the limiting factor (250MB/s per lane, and most of the inexpensive cards run 1x SATA connection per PCIe lane it uses or less). Thus throttling tends to occur. There are better cards that use more lanes and manage their use much better, but they're not cheap (and may not be bootable).
     
  5. macmesser thread starter macrumors 6502a

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    Aug 13, 2012
    Location:
    Long Island, NY USA
    #5
    Smokin'. Native Mac SATA and software RAID?

    ----------

    Thanks. Will check these links out.
     
  6. Loa macrumors 65816

    Loa

    Joined:
    May 5, 2003
    Location:
    Québec
    #6
    Hello,

    Trying to measure the performance of my Vertex 4 using a PCIe sata 3 card, but neither AJA or Disk Tester will allow me to test it. Why? (The volume boots and works normally otherwise.)

    Loa
     
  7. macmesser thread starter macrumors 6502a

    Joined:
    Aug 13, 2012
    Location:
    Long Island, NY USA
    #7
    Thanks for response. I didn't realize that the PCIe bus would be the limiting thing.

    For now, primarily Photoshop and other digital photography stuff, database, light video and sound track creation and editing. Doc scanning. For recreational use, flight simulator and 3D modeling. I have an SSD boot drive. Setup is probably adequate for now but I need external storage enclosure of some sort, preferably with removable drive trays, for backup. I'll need an eSATA or USB 3 card. For not too much more I might be able to get a good deal on eSATA RAID enclosure/card and I'd be done for a while. Really just trying to understand the issues so I can maximize performance on my budget. Most of what I've been looking at has been relatively low end (like the Cineraid cr-H252w/USB 3 card, reputed to be slow). With a little understanding of the issues I might be able to squeeze out a little better system with some components that have the potential to be eventually repurposed.
     
  8. nanofrog macrumors G4

    Joined:
    May 6, 2008
    #8
    Sometimes. More often, it comes down to the controller chip used on the card (not only it's SATA specification, but how it handles PCIe traffic).

    Which is why the more expensive cards tend to run faster, even if the SATA specifications are the same vs. a budget card (better PCIe traffic management, which requires more than 1x PCIe lane).

    Here's a possible configuration that should improve matters noticeably without breaking the bank...

    Primary storage:
    • SSD for boot/applications
    • SSD for Photoshop scratch (separate unit, not shared with OS/applications; does not need to be very large either, so something like a 40GB would do)
    • HDD for data
    All of this using the MP's SATA ports, no cards or USB ports at all (makes it more cost effective).

    If you're after faster ports, then it's going to get expensive (need 2x PCIe lanes per SSD or better + boot capable = ATTO or Areca RAID cards). Areca's cheaper but probably a lot more than you're expecting (i.e. ~$360 for an ARC-1213 4i, and more for an ATTO, and it can go up from there <over $1k just for a card :eek:>). Speed is not cheap, and the faster you try to go, the uglier the price tags get.

    Backup system:
    • PCIe SATA card that works with Port Multiplier based enclosures
    • Port Multiplier (PM) based enclosure (note that one SATA port is good for up to 5x disks max, so if you need 8x disks, then you'd need a 2x SATA port PCIe card).
    • HDD's (Green models will do for backup)
    • Configure as single disks, or perhaps JBOD via Disk Utility (10 would cut your storage capacity in half, while JBOD allows you access to all of it in a single volume).
    Example kits that you'd only need to add drives (4 disk version, 8 disk version).

    This is on the slow side, but it's backup, not primary storage = acceptable solution.​
     
  9. macmesser thread starter macrumors 6502a

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    Aug 13, 2012
    Location:
    Long Island, NY USA
    #9
    Thanks for reply. This info gives me something to go on. The SSD scratch disk seems like an excellent idea, especially now that good deals are available on smaller capacity SSDs. Would you recommend a multi-lane PCIe card for the eSATA enclosure? What about USB 3.0 for external drives instead?
     
  10. nanofrog macrumors G4

    Joined:
    May 6, 2008
    #10
    You can if you wish (faster eSATA product or USB 3.0), but backups don't have to be that fast (i.e. schedule full backups overnight) which can allow you to save money.

    Single disk speeds are sufficient for what you're describing as your usage (for backup), including Green models.
     
  11. macmesser thread starter macrumors 6502a

    Joined:
    Aug 13, 2012
    Location:
    Long Island, NY USA
    #11
    Thanks again. A multi drive enclosure in single disk mode and swappable trays with WD Caviar Greens should do it. Three 2 or 3 TB drives to start with.
     
  12. nanofrog macrumors G4

    Joined:
    May 6, 2008
    #12
    :cool: NP. :)
     

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