Since upgrading to XCode 10 my iOS simulators have become really slow. There's a lot of lag when scrolling in tableviews or scrollviews. Is anyone else having this problem? Can you elaborate? My MacBook is pretty much useless using the simulators. I think the point is that you are not going upgrade your MacBook Pro.
You are going to replace it. I remember the time, many, many years ago, when the iOS simulators were actually extremely light, fast and efficient. They could simulate in real-time, full 60fps, even on slower Macs. With every new version of Xcode, the simulators have become increasing slower. By this point they have become so slow that they are almost unusable. The Xcode 9 simulators were already really slow running at about 10 fps on this iMacbut now with Xcode 10 they have become even slower.
In fact, it's worse now because with Xcode 9 they were slow, but at least the framerate was quite steady and consistent. With Xcode 10 there framerate will fluctuate, between about 10 fps and something like 2 fps, at random intervals, making it almost unusuable.
I can't do anything else at the same time. II noticed a strong deterioration in the speed of execution of the simulator, now I'm working on the physical device because otherwise I can not work.
All worked fine when build for Also previous Xcode environments allowed us to configure simulators for various fallback iOS versions - I think. You might need to restart Xcode for it to notice the new simulator. Thanks for the tip Warp. Rolled back to Still a bit hesitant and jerky. May need to roll back further until At 2GB per simulator its annoying, as they were all downloaded before and existing on my machine before Simulators have become ridiculously slow.
Timing any kind of transition or animation is impossible.
I have tried every solution so far from changing FramebufferRendererHint to reinstalling simulators. I am about ready to go back to Microsoft world. Yesterday xcode 9. Absolutely insane. Slow to the point of being unusable. Yesterday, I was getting things accomplished. Today, I'm listening to my fans going into meltdown mode while the cursor slowly jumps across the screen.
I saw people had complaints about this in Beta but apparently they decided to release without fixing it, noting that there might be problems, or even acknowledging the issue. Experiencing the same issue here, especially from running Xcode Also contemplating installing Xcode I've encountered a lot more issues using iOS Anything iOS 11 and below seems to work okay, just not as fast as anything on Xcode 9.GitHub is home to over 40 million developers working together to host and review code, manage projects, and build software together.
Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community. Already on GitHub? Sign in to your account. I'm experiencing severe performance issues running my app against iOS simulators.
iOS 10.3 simulator very slow
They gradually become slower and slower which results in :. This happens daily now and on average I need to perform a-c approx 6 -9 times daily.
This is something that I used to experience when I worked with Xamarin and thought Flutter was a blessing but now its become a productivity nightmare. I can second this. The last time was actively developing with Flutter was with v1. Now I'm currently on v1. CPU usage shoots up and the app becomes laggy, slow, and my battery starts draining.
Unfortunately I can consistently reproduce the issue without animations i. Creating a simple RX based streamer app that does nothing but periodically produce a timer value that is consumed by a widget grinds iOS simulators down to a snail pace.
HH and uses a StreamBuilder to update the timer value. Additionally - for performance reasons, instead of wrapping :. Something as simple as this over time - you will see degradation. Additionallyeven if you open say iOS simulators, you will experience the slowness much faster - thus the only way to recover is to a kill off all simulators, b Shutdown VS Code c Do both, d Restart MAC.
Furthermore - I wrote the same simple app using both Xamarin. Native and Xamarin. I think there is something wrong with the iOS simulator in itself in debug mode. This should really be addressed. Backboard and Runner processes take over the CPU. Hi MsXam are you still experiencing this issue with the latest stable version of flutter?
Scrollinglist based data is particularly painful. Trying to create AppStore videos via the simulator is simply not feasible. Interfacing with the iOS simulators when debugging in Flutter consistently always means gestures get lost or abandoned You swipe, tap, pinch, etc and nothing happens - or you get delayed response and then try the gesture again.
The ONLY iOS simulator that doesn't exhibit this behavior is iPhone SE - this is very fast and now I use this for practically all development as the other simulators used with Flutter simply do not work. I dont expect this issue to be fixed anytime soon been opened since July - so just advise anyone to use the iPhone SE for the bulk of their development.
Thank you MsXam. I still don't believe this is specifically a Flutter issue. I know you are saying "But Xamarin and React-Native don't have this issue", that is because these frameworks use Native UI elements, the Flutter engine on the other hand uses the GPU to render anything on the screen. Go ahead a try to play any simple game, or open any native app that uses a lot of animations and see how you will have the exact same issue.
But bitkris-dev already said. So we agree on, that the iOS simulator lacks in performance. Still, flutter shouldn't become unusable as it is, because not everyone of us have the required physical devices for the app stores screenshots I have the same issue when running iOS simulator with couple of large background SVG files attached to the project.I try again. Same error. Try again. Googling around I can tell that I am not alone.
So if you are in a similar situation and for some reason need to download new iOS simulators outside of the normal XCode download process, here is how you do it. These steps worked for me, on my machine, but your results may vary and Apple may change things tomorrow and break this whole process. So good luck. The first thing you have to do is find the file that you need to download. Click the down arrow next to the simulator you want to download to begin the normal download process.
In this example, I am downloading the iOS 9. Now open up your Console. Once you are sure the simulator download has started in XCode, cancel it. When the download is cancelled, a new log will appear in Console with the url of the file that was being downloaded.
This is the url for the file you want to manually download. For my iOS 9. Now that you have the url of the file, you can download it however you like. I chose to do it through Safari so I could easily see the progress and resume the download if needed. So I typed the url into the Safari address bar, pressed enter, and watched the bytes start flowing in.
You can just as easily download the file using curl on the command line. Thanks to Google translate and some nice Chinese speaking personI was able to figure out the next step. You need to locate the XCode cache directory on your computer. Make sure you have not changed the filename of the downloaded dmg file. It needs to match the filename of what appears in the original download url. Now we need to tell XCode that the file is ready to install.Search titles only.
Some of them, like the iPhone X simulator are basically unusable. I was wondering if anyone else has the same problem. Same problem but with a Radeon card. Last edited: Oct 3, If I delete derived data, the project does not even build, which is really strange: Internal error. Please file a bug at bugreport.
Every time I tried to open the simulator that crashes immediately. Whenever I tried to run the simulator via Xcode then Xcode shows this error. Also, I tried to open the simulator directly and it's crash immediately. Here the gif gif is a little bit slow. Learn more. Asked 1 year, 6 months ago.
Active 7 months ago. Viewed 10k times. Whenever I tried to run the simulator via Xcode then Xcode shows this error Timed out waiting for the simulator application for iphonesimulator to become ready Also, I tried to open the simulator directly and it's crash immediately.
Vineet Choudhary. Vineet Choudhary Vineet Choudhary 6, 2 2 gold badges 40 40 silver badges 68 68 bronze badges. Have you tried to read the MacOS console log looking for relevant errors? Have U tried the solution from here stackoverflow. Similar problem resolved here - stackoverflow. Yep, in this case try to follow the link's solution. Active Oldest Votes.
This command should fix your issue close sim before and open after : sudo killall com. Vineet Choudhary 6, 2 2 gold badges 40 40 silver badges 68 68 bronze badges. Evgeny Karkan Evgeny Karkan 6, 2 2 gold badges 20 20 silver badges 34 34 bronze badges. I was switching between xcode 10 and 9. This fixed my problem. Thanks, man! Quit Xcode and restart then it worked! Mussa Charles Mussa Charles 1, 1 1 gold badge 7 7 silver badges 11 11 bronze badges.
Sign up or log in Sign up using Google. Sign up using Facebook. Sign up using Email and Password. Post as a guest Name. Email Required, but never shown. The Overflow Blog. Featured on Meta. Feedback on Q2 Community Roadmap.I did not. SourceKit crashing all the time also. However, i have noticed the same performance issues in other GPU accellerated programs. So far the new Xcode versions are not solving the issue.
I have been getting this problem on 3 different MacBook Pros with Xcode 8. The simulator runs so slow that it is practically unusable. I'm also meeting this issue on my Macbook 12 inch Not sure if it was because of mac 12 power or the software.
I tried to run Xcode 7.
Same for me. The iPhone 7 simulator is extremely laggy. Even pushing a VC on a navigation controller shows visible lag in the simulator. Well, the iphone simulator is also extremely laggy when running on my macbook pro retina 13inch I'm pretty sure the problem was there even before upgrading to macOS Sierra I remember hoping that the upgrade would fix the issue but it didn't. Reseting all simulators did not help I was very dissapointed when I ran an app in Xcode and found out the simulators are just as slow as they are on my 8 year old MacBook Pro.
Two other users with the same specs have the same problem as me, but a couple of other people on OSX Sierra with a different graphics card is working just fine. Starting the simulator is very slow, especially swithcin between iOS Devices e. I don't think this is graphics hardware related.
I just purchased a MacBoo Pro, and the issue remains. For future readers: this problem was fixed for me after updating to macOS Sierra I was suffering from this issue as well on my iMac, but on my Mac mini with much lower specs it ran smoothly. For me the culprit was that ' Optimize Rendering for Window Scale ' was turned off in the simulator menu under 'Debug'.
Once I turned this on, simulator performance improved dramatically! Edit: after a while the issue was back while 'Optimize for Window Scale' was still enabled. When I disabled and re-enabled this option the performance was fine again though. My company's iPhone and iPad devices is very limited so I must use iOS Simulator to test many UI and functions especially equipment compatibility with different dimensions.
But its laggy start speed give me a great disaster for debugging. I'm experiencing the same issue on Xcode 8 and Xcode 9 beta. I'm running on maxed out macbook pro.
This is a bit dissapointing.Xcode 11 includes everything you need to create amazing apps and to bring your apps to even more devices. Take advantage of SwiftUI, an all-new user interface framework with a declarative Swift syntax. Start bringing your iPad app to Mac with just a click. And with support for Swift packages, Xcode 11 lets you share code among all of your apps or use packages created by the community.
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Switch the design canvas to live mode to instantly interact with your running app in Xcode or on a connected device. Xcode makes it easy to get a huge head start on turning your existing iPad app into a native Mac app.
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