h.264 encoding on the new MacPro - only 60% CPU usage?!

Discussion in 'Mac Pro' started by Nik, Mar 31, 2009.

  1. Nik macrumors 6502

    Joined:
    Jun 3, 2007
    Location:
    Germany
    #1
    I just received my brand new nehalem MacPro with 8x2.26GHz and noticed that H.264 encoding does not take advantage of all the power the machine provides.
    When I use HandBrake to encode a video in h.264 the CPU usage barely hits 60% max.

    The same goes for iMovie which only uses about 15% of the CPU when I am exporting a project.

    Is there a way to optimize h.264 encoding without buying the Elgato h.264 encoder?!
     
  2. hobes270 macrumors regular

    Joined:
    Jul 29, 2008
    #2
    Mine was the same way on the 2.26, and it took a while to do. Then that machine crashed and I just told apple to give me the 2.66Q instead. It uses all the power and got it done 3:26 quicker than the 8 core did.....Im confused too....
     
  3. bozz2006 macrumors 68030

    bozz2006

    Joined:
    Aug 24, 2007
    Location:
    Minnesota
    #3
    what version of handbrake are you using. I recently upgraded from 0.9.1 (i think), which used up almost 100% of all 8 cores of my mac pro classic. after upgrading to 0.9.3, I notice that CPU usage hovers around right around 60% of total cpu.
     
  4. trancepriest macrumors 6502

    trancepriest

    Joined:
    Nov 9, 2007
    Location:
    South Florida
    #4
    Same here... getting 25-60% core saturation on all 8 cores that I've had... including the Nehalem.
     
  5. jjahshik32 macrumors 603

    Joined:
    Sep 4, 2006
    #5
    I think everyone should wait for the next software for handbrake, it'll make Nehalem 8 core models that much faster.

    Plus dont forget 10.5.7. :)
     
  6. trancepriest macrumors 6502

    trancepriest

    Joined:
    Nov 9, 2007
    Location:
    South Florida
    #6
    [​IMG]

    Only way to get 100% core saturation on 8 core macs.
     
  7. bozz2006 macrumors 68030

    bozz2006

    Joined:
    Aug 24, 2007
    Location:
    Minnesota
  8. Mackilroy macrumors 68040

    Mackilroy

    Joined:
    Jun 29, 2006
    #8
    I've noticed on my 2.66 Quad (from 2006) on some encodes the computer will use all of my cores, and on others it will only use 60-70 percent. I have the latest version of the software, too.
     
  9. trancepriest macrumors 6502

    trancepriest

    Joined:
    Nov 9, 2007
    Location:
    South Florida
    #9
    Yeah but you are from Minnesota which automatically disqualifies you from any technical competence in this conversation.
     
  10. bozz2006 macrumors 68030

    bozz2006

    Joined:
    Aug 24, 2007
    Location:
    Minnesota
    #10
    I'm not a Vikings fan.

    try rolling back to version 0.9.1 and check your results. time an encode with 0.9.1 and 0.9.3, and check on cpu usage. h.264 encoding was supposedly optimized in 0.9.3, so even though you may not max cpu usage, that doesn't indicate that it works better/faster than 0.9.3
     
  11. Sharangad macrumors member

    Joined:
    Oct 19, 2008
    #11
    Could it perhaps be that the optical drive isn't fast enough to saturate all the cores (assuming you guys are ripping from a disc)?
     
  12. trancepriest macrumors 6502

    trancepriest

    Joined:
    Nov 9, 2007
    Location:
    South Florida
    #12
    We are smart geeks... at least I am.
     
  13. MovieCutter macrumors 68040

    MovieCutter

    Joined:
    May 3, 2005
    Location:
    Washington, DC
    #13
    I agree....stupid Vikings :D
     
  14. fatespawn macrumors member

    fatespawn

    Joined:
    Feb 22, 2009
    Location:
    Chicagoish
    #14
    Usually, my quad core reports 8x100% on CPU usage when transcoding with handbrake. However, occasionally, I will see lower usage with one core at 100%... sorta like the operation in action is only optimized for single processor. I haven't really paid too much attention though...

    As for iMovie - I don't think it's optimized for multi cores. I may be wrong about the quicktime exporting, but I think you're not going to see much of an advantage with more cores. Faster clock will make more of a difference in single core action. Right?

    -f
     
  15. xraydoc macrumors demi-god

    xraydoc

    Joined:
    Oct 9, 2005
    Location:
    192.168.1.1
    #15
    16 bars on the Activity Monitor. Neato!

    Do the new processors always show two bars per core (hyperthreading) or only when hyperthreading is somehow active?
     
  16. Nik thread starter macrumors 6502

    Joined:
    Jun 3, 2007
    Location:
    Germany
    #16
    Has the issue been solved in the meantime?

    It somehow annoys me that the saturation is only about 60% when encoding h.264 on my MacPro.
     
  17. gugucom macrumors 68020

    gugucom

    Joined:
    May 21, 2009
    Location:
    Munich, Germany
    #17
    The issue is about hyperthreading in the Nehalem machines. Hyperthreading splits the cores so you get 16 on an Octad and 8 on a quad.

    Handbrake's latest version is restricted to 8 cores irrespective of hyperthreading or not. So on a Quad Nehalem it will use all 8 virtual cores using the full CPU power. On an Octad it uses 8 hyperthreaded cores with half the capacity.
     
  18. goodcow macrumors 6502a

    Joined:
    Aug 4, 2007
    #18
    I don't think this is true because I have an 8-core (so 1600% CPU usage max via Activity Monitor) and Handbrake hovers around 1200-1300% usage when I use it.
     

Share This Page