UI lags when using dGPU

[zeed2001]

My device is RMBP 15' -the end of 2013，10.11 GM has been installed。When GT750M is running and if i click the Download stack ，you will find a noticeable choppy animation of fan-shaped unfolding process，but when Iris pro is running，every thing goes smoothly as butter。You will even find more UI animation such as minimizing windows choppy ONLY JUST when GT750M is working，Irs pro is fine。
Its odd that GT750M performs worse than IrsPro。Do you guys have the same issues as mine？

 

[jeanlain]

Strange... I can't test it myself but it could be due to the fact that the nvidia GPU doesn't use Metal for the UI animations.

 

[beebarb]

Strange... I can't test it myself but it could be due to the fact that the nvidia GPU doesn't use Metal for the UI animations.

That's not entirely true afaik, only certain cards that can be installed in Mac Pros have that issue.

 

[zeed2001]

That's not entirely true afaik, only certain cards that can be installed in Mac Pros have that issue.

I thought Metal might be the key point because 10.10 has the opposite symptoms：GT750M runs far more smoothly than Irs Pro although neither of them reaches the level that IrsPro does under 10.11.

 

[jeanlain]

That's not entirely true afaik, only certain cards that can be installed in Mac Pros have that issue.

Yes the Kepler cards don't support Metal at all. I mean that nVidia cards (and AMD cards) don't use Metal to accelerate the UI. Only intel cards do.

 

[zeed2001]

Yes the Kepler cards don't support Metal at all. I mean that nVidia cards (and AMD cards) don't use Metal to accelerate the UI. Only intel cards do.

OH no，when using external display it will be forced to switch to GT750M,so the suffering must be taken?

 

[jeanlain]

This is just a theory. Maybe there's an issue with your specific install that may be solved in an update or by reinstalling. The 750M should be fluid at animating the UI, even without Metal (it uses openGL).
And it's likely that all GPUs that support Metal (including the 750m) will eventually use it for UI acceleration (maybe in a 10.11.x update). I don't see why Apple restricts these GPUs to using openGL in system apps and core graphics, but these cards support Metal just fine.
More info at http://netkas.org/?p=1410

 

[Beavix]

From the ArsTechnica review:

Apple tells us that the [Metal] Core Graphics and Core Animation acceleration is available only on Macs that use Intel integrated graphics exclusively. It’s not available on higher-end Macs with dedicated GPUs or in laptops that switch dynamically between integrated and dedicated graphics.

 

[baryon]

From the ArsTechnica review:

Damn, that's not cool. But why does that cause worse performance than on Yosemite in OP's case?

I have the same computer so I'm quite worried about upgrading - I suffered for several months with Yosemite with its UI lag issues that were only fixed in 10.10.3, and I'm not ready for that again! I'm thinking that waiting for 10.11.3 is a good idea?

 

[zeed2001]

From the ArsTechnica review:

This maybe the ultimate answer !

 

[Blue Sun]

From the ArsTechnica review:

I find it unacceptable that the more powerful and expensive Macs with both the Iris Pro and dedicated chip don't get Metal support when GUI animations are concerned, but Macs with only the integrated chip do. That simply is not fair. Will my late 2013 15" rMBP with the GT 750m have more dropped frames when using the Iris Pro for Mission Control and other animations because of this? If so, I will not be happy.

 

[jeanlain]

Whether it makes a noticeable difference remains to be seen. The OP's problem has not been reported by others, AFAIK.
Metal mostly matters for games and pro apps.

 

[zeed2001]

Damn, that's not cool. But why does that cause worse performance than on Yosemite in OP's case?

I have the same computer so I'm quite worried about upgrading - I suffered for several months with Yosemite with its UI lag issues that were only fixed in 10.10.3, and I'm not ready for that again! I'm thinking that waiting for 10.11.3 is a good idea?

I find it unacceptable that the more powerful and expensive Macs with both the Iris Pro and dedicated chip don't get Metal support when GUI animations are concerned, but Macs with only the integrated chip do. That simply is not fair. Will my late 2013 15" rMBP with the GT 750m have more dropped frames when using the Iris Pro for Mission Control and other animations because of this? If so, I will not be happy.

Sadly YES。。。。。。

 

[MaciMac100]

Sadly YES。。。。。。

This feels dissapointing.

 

[leman]

I find it unacceptable that the more powerful and expensive Macs with both the Iris Pro and dedicated chip don't get Metal support when GUI animations are concerned, but Macs with only the integrated chip do. That simply is not fair. Will my late 2013 15" rMBP with the GT 750m have more dropped frames when using the Iris Pro for Mission Control and other animations because of this? If so, I will not be happy.

Support will most likely come later. It makes sense to test these things one case at a time and solve challenges as they occur. Metal in UI is more about power efficiency than anything else, really. El Capitan's UI drawing (especially in Mission Control) has been substantially optimised, and performs very well using the standard OpenGL path.

 

[Beavix]

El Capitan's UI drawing (especially in Mission Control) has been substantially optimised

They also simplified Mission Control in El Capitan and got rid of some graphic effects which were CPU/GPU-intensive in Yosemite.

 

[nontroppo]

I can't confirm this (OP) behaviour. Using the latest Quartz debug (Sept. 16th) to switch GPUs and measure framerate, both iGPU and dGPU hit 60fps which clicking the "fan" download stack repeatedly. I think I sometimes see a stutter at the first opening (Apple cache the icon previews but it gets cleared every so often then you get a grey cloud in the icon's place while the preview is generated which I think causes this stutter, why it is non-deterministic), but it happens non-deterministically both on iGPU and dGPU, sometimes more on one than the other but it isn't consistent. Switching iGPU and dGPU I see no difference in MC animation (50fps max gesturing through spaces as fast as I can), and both hit 60fps using Launchpad. Everything is really smooth overall...

2015 rMBP with AMD R9 + Iris Pro and 10.11.1 beta 1 which we've now learn't doesn't use Metal for any UI drawing...

edit: wrote 750m but my dGPU is actually the AMD M370X

 

[leman]

They also simplified Mission Control in El Capitan and got rid of some graphic effects which were CPU/GPU-intensive in Yosemite.

I believe there is more to it. The (quite crazy) thing about Mission Control is that it reflects all UI changes in the individual windows in real time. THAT is CPU/GPU intensive. And they seem to have improved their algorithms dramatically. Right now, I have over 30 windows open, and Mission Control is absolutely smooth even though many of these windows are running animations. This was not the case before. You can't explain this one by removal of blur or some other effect, these are fairly cheap in comparison.

 

[Yaboze]

I have a MBP that doesn't support Metal at all, but that stinks for people who have supported machines. I just read that article and at least you CAN use Metal for games on either GPU (integrated or dedicated), just not for the UI.

 

[Blue Sun]

Support will most likely come later. It makes sense to test these things one case at a time and solve challenges as they occur. Metal in UI is more about power efficiency than anything else, really. El Capitan's UI drawing (especially in Mission Control) has been substantially optimised, and performs very well using the standard OpenGL path.

I'm hoping that this is the case. It makes sense to use a unified Metal system for machines that can support it. Switching between OpenGL and Metal depending on the app open seems strange. Then again, I'm not a programmer and really have no clue how these sort of things are implemented.

 

[baryon]

So, other people with Retina MacBook Pros (from late 2013 ideally), are you seeing any kind of UI lag compared to Yosemite? I just hate UI lag and I remember Yosemite had it until 10.10.3 or something, and it really pissed me off. I'm not updating until I can be sure that won't happen again!

 

[zeed2001]

I can't confirm this (OP) behaviour. Using the latest Quartz debug (Sept. 16th) to switch GPUs and measure framerate, both iGPU and dGPU hit 60fps which clicking the "fan" download stack repeatedly. I think I sometimes see a stutter at the first opening (Apple cache the icon previews but it gets cleared every so often then you get a grey cloud in the icon's place while the preview is generated which I think causes this stutter, why it is non-deterministic), but it happens non-deterministically both on iGPU and dGPU, sometimes more on one than the other but it isn't consistent. Switching iGPU and dGPU I see no difference in MC animation (50fps max gesturing through spaces as fast as I can), and both hit 60fps using Launchpad. Everything is really smooth overall...

2015 rMBP with 750m + Iris Pro and 10.11.1 beta 1 which we've now learn't doesn't use Metal for any UI drawing...

I installed the latest Quartz Debug and did the same thing, and i snapped following tow pictures
as shown. There's at least 9 frames dropping on dGPU mode when rapidly clicking the Download Stack at a very high frequency , human eyes can tell this easily but not so dramatically as what happens contrarily in Yosemite(dGPU runs much smoothly than iGPU does).
PS:Misson control and LaunchPad runs both smoothly under two different GPU modes.And my system is the very same as yours-10.11.1 Beta (15B22c).

IrisPro:

GT750M:

 

[nontroppo]

Hm, so your machine shows a difference and mine doesn't — perhaps that depends what is in the downloads folder?

Try moving everything out except a couple of simple files and see if the performance difference changes. This seems the most likely candidate as the icon previews could be causing a slowdown from 60fps...

p.s. I worte my machine was a 750M that was typo, actually my dGPU is the M370X, so perhaps this could depend on the NVidia vs. AMD drivers...