Xcode 12.4 Performance

I'm also facing same issue. Started using Xcode 12.4 on macOS Big Sur on a decently large project. The CPU chokes to 200% using about 3GB of real memory making my entire machine freeze during project compilation.

I'm also having the same issue with Xcode 12.4 on macOS Big Sur 11.2.

I'm also facing the same issue. Xcode 12.4 on the latest macOS (11.2) freezes 2-3 times per minute. It's true that my MacBook is old (Late 2013, i7, 16GB RAM), but I didn't face it with Xcode 12.3.

Workaround:

1. open Devices and Simuators (shift + cmd + 2)

2. turn off Connect via network for each device

I've been having the same issue. I updated Xcode to 12.4 and it's been going extremely slow ever since! I'm on a 2020 M1 8GB.

Same issue. MacOS 11.2, and Xcode 12.4, on a MacBook Air M1. It has made Xcode unusable, can't click on anything or edit text. If it does work it works for a few seconds and then locks up again.

I've tried deleting the Xcode cache, and deleting Xcode and then redownloading it from the App Store

Hopefully it will stick because I have wasted a tremendous amount of time around this issue, Carrione solution above about turning off connection to devices via network for me so far. After clearing my phone from the devices window I was able to connect and run my app on it again

Same issues here... Development has become unbearably slow since build time increased with this version. Build process seems like freezing on the last steps and it doesn't proceed for a few good minutes before finishing (MacBook seems to be doing little to no computations at that time, looks just like idle). Unit tests take much longer to launch too. Every new build launched takes almost the same amount of time no matter how many lines of code have been changed, you change one line and wait five minutes no matter if there was a build earlier or not. Xcode 12.4, macOS big sur 11.2.1, MBP 2020 16GB i5

Ditto. Total insanity... FIX THIS, Apple!!!
Disabling network connection also seems better for me, so far.