Intellij IDEA is laggy

i have 2 HDD my C drive is 1 HDD and my E drive is another HDD

Aryiaxd

Could you manually replace the contents of your custom .vmoptions file (the one at the AppData location) with the following:

-Xms128m
-Xmx2048m
-XX:ReservedCodeCacheSize=512m
-XX:+IgnoreUnrecognizedVMOptions
-XX:+UseG1GC
-XX:SoftRefLRUPolicyMSPerMB=50
-XX:CICompilerCount=2
-XX:+HeapDumpOnOutOfMemoryError
-XX:-OmitStackTraceInFastThrow
-ea
-Dsun.io.useCanonCaches=false
-Djdk.http.auth.tunneling.disabledSchemes=""
-Djdk.attach.allowAttachSelf=true
-Djdk.module.illegalAccess.silent=true
-Dkotlinx.coroutines.debug=off

Then start the IDE and check if performance got better?

My CPU usage is still high.

What's the physical memory (RAM) size of your system?

I have a 4GB RAM

Your machine hardware is too old to run IntelliJ IDEA with acceptable performance. The slowness is caused by the old CPU and the lack of RAM. It causes heavy swapping on the slow HDD drive which makes the problem even worse.

Installing 16GB of RAM and SSD could help, but the whole system upgrade would be needed to get better performance with the IDE.

oh ok

about: "your machine hardware is too old to run IntelliJ IDEA with acceptable performance"

I was looking for this comment. Sorry, the whole discussion looks more like looking for something we can blame it on.

So I have the same issue, running on linux without any antivirus scanning ideas directory, on ssd, with 12 cpu system and 32G. Intellij got, for very small project 6G of ram to play with and if I click just on swing menuitem in top menu bar, sometimes I wait for 3 seconds for intellij idea to render it. Up-to-date idea, installed via jetbrains toolbox. The previous version without toolbox was snappy.

martin mucha Your issue is different, please report at https://youtrack.jetbrains.com/newIssue?project=IDEA with the CPU snapshot and the logs attached.

Intellij idea manually downloaded and ran with 700M runs MUCH faster than toolbox idea with 6G ram. And without any issues. So this is the solution for me.

martin mucha Toolbox version is exactly the same, so the issue is not clear. Please provide CPU snapshots/logs from both versions so that we can compare them and identify the problem.

sorry, if I didn't experienced any issue for several hours, I just got rid of toolbox installation. Which was 2 weeks old, and having same plugins. Anyways, even on 4G system you can have lightweight wm and 750M reserved for idea and it could run just well. So that answer might not be correct at all. 
Regarding toolbox. On this machine I installed toolbox into fresh installation. On another machine I moved from regular installation, which worked well, to toolbox version and it was laggy as well. Also more ram than chrome, fast ssd ... So while regular and toolbox are the same, they are not really. And we cannot blame it on wm either, it's the same both on cinnamon and kde. Sorry I cannot help you more.

> Anyways, even on 4G system you can have lightweight wm and 750M reserved for idea and it could run just well. So that answer might not be correct at all. 

It depends a lot on the size and type of projects you are working on. Try building IntelliJ IDEA Community project on a 4GB system and on a 32GB system to see the difference.

I updated the intellj to newest version, now i cant even edit anything it instant causes a 45-60 seconds freeze…

Hello,

Please try to disable custom plugins if any ("Settings | Plugins - cog wheel - Disable all downloaded plugins").

Do you face the issue with all file types? Could you please provide logs folder zipped (https://intellij-support.jetbrains.com/hc/en-us/articles/207241085-Locating-IDE-log-files) after reproducing the issue for investigation?

You may share large files via https://uploads.jetbrains.com/ form. Don't forget to provide Uploads ID