Idea 2021.1 UE on CentOS 8 throws a UI was frozen error frequently



 I am using the Intellij IDEA 2021.1 Ultimate Edition on Cetn OS 8. I don't get any clikable icon like in Windows and hence i always to go the bin directory and run the '' file.

 I just noticed that it spits the following lines in the command prompt/terminal and need your help to resolve this.


2021-07-04 21:15:13,466 [  59430]   WARN - .diagnostic.PerformanceWatcher - UI was frozen for 7608ms, details saved to /home/raghs/.cache/JetBrains/IntelliJIdea2021.1/log/threadDumps-freeze-20210704-211510-IU-211.7628.21-7sec 
2021-07-04 21:15:31,967 [ 77931] WARN - .diagnostic.PerformanceWatcher - UI was frozen for 12950ms, details saved to /home/raghs/.cache/JetBrains/IntelliJIdea2021.1/log/threadDumps-freeze-20210704-211524-IU-211.7628.21-12sec
2021-07-04 21:15:51,330 [ 97294] WARN - ctionSystem.impl.ActionUpdater - 1704ms to expand group child
2021-07-04 21:15:51,330 [ 97294] WARN - ctionSystem.impl.ActionUpdater - 1765ms to expand group child space.actions.MainToolbarActionGroup
2021-07-04 21:15:52,822 [ 98786] WARN - .diagnostic.PerformanceWatcher - UI was frozen for 7251ms, details saved to /home/raghs/.cache/JetBrains/IntelliJIdea2021.1/log/threadDumps-freeze-20210704-211550-IU-211.7628.21-7sec
2021-07-04 21:16:12,901 [ 118865] WARN - .diagnostic.PerformanceWatcher - UI was frozen for 11540ms, details saved to /home/raghs/.cache/JetBrains/IntelliJIdea2021.1/log/threadDumps-freeze-20210704-211606-IU-211.7628.21-11sec
2021-07-04 21:16:24,346 [ 130310] WARN - ctionSystem.impl.ActionUpdater - 1003ms to expand group child ToolbarRunGroup
2021-07-04 21:16:28,269 [ 134233] WARN - .diagnostic.PerformanceWatcher - UI was frozen for 5217ms, details saved to /home/raghs/.cache/JetBrains/IntelliJIdea2021.1/log/threadDumps-freeze-20210704-211628-IU-211.7628.21-5sec
2021-07-04 21:17:26,813 [ 192777] WARN - .diagnostic.PerformanceWatcher - UI was frozen for 13115ms, details saved to /home/raghs/.cache/JetBrains/IntelliJIdea2021.1/log/threadDumps-freeze-20210704-211718-IU-211.7628.21-13sec

Question about CentOS desktop entry is answered at

As for the freezes, pleasse share the thread dumps (/home/raghs/.cache/JetBrains/IntelliJIdea2021.1/log/threadDumps-freeze* and idea.log file). You can use for that 


Thanks Konstantin Annikov. Let me upload the files with the JetBrains Team.


Don't forget to share the upload ID afterward. 


Hi Konstantin,

I have uploaded the latest entires for today, along with the idea.log file. They are available here :

Upload ID: 2021_07_05_59uzBorETaqRreKz


One other Q: Till whenI was running the Intellj IDEA in the terminal, I was able to make out the delay from the logs. Now based on the help you provided for my query in another thread - by making it a desktop shortcut, all I have is the clickable GUI icon on the screen and I dont get to see anythin behind the scenes. So I better always invoke it from the terminaL? Kindly advise. g


I do not see a common pattern in the provided threads. They are different and AWT thread (which is painting GUI) is working without delays. 

What is observed from the interface point of view? Do you notice a freeze? 


All the logs you saw in the command line are being recorded to idea.log:


Yes, I see a slowness in starting up.


What kind of slowness? 

According to thread dumps, the IDE is importing the project from Maven and indexing it. 

May you share your workstation info (CPU, RAM, disk type) and project info (how many lines of code, what filetypes and so on). 

As a general troubleshooting step, please disable all custom plugins: and reset settings to default via File | Manage IDE Settings | Restore Default Settings


sure. It was the initial hiccup it seemed. Thereafter I did not experience much issues. But during the startup I could clearly see the things happenings on the console and hence I came to the forum.

I use Lenovo Legion  Y540 with Windows 10, 1 TB HDD + 256 GB SSD, 16 GB RAM. I also use VMWare with CentOS 8 ,and that is where I get this slowness issue on the terminal. Not on Windows 10. Perhaps it is due to the VMWare thing the slowness is injected?


> Perhaps it is due to the VMWare thing the slowness is injected?

Most probably. The initial startup produces a lot of disk operations. And in case VM is located on HDD and access to the disk is proxied through VMWare, there is a possibility that the IDE will index the project slower than expected. 



okay. Yes, the VM is on the HDD but the primary OS (Windows 10) in on the SSD. Thank you.

I think I can leave this for a while now, until it becomes unmanageable.


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