Performance and memory problems when using CLion

Assuming you have a fairly large code base in modern C++, or rely heavily on templates or macros usage, performance and memory issues during indexing and editing are possible in CLion. While we constantly work on improving CLion performance and memory usage, we recommend you check these Performance tuning tips in our web help:

To report a performance problem, please follow these instructions. To find IDE logs to attach to the problem, use this link.


26 out of 130 found this helpful

Having very similar issue with IDEA.

os: macOS mojave

cpu: 8th gen i7

mem: 16gb @ 2400mhz

Intellij IDEA @ 2018.3.1

No matter how much memory I've allocated to IDEA, it tries to consume it all and the editor gets really slow and non-responsive. I've allotted 1 -> 1.5 -> 2 -> 2.5 gb of ram and it still eats it all up. Doesn't matter what its set to.

This is a serious issue and extremely bothersome. May be going back to vscode if this doesn't get resolved.


Are there any other actionable items for performance issues? I have more than sufficient memory available sitting unused, yet something as simple as toggling between header and cpp file takes 10+ seconds. CLion performance seems to have steadily degraded over the past year I've been using it to the point that it's bordering on unusable for me now.


My CLion (2018.3.4) goes crazy with memory usage. It starts normal but sometimes at reloading my CMake it hangs some minutes and than shows the "Out of Memory" window. I already allowed -Xmx 20'000 MB but it still happens. This cannot be normal right?




Webstorm is using all my RAM (16GB). It is freezing my ubuntu 18.04 with no option more than power off the computer.


I am having the same problem.  I set the heap to 2g so that I can get more time before the memory is used up.  

I may not continue my subscription and just switch to vscode.   This problem has been around for a long time and has never been resolved. 

FYI - I get this with a clean setup developing angular projects. 


I use WebStorm on two MacOS - MacBook Pro 32gb ram and MacMini 16gb ram. No matter how much heap I set WebStorm use it all. When I set 4gb sometimes it need 2 days, sometimes if I have multiple instance of WebStorm it use it during 4-6 hours. It's not enough to close WebStorm instance - I must close all instances, kill app and start it again to get memory free.

It's really annoying.


Intelij IDEA Stable version 2019.2 currently is using 6 GB of RAM after 1hour. Developers in our team are getting annoyed that they must restart IDE a few times per day. Setup macOS Catalina and High Sierra, Java8, default properties. 


We have 6 professional licenses in out team, could you help us? 


I am also having the same issues on Webstorm, Phpstorm and IDEA, no matter how much I increase the memory heap it eventually reaches the limit. I'm having this for months now and I have to restart the IDEs on regular intervals to keep working, these have to be memory leaks.


Ubuntu 19.04
Rubymine 2019.2.2
Java 11.0.3 (the one that Toolbox gave I guess)
htop command to analyse my memory usage

For me, it seems that it has nothing to do with heap memory size (because it stays the same overtime). It seems to be the IDE itself. I only need to open Rubymine and let it go for a while (few hours) and it can jump from 620M to 1300M without doing anything. I even tried to stop the debug instance but it did nothing. What's weird is that stopping the debug instance is not releasing the small memory it took. 

But what I found by doing this is that stop/starting a new debug instance or restarting it also increases my laptop memory usage each time, without freeing the previous one, though it has nothing to do with the fact that it increases memory usage without doing anything.

Probably because I let my Rubymine with a debug instance opened? I should investigate more.


I've just upgraded phpstorm from 2018.2.1 to 2019.1 and memory issues started immediately. increased Xmx to 2GB, Activity monitor shows 2.53GB in use, and still feels slowish at times. 





Its incredible, but the CSV plugin was taking all my 32GB of RAM. Disabling it fixed it.


Same with Intellij (no surprise) - I have Xmx to 7750m and using IDE for ~4 hours ends with about 4.5 GB unreleasable memory....


I had this problem after upgrading to 2020.1.1, and disabling git and other VCS plugins did not work for me. What did work was disabling CSV Plugin, as suggested in this other issue:


Seeing as I just renewed my JetBrains subscription and this is still happening across all or nearly all products, it's very disappointing.  Just had Rider puke after consuming 11gb of memory on Mac.  Granted it's for a 100 project sized solution, but the memory consumed is kind of ridiculous given the entire code base.  

I run Node, Angular dev server, MongoDB and Apache Livy outside of IntelliJ Ultimate in Iterm sessions.   
The only thing running in Intellij is the editor and sometimes the debugger.   The memory shows around 250mb when I first start and after about an hour or 2 it increases close to the 2G max that I have set.   This has been happening for about a year and I have tried every version of Intellij with the same problem.
Is this a bug with the typescript support ?   -  When I switch to my Scala / Spark projects I don’t have this problem. 
Not sure how to take a memory snapshot but will search on how to. - John

Similar issue for me. CLion EAP 2019.3 is using 11GB of RAM and I get a message that memory is getting low and I should consider increasing the heap size. Very frustrating.

By the way, I am on  Mac OS X and the clion.vmoptions has  "-Xmx2000m". Yet the heap memory limit reported in the bottom right corner is over 9GB! Very often it will show it being fully used.



Dear Jetbrains folks, I am encountering this issue among several others in the new 2020 builds (used 2020.1 and 2020.2).

Last day I had to delete all of my .idea folders to prevent the IDE from crashing on start right away.

This is unacceptable. Fix you 2020 releases! I am a professional getting paid to program not beta testing your latest features. I will eject myself from your ecosystem if you can't deliver a stable product in the future. I'd rather use VSCode than dealing with crashing IDEA's half of the time.


Sincerely, one of your IntelliJ ultimate users


Do we have any solution for this performance issue? I am using Pycharm inside my virtual box and its eating all my memory and slows down my performance. How can I fix this performance issue. Please suggest.


** Work Around **

I've been investigating this issue for a few hours with Visual VM.

I was seeing a tremendous spike and obvious memory leak with Java 11 version that Jetbrains is using. The graph above is showing garbage collections but every increasing memory usage.

The Specs are this

PID: 66319
Host: localhost
Main class: <unknown>
Arguments: <none>

JVM: OpenJDK 64-Bit Server VM (11.0.6+8-b765.40, mixed mode)
Java: version 11.0.6, vendor JetBrains s.r.o
Java Home: /Users/xxxx/Library/Application Support/JetBrains/Toolbox/apps/CLion/ch-0/201.7223.86/
JVM Flags: <none>

It boils down$Source#17

I disabled all the Version control systems plugins and the spike went away and the memory now bounces around 150MB like it's suppose to.

It seems to have to do with this:



Its the CSV plug in for me don't install that plug in!!!!!


I have the same issues on PhpStorm for a few days now. Can't continue working like this.


Had the same problem. Disabling the CSV plugin solved this.


I did the same but it’s only give me more time between restarts...


For me, the memory increases when I place the cursor on a line that contains a suggestion, like class import and then I use the keyboard key combo to resolve the error "import class". Immediately, the heap spikes and the app runs out of memory.


Hi, I am facing the same issue of low memory after using webstorm fro 1-2 hrs and after that its kind of impossible to keep using webstorm. Is there any timeline when will this issue be fixed?


After some time clangd uses about 300M and max heap size: 7,9G, allocated 7.8G, used 7.8G. OS X 10.14.5, Clion 2019.1.4.


Same issue with phpstorm - constantly using more memory until it becomes too slow I have to restart the IDE. It constantly endup using swap when I have more than enough RAM available. 

That's a serious issue for productivity and I'm seriously considering joining those switching to another IDE even after several years using phpstorm loyally 


FWIW - I am see the same issue in Rubymine and Webstorm almost daily.  The longer I use the IDE the more memory it consumes until it becomes painfully slow and I have to restart. The larger the codebase the faster it happens.


Same memory issue with phpstorm 2020.1.1.  Only temporary solution I found is to downgrade to 2019.3.


Having the same problem, latest PhpStorm increases RAM consumption constantly until eventually nothing is left, Ubuntu 18.04 does not respond so I have to power off


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