UI freezes in JetBrains IDEs aren’t always caused by heavy work on the event dispatch thread — our recent investigations reveal a frequent hidden culprit in plugins: long, non-cancellable read actions running in background threads. In this post, we break down why APIs like ReadAction.compute and run…

First :slight_smile: Plugin BashSupport Pro, ID 13841, https://plugins.jetbrains.com/plugin/13841 (Not open source) For example, a user reported that he uninstalled because it supposedly freezing the IDE. I couldn’t ask for more data because it was posted anonymously. Thanks a lot!

Second :slight_smile: Plugin Cursive, https://plugins.jetbrains.com/plugin/8090-cursive (also not open source). I’ve seen various cases where the IDE has complained about Cursive slowing things down. I’ve fixed the ones I have traces for, but if you’ve seen any more I’d appreciate any advice. I ha…

flutterX: https://plugins.jetbrains.com/plugin/18986-flutterx (Open source) It uses a large number of readAction and runReadAction

Plugin: RyeCharm Source code: GitHub repository I don’t think I have received any freeze reports yet, but it would be useful to know if I have been writing good code.

Why can’t plugin authors get these in stack exceptions? Because figuring out where the stack trace actually came from isn’t possible? It sounds frustrating that Jetbrains has enforced coroutines and other changes without proper error reporting?

[image] ANSI Highlighter Premium - IntelliJ IDEs Plugin | Marketplace 5 USD per year - Try it before you buy it ANSI Highlighter Premium enables the fast rendering of ANSI control-code sequences in log files, regardless their size, from... Curious to know if …

First of all, I would like to thank Joachim for the fantastic blog on error reporting How to implement error reporting in an IntelliJ plugin How to implement error reporting in your IntelliJ plugin. Since BashSupport Pro uses com.intellij.errorHandler we se…

Colin if you don’t mind here are a couple of freezes related to Cursive, and we will send you full reports and dumps privately. Non-cancellable read action in a background thread Here is an excerpt from thread dumps. Look for com.intellij.openapi.application.impl.ApplicationImpl.runReadAction call.…

[image] Joshua Taylor: Why can’t plugin authors get these in stack exceptions? They definitely can! We receive only fraction of reports when a cause of a freeze is unclear. To improve your error reporting please do not forget to implement a errorHandler. How to implement error repo…

For FlutterX I have not managed to find any freezes in our reporting, most likely because the audience of the plugin is mostly Android Studio users. We do not control the error reporting in Android Studio, issue reports there go to Google Inc.

Blog post: UI Freezes and the Dangers of Non-Cancellable Read Actions in Background Threads

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Blog post: UI Freezes and the Dangers of Non-Cancellable Read Actions in Background Threads

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