Xcode Canvas Simulator cause multiple diagnosticd processes to run and 100% CPU

Same issue here, MacBookPro M2 Max, Xcode 15.0.1

Here also, MBA M2, Sonoma 14.0, Xcode Version 15.0.1 (15A507)

Same issue here, MacBookPro M2 Max, Xcode 15.0.1. But it looks like the problem got solved with the macOS 14.1 update.

Same issue here. MacBook Pro M1 Pro, Sonoma 14.1, Xcode 15.0.1.

Same issue. Xcode 15 and 15.0.1 have this issue. Sonoma 14.0 and 14.1 makes no difference. The Simulator not only takes up a huge amount of CPU, but a huge amount of RAM. Crazy. Has no one at Apple noticed this??

uninstall iOS Simulator 17, install iOS Simulator 15 or 16. They will work fine. However, xcode requires iOS 17 installed, do not delete it.

**iOS is not the same as iOS Simulator. ** Good luck

Killing Poster processes, Springboard and diagnosticd fixed it for me. I expect it to reappear though. What an absolute pain.

I have to download the simulator for iOS 15.5 on iPhone 14 to prevent my macbook getting hot. Xcode -> Window -> Devices and Simulators -> Simulators -> + (bottom left) -> Device Type: iPhone 14 -> OS version: Download more simulator runtimes... -> + (bottom left) -> iOS -> iOS 15.5 Simulator. Yes its old ios but I dont want to drain my battery that fast and ruin the battery health.

I did a bit of profiling with instruments. Looks like we can't fix it on our side.

diagnosticd spending 35% on JSON parsing...

and SpringBoard simply cycling in the wait most of the time? trying to connect-disconnect - 25% ??

Hi there everyone, I just wanted to give you a headsup that this is not only happening locally but also big CI providers have this problem and are trying to mitigate the issue: https://discuss.circleci.com/t/severe-performance-problems-with-xcode-15/49205/110 The last post (https://discuss.circleci.com/t/severe-performance-problems-with-xcode-15/49205/110) gives hope that the issue will be resolved with Xcode 15.1...

I have the same (or similar) issue. SpringBoard getting over 100% CPU load and the computer is overheating when I launch Xcode. Workaround, which seem to work quite well, is to Force Quit SpringBoard in Activity Monitor every time I start Xcode session. Then the process is reinstated, but with the normal usage.

I run Xcode: Version 15.0.1 (15A507) My computer: MacBook Air M1, 16GB, macOS Sonoma, 14.1.1

I can confirm that the problem with Xcode preview still persists. However, with simulators, you can avoid this by selecting the GPU as 'Prefer Integrated GPU'

FYI: This is fixed in iOS 17.2, which is in Xcode 15.1