xcode 9 (9A235) horrible performance...

So i updated xcode to 9 after seeing this in the app store


The source code editor has been completely rebuilt for amazing speed. It scrolls at a constantly smooth rate, no matter the files size.


wait

what

cause for now im just force quitting every hour when everything freezes over


swift code highligth/completion is still broken.

and speed is still amazingly super slow.

oh and opening a storyboard still takes forever


someone needs to explain to me how can an editor become so useless


I miss the days i was working with visual studio 😟

Replies

I am having the same problem...everything is excruciatingly slow. Building, simulator, indexing, everything takes forever...I miss XCode 8 and swift 3...

I wonder why some people are not having the problem, but for me the editor is almost unusable.

There must be a reason, something that I can fix.

If anyone has any idea, let us know... 😟

On Edit:

Oh, and it seem to use the battery twice as fast...maybe I am mistaken, and doing something wrong. But I don't know what it could be.

Happens to me too. And it builds every time i type, every keystroke generates a new build process. Never happened in any previous version, it did right after updating. Almost unusable.Any way to fix? To improve?

Slow for me too. Editing swift files, very laggy. Copy and paste of swift code terribly slow. Opening a moderately complex Storyboard, takes forever.


SourceKitService takes 100% of CPU at all times.


radar://34564276

Same issue .... Terrible user experience ....


This issue lower my productivity....

Yes, same issue here. This is the first Xcode major release that I'm so disappointed in. Xcode 9 beta 3 and earlier is fine but started to have this sluggish editor issue after beta 4, thought GM will fix this issue but apparently not.


I have to use last release Xcode 8.3.3 to edit code and then use Xcode 9 to compile for new iOS 11 features. Hope Apple needs to fix this issue as soon as possible as lots of poeple has such issue, not productive with Xcode 9.

I have been seeing the same since the Mac App Store updated my Xcode installation from the GM_seed version to the App Store version (they carry the same version numbers, though). Source code completion, coloring, and Quick Help degrade rapidly and then fail.


I found three fixes:

  1. Close the project and reopen it. This reenables Quick Help and gives you a few instances of code completion. Unfortunately performance degrades again after a few edits.
  2. Never open the Quick Help Inspector. Code completion and coloring still degrade, but at a slower pace.
  3. Unpack Xcode.app from Xcode9_GM_seed.xip, rename it, and then install it in the Applications folder. This version works as expected.

Unfortunately, the GM_seed file is not available on developer.apple.com/download anymore. I was lucky enough to keep it around, you may still find it in your Trash folder or on your backup. Beta 6 also still works.


I filed my observations on radar://34572882.


Some APIs on the simulator, like SceneKit, are still very slow, but this was the case since a few beta versions back.

Extremely slow here, only while editing storyboard, either simple or complex. Takes forever to accomplish any change.

Observations of Xcode 8.3 vs 9 on a 12-Core 2012 Mac Pro...


  1. Opening projects with tabs (to organize your various windows) - Speedy on 8.3; painful on 9. During the time I spent with 9, I chose to close all additional tabs. The more tabs you closed, the faster Xcode 9 performed.
  2. Storyboard - both 8.x and 9 suffer in slow loading. Seems a bit worse though in 9.
  3. Editor windows. Xcode 9 the clear winner here. Very fluid. 9 also fixed the bugs dealing with your code scrolling on its own as you near the bottom of the file.
  4. Builds - without doing detailed timings, feels the same.
  5. Indexing - Same or improved in 9. However, 9 hung at least twice during indexing such that a force-quit was needed. So technically 8.x wins here.
  6. Simulators - Slight improvement in launching with 9. Also, much better to be able to have multiple simulator windows running. Switching between simulator devices thus greatly improved in 9.
  7. Jump to symbol - 8.x wins hands-down. Accoring the the docs, 9's indexing scheme is suppose to give you very quick access. In virtually all cases I tried to use command-click to jump to the declaration, it either sat there for several seconds before opening the relevant code window. Or, never did anything and left up the little popup window on the screen. In fact, you could command-click again and again to bring up even more instances of the popup window; all ultimately did nothing.

Similar problem here. I'm getting constant rainbow wheels and pauses as I type, probably because it's trying to build automatically every time I edit something. If I could turn that off it might be fine.


Rob

I feel so upset I've updated. I am on a 2017 15-inch MacBook Pro and I feels like I am working on an 2006 machine. Painfully slow.

Same here. Freezes, hangs with rainbow wheels too often. 'Jump to definition' either takes more seconds or does nothing at all. Compiling slower than before upgrade. Starting apps in simulator much slower.


I have projects mixing Objective-C and Swift. Mostly only one project open.

MacBook Pro (late 2012) - i5 2.5GHz, 8GB RAM

Experiencing the exact behavior. Xcode 9 has become unusable. Did you find a solution?

The most frustrating is that somehow ObjC editor is incredibly slow. Every time I start typing there's a couple seconds lag (probably due to autocomplete starting up). ObjC being very fluid to code was the one only saving grace for it compared to development in Swift, not sure how they managed to break that. Swift seem okayish to me, at least I didn't notice any particular performance degradation. Running on a late 2015 MBP with a eGPU (really helps with faster storyboards loading).

A possible workaround: recreate your project from scratch and re-add all the files. This could be a pain I know, but maybe worth a shot.

I noticed that when I created a new project it was not behaving badly. I have a big project so I'm not done with this re-creation yet, but early results are encouraging. I was experiencing one crippling issue where Xcode would start rebuilding when I merely typed in a file - and that appears to be gone.

Same. Xcode 9 and storyboards are killing me. Lots of fan heat. Spinning rainbows. I'm not debugging other people's software anymore, so I don't have any workaround ideas. I'm expecting the company that created this software to make it work.