Mac Pro processor "hobbled"?

Discussion in 'Mac Pro' started by DeadSirius, Nov 26, 2006.

  1. DeadSirius macrumors member

    Joined:
    Sep 16, 2006
    #1
    I have MenuMeters installed, so I can always watch my processor activity in the menu bar. It seems that processor #1 is less active than the other 3. Even when the system gets busy, and activity increases on the entire set, it seems that #1 is always a couple of notches lower than the rest. I run an eDonkey server around the clock, and it has a tendency to max out a random processor individually on a rotating basis, but #1 rarely seems to get chosen for one of these spikes.

    Hardware Test never complains about it, so I don't know if it's worth fussing about. Is there something special about the first processor that the System withholds it from regular usage?
     
  2. matticus008 macrumors 68040

    matticus008

    Joined:
    Jan 16, 2005
    Location:
    Bay Area, CA
    #2
    I don't know specifically about the newest Intel architecture, but a number of Xeon servers I've managed in years past have attempted to keep load off the #1 CPU wherever possible, to allow for processes which can't span processors or can't recognize addresses beyond the first CPU.

    I was told by an engineer friend in the mid-90s who worked with SMP that the theory was like boarding an airplane: load from the back forward, except VIP processes, which get to go where they want, when they want.
     
  3. SmurfBoxMasta macrumors 65816

    SmurfBoxMasta

    Joined:
    Nov 24, 2005
    Location:
    I'm only really here at night.
    #3
    In most SMP-aware apps (OS X) & multi-CPU systems (Mac Pro), CPU #1 is normally reserved for the OS and it's inherently complex operations of controlling everything that happens, and it assigns other, lower priority and/or less complex tasks to the rest of the available cpus.

    So yea, the OS is da VIP in this instance :)
     

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