Mission Control Lag in Lion, iMac

First restart then try the Reset OS X cache system trick. Close any running programs the launch /Applications/Utilities/Terminal and run the code:
Then don't close Terminal until you get another Terminal prompt. Then the reset is completed. See if this helps.

I have had the same problem.. Not very Apple like if you ask me.. I don't know though, I have been quite annoyed by it.

Are you by chance running a system that was in-place upgraded from Snow Leopard? If so, I've noticed similar on my 27" i7 iMac. My 21.5" i5 iMac (2011) is smooth as butter, though. However, it's running a fresh install of Lion - no in-place upgrade.

Were I in your position, I would back up your media to an external hard drive and do a format -> fresh install of Lion. Don't do a Time Machine migration of your existing install, or you'll defeat the purpose. I have a sneaking suspicion that issues of this nature relate to the convenient, (but flawed) Snow Leopard -> Lion upgrade through the App Store.

sylvantemplar said:

Are you by chance running a system that was in-place upgraded from Snow Leopard? If so, I've noticed similar on my 27" i7 iMac. My 21.5" i5 iMac (2011) is smooth as butter, though. However, it's running a fresh install of Lion - no in-place upgrade.

Were I in your position, I would back up your media to an external hard drive and do a format -> fresh install of Lion. Don't do a Time Machine migration of your existing install, or you'll defeat the purpose. I have a sneaking suspicion that issues of this nature relate to the convenient, (but flawed) Snow Leopard -> Lion upgrade through the App Store.

Click to expand...

I believe it doesn't happen to your 21.5" iMac because the screen resolution is only 1080p while the 27" is 1440p (which is around 4x more pixels). When my MBP 15" 6490m is connected to a 1440p display, MI tends to "lag" after some hours of usage but when I unplug the 1440p display, MI reverts to a silky smooth state.

Same problem since yesterday.

Sadly, this started happening to me yesterday. It was all fine a few days ago.

I did sometimes (since I bought it) noticed a little lag *a little*... minimal, but I could notice it because it wasn't as smooth as when I had no running applications.

And now...Mission control is slow and laggy... any fixes?

I'm using a 2011 13" MBP i5 and 8GB RAM with OS X Lion.

So did anyone figure out a definite fix for this? This just happened out of the blue to me.

I'm running 10.7.4

I am experiencing something similar and also searching for some kind of resolution.

I have a 27" i7 iMac with the Radeon 4850 card, 8GB of RAM and a Corsair SSD. This thing is a rocket, and yet I get occasional lagging of gestures for mission control.

For example, sometimes I will do the four finger swipe on my magic track pad, and for several seconds the screen is just frozen and then I will get mission control or app windows to come up.

It's rather annoying, even more so because of how fast the computer is otherwise.

jmpage2 said:

I am experiencing something similar and also searching for some kind of resolution.

I have a 27" i7 iMac with the Radeon 4850 card, 8GB of RAM and a Corsair SSD. This thing is a rocket, and yet I get occasional lagging of gestures for mission control.

For example, sometimes I will do the four finger swipe on my magic track pad, and for several seconds the screen is just frozen and then I will get mission control or app windows to come up.

It's rather annoying, even more so because of how fast the computer is otherwise.

Click to expand...

Download and run Xbench, but unselect "Thread Test" in their dialog box. For some reason Xbench hangs on Lion so the fix for it is to unselect thread test.

This worked for me.

ayala421 said:

Download and run Xbench, but unselect "Thread Test" in their dialog box. For some reason Xbench hangs on Lion so the fix for it is to unselect thread test.

This worked for me.

Click to expand...

Running Xbench fixed your problem, or unselecting thread test changed a setting in Lion that fixed the problem?

Running Xbench fixed my problem.

I ran Xbench but I'm curious about how it could fix anything, it's just a benchmark program.

I can second this. Been having this issue with my MacBook Pro (Santa Rosa) since Lion came out. I even wiped my drive and installed from scratch to try and fix the issue...

After months of being annoyed, xbench has fixed it. I just ran it once with the thread test unchecked.

Back to normal.

THANK YOU ayala421!

jmpage2 said:

I ran Xbench but I'm curious about how it could fix anything, it's just a benchmark program.

Click to expand...

Honestly I have no clue, but my assumption is that xbench forces your video card to clear the lag out.

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Payton said:

I can second this. Been having this issue with my MacBook Pro (Santa Rosa) since Lion came out. I even wiped my drive and installed from scratch to try and fix the issue...

After months of being annoyed, xbench has fixed it. I just ran it once with the thread test unchecked.

Back to normal.

THANK YOU ayala421!

Click to expand...

Your welcome

Okay, fair enough. Reboots in the past though haven't cleared it. I mean, it will not happen 100% of the time, it will just spontaneously sort of freeze up and might not do it for another day or a week then it will happen again. I will do the gesture on the trackpad for expose/mission-control/spaces and it will simply stop responding then after maybe 5-10 seconds it will respond again and whatever gesture I had been doing will suddenly "activate".

(First time using the forums here, so sorry if formatting is wrong or something like that).

To the Mission Control Lag, I have experienced this myself. I have the late 2011 Sandy Bridge 15 inch Macbook Pro with the 2.4 ghz i7. All was working great until one time when I turned it on and everything was lagged as Ive read about here. I tried a bunch of things listed on here, xbench, graphics stress test, resetting smc, all that other stuff. I took it to the apple store and after dealing with a few different people I realized there was nothing they were gonna do except tell me its a "core OS problem".

After a complete reset of lion it worked fine, haven't had a problem in several months. But for those interested, a reset of lion will work.

By 'resetting' Lion I am assuming you mean that you did a from-scratch installation? Did you restore from a TM Backup afterwards?

I'm getting this almost every time on a current gen mac mini.
I even just upgraded it from 4 to 8GB ram but still does it.
Any hot corner action (show desktop/show all windows/show widgets) is a 3 to 4 second delay.

I have Macbook Pro retina 2.6GHz Core i7 with 16GB RAM. It basically top of the line model, but mission control is very laggy. It can even takes 3-4 secs before opening. Unbelievable!!

I also had Mission control problems and tried numerous fixes and nothing worked. I finally decided to erase the OS partition and reinstall the Lion via internet recovery. This fixed mission control and strangely the iMac now runs much much faster than it did the day I bought it.

I have this problem too but it's only when I'm running more than 2 programs. Maybe it's because my ram is only 4GB. Who knows.

With Mountain Lion this problem has only occurred a couple of times. It is definitely related to the number of window items I have open, so I suspect that it is related to the amount of memory available in either the machine or the graphics card. I do have 16GB of RAM and I do have a higher end Radeon in my 27" i7 iMac.

Don't know if this helps anyone, but since I finally found a way to fix those Mission Control lags for my iMac and I'm happy again i just wanted you guys to know what I did:
It was the application frame mode of photoshop (or maybe all the applications within the Creative Suite...) that caused the laggy Mission Control animations at my iMac.
I tried all the other hints with dock animation, xbench, cleaning of cache, re-installing the OS and so on before - nothing worked. But as soon as I deactivated the application frame in Photoshop CS6 (Windows - Application Frame) everything went back to normal.
Hopefully this information is at least helpful for some of you guys

Volkward

I had headache with this mission control lag until I found this thread! Amazingly xBench fixed it for me, thank you alot, saved me time not having to reinstall OS.