2.3 Quad. 8MB L3 cache. Does it mean anything.

Discussion in 'MacBook Pro' started by iDemiurge, Mar 25, 2011.

  1. iDemiurge macrumors 6502

    iDemiurge

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    #1
    Ok, 0.1GHz extra is probably not worth $250. But the 2.3 has 8MB of L3 cache instead of 6MB as in the 2.2. In real-world terms, what does it mean?
     
  2. Bobby Corwen macrumors 68030

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    Jul 16, 2010
    #2
    It means you're the best.

    You're talkin to a guy who has a 17" MBP 2.3 flying in straight outta Shanghai China as we speak!!!
     
  3. Consultant macrumors G5

    Consultant

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    Jun 27, 2007
    #3
    Depends on what you do, if you just browse the web,then no difference.

    If you need to do video encoding / rendering or other cpu intensive tasks it'll save some time.
     
  4. iDemiurge thread starter macrumors 6502

    iDemiurge

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    #4
    How much time? 2.2 to 2.3 is a bit less than 5% faster. What difference does the extra 2Mb L3 cache alone make?
     
  5. binary10 macrumors member

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    Dec 17, 2009
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    in a bit register, everywhere
    #5
    L3 cache is used for pure CPU operations/instructions, it's just yet another cache before having to launch out in 'slow' (ha-ha) memory.

    You've still got Level 1 and 2 caches to hand.. but Level 3 is just giving you more instruction space to feed the 2.3 processor which will feed on them.
     
  6. Hansr macrumors 6502a

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    Apr 1, 2007
    #6
    If you need to ask you don't do the kind of stuff where the difference will be noticeable outside benchmarking things. Anyone whos day to day work will show a significant change with the added cache and minimal change in processor speed will most likely not be relying on a laptop to do that kind of work. The benefits are mainly going to be for people doing non procedural parallel number crunching.
     
  7. iDemiurge thread starter macrumors 6502

    iDemiurge

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    #7
    I'm looking into a machine for video editing, so there will be some video encoding / rendering involved.

    I know I'll be able to use the computer to its maximum performance. What I don't know is if the performance gain in this case is only marginal and not really worth the extra $$$. If it means only 2-3% faster renderings it might not be worth it. But something like 8-10% improvement would be something to consider.
     
  8. alust2013 macrumors 601

    alust2013

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    #8
    It should be 3-4% faster in rendering, maybe just a tiny bit more. I couldn't see that really being worth $250
     
  9. dime21 macrumors 6502

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    Dec 9, 2010
    #9
    Erm, not quite. CPU cache consists of both instruction cache, and data cache. It is split between the two. It is not used purely for instructions as you claim.

    To the OP: CPU cache will not give you a huge boost in CPU intensive programs. Those who've claimed that are confused and don't know what they're talking about. Large CPU cache gives you a performance boost when you're doing heavy multitasking, with lots of different programs running all at once. It does not give you any appreciable boost when running just a single CPU intensive program.
     
  10. Hansr macrumors 6502a

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    Apr 1, 2007
    #10
    Rendering is a pretty linear process and assuming that it scales linearly with the overhead being maintained constant by the IO parts. Then the speed up should theoretically be (2.3-2.2)/2.2 ~= 0,045 but in reality it's going to be different depending on a multi core rendering approach and how efficient the streamlining of such a process is. Then you also have to account for the differences in how Turbo Boost works for the two processors. I think since the blocks in question are already so large that the cache is going to have minimal effect so I'd shoot for a intuitive guess of a 3-5% speed up for rendering. Everything else related to the video editing should be the same on a human measurable scale.
     
  11. wywern209 macrumors 65832

    wywern209

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    do you rly want to know?
    #11
    get the 2.2 quad and spend the 250 towards a SSD. it will result in much faster speed in day 2 day tasks as opposed to .1ghz raise in clock speed.
     
  12. binary10 macrumors member

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    #12
    Ok accepted - data can exist in the cache. It's all 1's and 0's :)
     
  13. Bobby Corwen macrumors 68030

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    Jul 16, 2010
    #13
    See this is why I love the age of message boards: healthy counter-criticism that leads to truth which benefits us all.
     
  14. amoergosum macrumors 6502

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    Oct 20, 2008
    #14
    +1
     
  15. LunaC macrumors member

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    Feb 26, 2011
    #15
    Most benchmarks are optimized to the point that the cache is less necessary. But run a benchmark while transcoding or running an active VM and I'd presume you see more of a difference.

    In the past, Ive had applications that ran drastically faster on Xeon than consumer core, the cache size being the major difference.

    -C
     
  16. blue22 macrumors 6502a

    blue22

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    Oct 15, 2010
    #16
    what they said...

    and another "+1" to that.
     
  17. Bobby Corwen macrumors 68030

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    Jul 16, 2010
    #17
    Even if it saves you a second here and a second there, these seconds add up fast. The difference between the 2.2 or the 2.3 is the difference between spending your life in front of a computer screen waiting for something to happen, or being out there, living life.
     
  18. Mollemand macrumors regular

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    Aug 1, 2007
    #18
    I got the extra 0.1 GHz for a premium, because money is not really a big issue to me. The 8MB L3 cache was a selling factor for me, as cache is part of the bottle-neck in CPUs. To me, the premium may save me an earlier upgrade - as the CPU is something you cannot upgrade in your lap-top.

    But to be honest, it is just as much about not having to wonder if my computer is slow because I cheaped out on the last spec.

    Having said that, I think you would spend your money a lot wiser buying the 2.2 GHz and a SSD, as the SSD is really where you get your moneys worth.

    When I was on a smaller budget, I always went for the biggest bang for the buck. The 2.3 is not it. It is just the biggest bang. You will have to ask yourself: Do I need the extra 5% power for massive extra cost?

    If money is the issue, I would conclude that 'no - it's not worth it'.
     
  19. dime21 macrumors 6502

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    Dec 9, 2010
    #19
    Hahaha! :D
     
  20. Mollemand macrumors regular

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    Aug 1, 2007
    #20
    Priceless!

    Enjoy your spare-time :D
     
  21. Patman macrumors newbie

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    Nov 10, 2003
    #21
    Can someone actually do that, Geekbench with a VM or while transcoding on the 2.3ghz to see if it makes a larger difference?
     
  22. alphaod macrumors Core

    alphaod

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    NYC
  23. TheFarmer macrumors 6502

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    Jan 13, 2011
    #23
    I don't know. I've never tried anything less besides last year's iCore models.
     
  24. Patman macrumors newbie

    Joined:
    Nov 10, 2003
    #24
    Is there a measurable impact on battery life between the 2.3 and 2.2? Anyone get a chance to run multiple benchmarks/encoding to see if the 2.3ghz makes a difference or will I be the first?
     
  25. TheFarmer macrumors 6502

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    Jan 13, 2011
    #25
    Be a first! Then you and I can feel hella bada$$!!!
     

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