How much faster is RAID0?

Discussion in 'Mac Pro' started by netdog, Jan 28, 2008.

  1. netdog macrumors 603

    netdog

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    #1
    I currently have my home directory and data on a RAID1 using two F1 750s (7200, 32MB cache on each). If I reconfigure them as a RAID0 array (software based), I know that it will be faster working in video, but will I get any real speed increases in everyday use? What kind of differences might I expect and when?

    Also, should I move my applications over to the RAID, either in 0 or 1, as the read times should be faster and hence the load times faster, yes? Is it possible to move applications to a drive other than where the system resides?
     
  2. Anonymous Freak macrumors 601

    Anonymous Freak

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    #2
    Wirelessly posted (Mozilla/5.0 (iPhone; U; CPU like Mac OS X; en) AppleWebKit/420.1 (KHTML, like Gecko) Version/3.0 Mobile/4A93 Safari/419.3)

    Check out Ars Technica's RAID article from a couple years ago, as well as the one on Storage Review. They both basically say that unless the individual drive's speed is actually preventing you from doing something (like capturing raw uncompressed 4K video,) a RAID-0 has almost zero impact on everyday performance. (Such as app loading, game level loading, etc.) RAID-1 provides redundancy in the event of hardware failure, but "RAID"-0 increases the odds of losing data. There are extraordinarily few tasks that would be disk-bound on your drives, so I'd leave well enough alone.
     
  3. trule macrumors 6502

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    #3
    When I ran a RAID 0 array with 2 disks on my windows box everything ran faster. I miss it :(
     
  4. MrPDaddyHimself macrumors regular

    MrPDaddyHimself

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    #4
    My 3.2 on order will have 4 - 1TB drives installed with a RAID card. I do alot of After Effects, some video, Photoshop and Graphic Design Work. What would be the best RAID setup for me? I'm thinking 0+1 but I would like other opinions. Would this option be a mirror of two of the TB drives thus giving me 2TB of actual space?
     
  5. m1stake macrumors 68000

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    #5
    That's correct. It's the best RAID IMO, it's safe but also performs better.
     
  6. flyingscott macrumors regular

    flyingscott

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    #6
    I'm confused why people think they need RAID? I have worked on RAID setups and seen no performance difference... I deal with HD video (1080P footage) off an external FW800 drive and it works just fine. What am I missing???
     
  7. MrPDaddyHimself macrumors regular

    MrPDaddyHimself

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    #7
    m1stake, were you referring to what I said or someone else? Thanks.
     
  8. Danksi macrumors 68000

    Danksi

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    #8
    Since yours is coming with a RAID card, you could use RAID5.

    (RAID 0/1 are available with OSX, with or without the RAID card)
     
  9. amik macrumors regular

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    Dec 11, 2007
    #9
    Correct me if I'm wrong, but Firewire 800 would be your bottleneck even with just a single HD, so Raid 0 couldn't make a difference in your case.

    If you are saying that FW800 is fast enough, you are probably right, but a lot of people aren't satisfied until they know they've got the fastest setup in town. I for one will take redundancy over speed, and I'll take extra space over both since I backup regularly.
     
  10. 4JNA macrumors 68000

    4JNA

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    #10
    i will second this. with 4 1tb drives, using raid 5 you get 3tb of usable space and data security. with raid 0 + 1, you will only end up with 2tb, and be less safe in the event of a drive failure. just my 2 cents. best of luck with that monster!
     
  11. aLoC macrumors 6502a

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    #11
    I tried it for a while and it does make a difference but only in a few cases. For example I tried playing 6 HD quicktime movies at once. With RAID0 it could do it, but without RAID0 the HD could not keep up and the movies jumped and skipped.

    That's not a very practical example but it does show that it enables more bandwidth off the disk.
     
  12. Consultant macrumors G5

    Consultant

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    Jun 27, 2007
    #12
    For some who sees no difference:

    - you do not do anything read/ write intensive (surfing the web and checking email is not harddrive intensive).
    - your computer might have some bottleneck somewhere, such as being old and does not have the CPU or bus bandwidth to handle software raid, etc.
    - you cannot perceive the difference between (an example) 4 seconds and 2.5 seconds.
     
  13. jconly macrumors member

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    #13
    So what are the speed differences between Raid 5 and Raid 0+1 / 10?

    I'm in the process of building a full archive and working system for my imaging workflow. The RAID array will be used for my WORKING images, backed up to JBOD drives on a nightly basis. My main concern with raid is speed (opening 3-4GB files in Photoshop takes TOO long. 45min a save w/ SATA2 is not acceptable when time=money). The redundancy is second priority, and just there in case of actual disk failure. (Hence the nightly backup to an offline drive).
     
  14. sirris101 macrumors member

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    Jan 9, 2008
    #14
    RAID 0 is faster in day to day use of applications, but it's primarily faster when doing things like sustained reads & writes. These are common when working with video or audio content. People may disagree with me on the day to day applications performance increase, but I'm certain of it from both using and not using RAID 0 for years on the PC.

    Here's my experience running RAID 0 on the new Mac Pro:

    http://forums.macrumors.com/showthread.php?p=4819711
     
  15. pprior macrumors 65816

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    Aug 1, 2007
    #15
    Lots people talk trash about raid.

    Raid 5 writes SUCK. I mean STINK BAD. Reads rock, but if you're writing files much you'll pay.

    You've been warned.
     
  16. jconly macrumors member

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    #16
    Right, but what I'm asking is how much faster is RAID 0+1 compared to Raid 5.

    Just how bad are the write times?
     
  17. Pressure macrumors 68040

    Pressure

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    #17
    You do realize that an uncompressed 1080p stream requires 120MB/sec to even play smoothly?

    A single RAID-0 setup running through a Firewire800 cable will simply not be sufficient in any way.
     
  18. flyingscott macrumors regular

    flyingscott

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    #19
    I know... I didn't say uncompressed. I edit 1080p24 (apple ProRes codec) off my NON RAID external FW800 drive with ease.

    I was simply wondering, other than uncomressed video, what do people REALLY need RAID for? Again, I have worked on RAID setups and I don't see it... The only thing I see useful is for redundancy on a server.
     
  19. benpatient macrumors 68000

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    Nov 4, 2003
    #20
    i had raid 0 set up on my g5 tower, and the before/after was dramatic. i deal mainly with photoshop and indesign with some illustrator time, too, and for me, after upgrading RAM, RAID 0 was the best upgrade I did through the life of my G5. I felt like I was back on an old G3 with SCSI 320 10K drives, except with modern expectations.

    i always loved how fast those machines "felt" when using them, and the only difference between those and regular G3s was the SCSI card and drive.

    going from a single 7200rpm SATA drive to two of them in RAID 0 was a similar feeling. Everything is just more responsive. Less beach-bally action, and less time waiting for files to open/load/import/process.

    At the time, my G5, which was a dual 1.8, was faster than the dual 2.3ghz ones in xbench, primarily because the hard drive performance was off the charts.
     
  20. sirris101 macrumors member

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    Jan 9, 2008
    #21
    I can't quantify it, but from what I've read, RAID 0+1 is faster than RAID 5.
     
  21. MrPDaddyHimself macrumors regular

    MrPDaddyHimself

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    #22
    So with 4 1TB drives doing video and after effects, it sounds like 0+1 is the better option for me then is that right?
     
  22. Mr.PS macrumors 6502a

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    Jan 8, 2008
    #23
    When I ran raid0 on my PC everything was MUCH faster. I first ran a single Seagate Barracuda, then dual Barracudas in raid0, then two Raptors in raid0. Raid0 in my opinion is worth every penny, it's very fast.
     
  23. jconly macrumors member

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    Jul 12, 2007
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    New York, NY
    #24
    How significant was the difference between the barracudas and the raptors?
    I'll most likely be going with two raptors in raid 0 for scratch disk.

    I'm currently trying to figure out my best option for OS disk and USR/APP disk.
    I've read of speed benefits by seperating the two onto different disks to allow each its own channel, allowing the Os full access to its virtual mem without the demand of the apps, but would this be faster then just having them each on one raid 0. (ill be backing up to another disk regardless)?

    Ehhh actually I should be starting a new thread. Sorry OP
     
  24. Mr.PS macrumors 6502a

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    #25
    The raptors were very very fast. I could install XP in under 10 minutes.
     

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