iMac 5K Retina extremely slow Mission Control

You really thing this is ok ? On the movie undoubtedly we can see a great improvement but it's still jaggy in some cases. This is only system UI. It cannot be jaggy in such powerful computers.
I think that apple sold bad hardware in some batches but they don't want to admit.

I gave up my new iMac 5K with i7 and SSD to the service because comparing to weaker model with fusion and i5 it was working terrible. Apple authorized service told me that no hardware test shows the problem but the issue with iMac is undoubted. Now I'm waiting for another pack of apple tests and some reasonable solution from apple.

I'm working on apple hardware almost a decade but if they selling hardware with software that is not reliable, I will demand refund.

Maybe it's time to say goodbye to old good apple times, where OSX was stable and fast and hardware quality impressive. Maybe El Captian will give us blue screens ? If they cannot make expose work properly ? 🙂. This is so sad 😟.

I know this is an old thread, but I figured I'd share what I did to solve this (and no, I didn't read through the entire thread, so I'm sorry if this is not new info).

I used TinkerTool and Secrets to turn off every animation possible and now this system is snappy like it should be. I also turned off some animations from the command line (there is probably overlap but I didn't check). Also, cut down on transparency and blurring in apps that can, like iTerm2.

# disable Misson Control animations

defaults write com.apple.dock expose-animation-duration -float 0

# opening and closing windows and popovers

defaults write -g NSAutomaticWindowAnimationsEnabled -bool false

# showing and hiding Launchpad

defaults write com.apple.dock springboard-show-duration -float 0

defaults write com.apple.dock springboard-hide-duration -float 0

# showing the Dock

defaults write com.apple.dock autohide-time-modifier -float 0

defaults write com.apple.dock autohide-delay -float 0

killall Dock

I can confirm that El Capitan completely fixes this issue. 100%. They take a totally new approach to mission control and everything is much snappier.

I can confirm that problem is solved on el captain. Last week after one month of my new iMac 5k analysis done by apple engineers the answer was that my iMac is ok but they have issues with firmware. I doubt in that. I thing that they just release broken software and now the don't want to admin.

Thankfully before returning imac to store I have ask them to install el captain. On developer preview everything was working as it should. So now we need to wait for stable release. Shame you apple.

Right now i upgraded to the first public beta of El Capitan 10.11 and can tell, that all the discussed "slow motion effects" in Mission Control and window behavior are gone on my 5K i7! At least as i can tell in these first hours …

Success at last, it's a thumbs up vote from me too running El Capitan OS X 10.11 (15A215h) on a refurbed base model 3.5 GHz Intel Core i5/AMD Radeon R9 M290X. Mission Control, switching Desktops, and scrolling is super smooth and usable, just like it used to be in the good old days. At last I can be happy with my iMac 5k, and although I contemplated it many times, I'm glad I didn't go chasing the error and ploughing more money unnecessarily into the i7/M295X.

It this moment we are running on OS X 10.10.4. The problem is still there!

Although there's some improvement: we do not need to use the 'Increase contrast' button anymore, only the 'Reduce transparency'.

No more ugly borders.

The only other trick I had to do to get the iMac running smooth, was log out and log in again after checking the 'Reduce transparence' in the Accessibility screen.

It must;ve been a bug. I actually had to turn on "increase contrast". But they HAVE FIXED it in the new release of OS X El Capitan, so just update your machine and it'll go back to normal 🙂

unfortunately, System Integrity Protection (SIP) in El Capitan breaks some software that i need; like TotalSpaces, which is far superior to Apple's Mission Control. so i either have to put up with the sluggish GUI in Yosemite, or 'upgrade' to El Capitan, and say goodbye to some programs i enjoy using. there is a workaround (disable SIP), but i'm not going to bother. and i'm really getting sick & tired of Apple using us all as beta testers.

Well I'm running OS X 10.11.3 on an iMac 5k, 16GB, R9 M290X and Mission Control and switching between apps on different desktops is extremely slow and laggy. When I resize the larger windows (to be very small) it runs smoothly just as a lot of people here described. Any further insights?

It's 2017 and I still have the same issues, lagging mission control animations still stands even after Sierra is here, is there any permanent solution or should I just give up?

Sierra fixed it for me, although still not perfect, it's much better. Maybe High Sierra will fix it for good because they're using Metal for Mission Control.

Edit:

If coarse I have installed lates OS by now.

Took every update that was available in the last half a year.

But still having the same problem.

Regards

Klaus