iOS 11 Simulator unusable slow

Unfortunatly, the problem persists in XCode 9.1 Beta.

Hope this helps someone. I was having the same issue with Xcode 9 GM and unticking the below Simulator option fixed it for me.

Simulator Menu > Debug > Slow Animations (untick)

For me the same, open Simutalor load OpenGL objects and Emulator cpu rise to 150%, really... i use device to test.. but sometimes quickfix via simulator helps.. Now is unusable.

Dude, that is so disheartening to hear.

Really hope they don't miss this in the next update.

I faced to this problem too. All my OpenGL applications slowed down by iOS11 Simulator after Xcode9 beta 4.

The reason is Simulator's OpenGL.framework which is contained in Xcode9.

I swaped the Simulator's OpenGL.framework with Xcode9 beta 3's OpenGL.framework.

All my OpenGL applications work as prevous now.

Hey, can you upload libCoreVMClient.dylib from Beta 3 somewhere? Thank you vey much!

An update. Still haven't solved things, but the problems I had creating the diagnose reports were because I hadn't run xcode-select to cause xcrun to reference the Xcode 9 installation.

I've been able to create a bug report now, #34737584.

Hi mixer555,

Here, you can get it.

https://www.dropbox.com/s/1bdyh86eo01x2em/libCoreVMClient.dylib?dl=0

When I replace that file with the one provided for download I get a "EXC_BAD_ACCESS (Code Signature Invalid)" upon launching the iPhone X Simulator.

You should be able to get it from developer.apple.com still.

Yes, we are aware. It's a top concern for us (and has been since it was originally reported about 2 months ago). Unfortunately, the OpenGL team did not get a fix in time for 9.1 Beta 1, but a fix for the performance issue will be available in an update soon.

It looks like you *copied* the file into place, which will cause it to keep the same inode. The new contents will fail to match the old signature. You can address this by using 'mv' instead of 'cp' or deleting the old file first. I suggest you just reboot to clear the cache.

Replacing the file helps, thanks! But Apple, please fix this in the Xcode 9.1 GM.

Where should I put the new libCoreVMClient.dylib?

This is probably because you have the wrong Xcode selected with xcode-select.

I'm pleased to report this bug is fixed in Xcode 9.1 beta 2.

MKMapView interactions are better, but still much slower on iPhone X iOS 11.1b2 simulator than iPhone 7 iOS 10.3.1 simulator.

The Simulator uses a software-based OpenGL renderer so its performance will be poor.

Specifically, the MapKit in iOS 11 makes heavier use of OpenGL than the version in iOS 10.3. Since the simulator is currently limited to CPU for all rendering, that extra burden translates into lower framerate.

The issue that was fixed in 11.1 Beta 2 was the bug in OpenGL itself that was preventing JIT from being used.

If you feel that the current state (even with the OpenGL fix made in beta 2) is not good enough for development, I strongly urge you to file radars.

I have the same question

please explain how to replace the file. Through terminal? please give the syntax!

You don't need to anymore. Grab Xcode 9.1 beta2

It works a treat from what I've seen so far.

It will be even better when 9.1 is released formally though so that we can sign our binaries for submission.

@jeremyhu

Thanks for these updates. Really pleased to have 9.1b2 to test with. I can now get stuck into all my updates.

Is there anyway to get iOS 11 Simulator running in Xcode 8? It seems Xcode 9 is so buggy and simulator for iOS 11 doesn't work that the logical thing to do would be to run it in Xcode 8. But I can't find any docs on how to do this...only docs on how to support iOS 11 for device builds, not simulator builds.

If anyone knows, please show me the way.

My advice would be to download and install Xcode 9.1 beta 2 from the member center. The ios11 sim in that works fine (for me). I’ve got the 9.0GM installed now for binary signing and 9.1b2 installed for testing and debugging.