Q: Mountain Lion UI Lag on rMBP !!! (Let's Make this thread serious and hope for a fix)

Discrete Graphics has helped a little, especially when running scaled outside of Retina.  But Chrome is still really choppy as I'm using it right now.

Really crossing my fingers that this is a software issue and a fix will come in time.  I don't expect this from an Apple product.

From the google chrome group site:

Open chrome://flags/

Enable 'GPU compositing on all pages', 'Threaded compositing', close all window and restart Chrome, you will find the problem has improved a lot,but still not as good as Safari.

This has fixed the choppiness with Chrome on some sites, however, there are still many sites that are still incredibly choppy such as:

http://arstechnica.com/

http://pitchfork.com/

Pretty sure it is something wrong with Mountain Lion that needs to be fixed... I have the same problem on my mid 2010 MacBook white unibody with 8GB RAM and 256 GB SSD.

Thanks for that Chrome fix.  Yeah I just opened Safari and it is blazing fast.  It's also improved a lot since version 5, still doesn't have the usability I like in Chrome though.  The Chrome fix has improved the lag immensley to my delight (what a creepy word).

Back here for an update: I just ask for a return of my Macbook Pro Retina 2,3 - 8GB and a deliveryman will take it on Monday I think. Then, I will switch it for a Macbook Pro 2012 2,6 - 8GB. At least, I'll be able to improve my RAM without selling the whole machine, add a SSD drive, and be certain of its reliability.. That was I expect from an Apple product, and I made a big mistake by grabing this new stuff with a Retina display not optimized with the whole system. That's the first try of Apple with this kind of display on a Mac, and they didn't aticipate that a machine like that will require so much more performances. I think I'll wait 2 or 3 years before bying a Mac with Retina display : when all will be optimized for. That's the first innovation, I tried it but I haven't been sastisfied and will wait a couple of year.. I trust in the classic version because they proved their effectiveness.. That was my story !

I get scroll lag too...

Hardware:

Late 2009 MBP

Intel Core 2 Duo 2.8 Ghz

8 GIGs RAM

256 MB Crucial SSD with forced TRIM support

Clean update to Lion about two months ago, Updated to Mountain Lion by overwriting Lion (Not clean install).

It's the OS, not the hardware.  It suprises me they released the OS with this issue, they must have run across it in testing I would think...

It couldn't be a hardware problem because everything was running perfectly under Lion (well, except Safari...).

I just think Apple is using GPU for too many animations... and we all know OS X Graphic Drivers are ****** so it doesn't help...

A little information :

- I made an update from Lion to Mountain Lion => I got lag with Mission Control

- I made a Clean Install creating a new partition (so I'd 2 OS X on my SSD ) => I got lag too

- I made a Clean Install erasing all the SSD => well... it's a little better... but only a little... the only changes are some Mountain Lion's bugs who disapeared... But lags are still here...

I really think an update'll come to correct the issues... I tried 10.8.1 with an other MacBook Pro (not Retina) and i seems that memory's management is a little better. We gonna see if the final version of 10.8.1'll solve our problem or not...

Good infos buI'mi still think that 10.8.1 will be not the soluzion.

I hope I have mistake.

I don't think 10.8.1 gonna solved our problems... But Maybe 10.8.1 gonna be Much more important That it actually is... (Bugs solved + Facebook integration + Maybe new surprises like a Maps OS X )

I am experiencing a huge lag when browsing Facebook...

I have 10.8.1 update and it definitely not helps.. It's exactly the same !

I am also experiencing this problem. Most notably when i open pdf. files that i must read (for my university work) and i try to scroll around in them. I was excited to switch to Macs, this being my first purchase. Unacceptable for a $2500 machine.

I will be returning this.

Same here (MBPr 2.6 GHz, 16 GB). Even after clean-installing ML ... The joke is: my iMac (Early 2008) runs butterly smooth now with ML (with Lion he didn't, all the animations stuttered). So, it must be a software problem, I guess.

I really hope Apple will fix this annoying issue.

When I'm using Eclipse, the 650M GT seems to be enabled : it doesn't lag anymore. I really think HD4000 drivers need to be upgraded...

I went to Best Buy yesterday to see for myself the lag that people are reporting because I am debating whether to get a rMBP or a MBA.  At Best Buy, I was able to compare a 2012 MBA and a rMBP, unfortunately both were running Lion.  Automatic graphic switching was enabled.  I did notice lag on the rMBP doing a lot of basic things in the OS that I did not see on the MBA.  One place I really noticed it was in the App Store, scrolling up and down on the featured apps page did not feel smooth on the rMBP, especially the animations that occur when you reach the top or bottom of the page (when the page sort of springs up and down).  Scrolling in Safari felt much smoother on the MBA as well, I tested some of the notoriously bad sites.

My verdict is that the rMBP has a hard time with the new resolution.  Unless Apple can optimize the OS to make the animations smoother, or the drivers get a magical update that help things out, I think we are going to be stuck with these problems.  I just think that it is a hardware limitation with the rMBP and the resolution it runs at considering how much smoother the MBA was in the same configuration.  I wish I could have turned off automatic graphic switching and did a comparison that way.  I wish someone like CNET would do a high quality video comparison between a rMBP and a non retina mac laptop (running Mt. Lion) using the various settings to really quantify the problem.

That is my 2 cents.