xcode 9 and it's emulator is too slow.

emulator, do you mean simulator ?

Too slow in which conditions ? Launch ? Execution ? Reaction to user inputs ?

Is it simulator itself that is slow or both XCode and simulator in your mind ?

Please be precise, your statement is way too general to be of any use.

It's all slow. I'm developing games using cocos2d-x and before in Xcode 8 I've got 30fps in my game and it was like playable in Simulator.

But with new simulators and Xcode 9 it's only 2-5fps, totally I can't now use simulators at all. iPhone X simulator specially slow... 0-1fps.

Launch and opening the simulator into your iOS app sometimes taks over a minute on a Touchbar 15" 16GB quad-core i7. Just upgraded to the release of Xcode (Version 9.0 (9A235) so we will see.

(Xcode, along with the rest of the Apple products, needs a menu item "Send logs to Apple Radar" and it should ask you for the defect report ID so Radar attaches it to your bug report when it gets sent.)

So I thinkk it's worth filing a bug report, all those who have faced the problem.