Intellij only using 750m, configured to use a lot more

Question

I've modified the Intellij Custom VM options to this:

# custom IntelliJ IDEA VM options

-Xms16g
-Xmx17g
-XX:ReservedCodeCacheSize=4g
-XX:+UseConcMarkSweepGC
-XX:SoftRefLRUPolicyMSPerMB=50
-ea
-Dsun.io.useCanonCaches=false
-Djava.net.preferIPv4Stack=true
-XX:+HeapDumpOnOutOfMemoryError
-XX:-OmitStackTraceInFastThrow
-Dawt.useSystemAAFontSettings=lcd
-Dsun.java2d.renderer=sun.java2d.marlin.MarlinRenderingEngine

If I'm not mistaken, that means it should be using about 16~17g, with 4g reserved.

However, I enabled the memory monitor in the status bar at the bottom, and it only shows 750M available (which it is regularly using up).

I'm running 64-bit Ubuntu with a 64-bit JRE and JVM. Running Intellij IDEA Ultimate 2017.3.1. My machine has 64G of memory.

I've restarted since making the VM option changes. Am I missing something?

Answer 1

Check the desktop entry for IDE (should be located in ~/.local/share/applications/jetbrains-idea.desktop or in /usr/share/applications/jetbrains-idea*.desktop). Could be that the option is overriden in desktop entry.

Answer 2

I've found a partial answer.

If I run bin/idea.sh directly from the command-line, it will pick up my changes. If I lock that to my taskbar and re-run it from there, it does not. I'm guessing it has to do with which user it is looking for or something (since the file is in my home directory).

There is another idea64.vmoptions in the bin directory with idea.sh. If I modify that, then my changes will get picked up even when I run it from the taskbar. I'm using that for now and it works.