Why does Apple include transparency when it effects performance quite a bit?

Discussion in 'OS X Yosemite (10.10)' started by bcam117, Oct 5, 2014.

  1. bcam117 macrumors member

    May 1, 2012
    I own a rMBP 2013. On the Yosemite GM candidate turning off transparency (found in the accessibility section of settings) increases 2D UI performance by quite a lot in certain areas. I'm hoping this will not be the case with the final version but looking at what happened with iOS I wouldn't put my hopes up.

    The same can be seen in iOS 7 and above. Disabling it makes certain things smoother. Even on my iPad Air, which isn't really old. This post on reddit was at the top of /r/apple. Inside you'll find people with different devices stating that this increases UI performance.

    We've been moved into world where driving 3 million pixels and above is considered normal. Apple had a huge part in this and I am thankful (although GPUs everywhere aren't :p), but why include something that puts an even greater stress on already somewhat stressed products.

    Also if anyone knows why transparency makes things a bit slow that would be great. Did it do the same on windows Visa or whatever version it was? Is it just inherent to using this effect or is it that way that it's implemented by Apple?
  2. 556fmjoe macrumors 65816


    Apr 19, 2014
    Transparency takes extra resources regardless of the OS. I'm sure they do it because people would complain about how boring the system looks and how Apple never improves its GUI.

    However, it shouldn't be resource intensive enough to slow down a 2013 MBP.
  3. bcam117 thread starter macrumors member

    May 1, 2012
    Thank you for you're answer. Yeah it probably isn't anything to do with the way Apple are implementing it. I just don't know way too much about these things.

    Sadly it does slow down certain things on my rMBP (nothing TERRIBLE mind you, but it did cost me over €2000 :p). It's "strange" that when on the nVidia GPU it doesn't seem very pronounced. I say strange because I haven't really noticed that much of a different between the intel one and nvidia when it comes to normal UI stuff on Mavericks. That said I might have just never noticed it.
  4. leman macrumors G3

    Oct 14, 2008
    The translucency effect is quite bandwidth-hungry, and the Nvidia GPU has much more of it compared to the Intel one. Apple is very clear about the performance cost in their developer documentation and urge the app designers to use it wisely.

    That said, I never noticed any substantial/experience distorting slowdowns on my 15" 2012 rMBP running integrated graphics. Even with its expensive composition effect, Yosemite is running much smoother than mavericks ever was.
  5. bcam117 thread starter macrumors member

    May 1, 2012
    That's cool about it being mentioned in the documentation. Could you share a link please? As I said I haven't noticed it in everything, but I have noticed it. I could upload a video or something, comparing certain UI performance aspects with the intel vs nVidia GPU active. Unfortunately I can't install mavericks anymore, well I don't want the hassle.

    Edit. I meant to say comparing UI performance with transparency on or off.
  6. sweebee macrumors newbie

    Dec 14, 2010
    I like Yosemite when translucency is disabled. Even a little more lag with it enabled annoys me.

    But this annoys me a lot:


    Hope apple will fix this :mad:
  7. Traverse macrumors 604


    Mar 11, 2013
    Because newer systems (at least 2012 and later) should be able to handle it seamlessly.

    Why? Because Apple thinks it needs eye candy that hinders usability but looks cool when you glance at them in the Apple store.
  8. MikhailT macrumors 601

    Nov 12, 2007

    Except that it is taking a lot of CPU resources as well, not GPU.

    Starting with DP5, it used to take up 20-30% of my quad-core i7 2.66Ghz constantly and went down to 10% on GM.

    I believe this is like the retina scaler issue, it's going to take another year or two for Apple to optimize it properly.
  9. leman macrumors G3

    Oct 14, 2008
    I don't think it is possible to optimise it even better, to be honest. I can imagine that additional CPU use comes from the need to having redraw more content, there is no way around it. At any rate, if your CPU is constantly >10%, something is definitively wrong. My usage is less then 3% on idle.
  10. MikhailT macrumors 601

    Nov 12, 2007
    Sure it is possible. They can offload it to the GPU entirely and they have already improved it if in the span of DP5 to GM.

    It doesn't take months to optimize this type of work, it take years.

    I've filed a radar and they confirmed it is normal (the 20-30% one back in DP5) based on current optimizations and will get better over time. They'll ship it at GM with this half-done optimization level and it'll get better in a year or two.

    Apple cares about battery life a lot and leaving the CPU at 3% on idle will eat up the battery life because it can't idle.
  11. SnowLeopard2008 macrumors 604


    Jul 4, 2008
    Silicon Valley
    Are you sure it's this bad? Constant 20-30% CPU usage? Battery life would be atrocious.
  12. leman macrumors G3

    Oct 14, 2008
    My understanding is that basically everything which can be offloaded to the GPU already is. The CPU overhead will always be there because the drawing thread must be executed on the CPU, and there is no way around it. Sure, it is always possible to optimise further, but at some point the diminishing returns are too high. Again, my CPU usage is under 3% If you have constant 30% load, there must be something wrong with your system.
  13. MikhailT macrumors 601

    Nov 12, 2007
    Read what I said: Starting with DP5, it used to take up 20-30% of my quad-core i7 2.66Ghz constantly and went down to 10% on GM.

    It's averaging about 10% right now on GM when I actually use my Mac. Apple's engineering team has confirmed to me that it is normal to see this high CPU usage and it will get better. There's nothing wrong with my system.
  14. w0lf macrumors 65816


    Feb 16, 2013
    Because transparency looks good and modern computers are more than capable to show transparent elements without effecting an average users performance.
  15. deviant macrumors 65816

    Oct 27, 2007
    the most important thing is..how will be battery life compared to mavericks. cause under mavericks my mba 2012 is at cool 5-7 hours. i love it. i'd really be disappointed if it became something like 3-4 instead..
  16. freediverx macrumors 6502a

    Feb 19, 2006
    If you could drop your display to 256 colors and VGA resolution I'm sure you could boost your performance even further. There are always tradeoffs between features and performance and historically speaking Apple has generally struck a good balance between the two.

    A 2013 rMBP is no slouch (I own one too), so I'm curious if you're experiencing performance issues in real life or if you're just running benchmarking apps and obsessing over the scores...
  17. MikhailT macrumors 601

    Nov 12, 2007
    GM 3 seems to be better, I don't know if it was intentional or not by Apple.

    WindowServer now seem to calm down better and quickly. Instead of 10% constantly no matter what I do, it's only 10% when I'm pushing it harder than usual. If I'm typing, reading and scrolling, it declines to 1-2%.

    If I do absolutely nothing, it is at 0.8-1.2%.

    I can't wait for the next Yosemite update, I suspect it'll be better.
  18. SmOgER macrumors 6502a

    Jun 2, 2014
    Personally, I haven't noticed any performance difference when turning the transparancy on/off. In places where it's laggy -- resizing finder windows or making finder full screen, scrolling in finder... It's similiarly laggy with reduced transparency. In other places performance is fine most of the time, regardless of that setting.
  19. robertosh macrumors 6502a


    Mar 2, 2011
    I feel the same with my old macbook. I'm happy with the performance that i get on a 4+ year machine, the system is perfectly usable and responsive.
  20. Beavix macrumors 6502a


    Dec 1, 2010
    On my Late 2013 rMBP 15" (Iris Pro Graphics) I see choppy graphics in two places:

    - When switching tabs in the About This Mac window (that's my "benchmark", currently the animation looks like it's rendered at 10 fps or so).

    - When the Open/Save windows appear on the screen with a zoom-in effect.

    The odd thing is, on my computer reducing the transparency has no effect whatsoever on that choppy animations, so I think there's actually a real bug somewhere in the system, not a slowdown due to transparency.
  21. bcam117 thread starter macrumors member

    May 1, 2012
    I noticed dropped frames when using the notifications panel with mission control and dragging certain windows around. I think it got better with GM 2. Shall try the 3 today. Again, my fears are stemming from iOS, where the "problem" is a lot worse.
  22. Beavix macrumors 6502a


    Dec 1, 2010
    In my case, seeing the Open and Save dialog windows stuttering when zooming in on the screen, a hundred times during a work day when I'm in a hurry, is really tiresome. Four months ago I bought a new rMBP for this?
  23. nudoru macrumors regular

    Feb 27, 2012
    Did you guys ever use OS X 10.0 on a G3 iBook? That was slow. It was several major releases before you could resize a window at >5fps. The translucency in Yosemite is nothing compared to that! :D

    I think it's really nice and love it even if it stutters a bit in some places - it'll get smother over point releases.
  24. ironman159 macrumors regular


    Aug 30, 2008
    Costa Rica
    I'm using a Macbook Pro 13" Late 2011, and just to get some perspective, this is using a HD3000 integrated card. The only place I'm seeing UI lag is switching tabs on the About My Mac window, not even in Mission Control or Launchpad. Yosemite is working great here (GM Candidate 3).

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