Intellij idea 32 bit vs 64 bit speed and performance

Question

Currently I am using intellij idea 14.0.3(earlier I was using 12.1.4) on 64 bit windows 8.1.

When we install it, the installer creates the shortcut in start menu and other places which defaults to the 32 bit .exe file even on a 64 bit system.

I know that I can use the 64 bit executable to run idea in 64 bit mode as given in this SO answer.

But is there any significant performance difference between the two versions of the IDE?

And which executable is recommended for 64 bit systems? Shall I keep using 32 bit? or shall I switch to 64bit version?

Answer 1

The difference between running the 32 and 64 bits launcher is which Java will be used to start the IDE and what are the vmoptions parameters passed to it.

When starting the 32 bit one, IDEA uses it's own bundled 32 bit JRE. If there is no such one, IDEA tries to find 32 bit JRE in several places on specific order (%IDEA_HOME%, %JDK_HOME%, %JAVA_HOME%). The values in idea.exe.vmoptions are passed to it.

When starting the 64 bit one, it tries to find 64 bit JRE in several places on specific order. The values in idea64.exe.vmoptions are passed to it.

So if you want to allocate 2 GB RAM or more (with -xmx), this is not going to happen with 32 bit Java (resp. IDEA). And for large projects using less than 2GB causes the IDE to hang a lot. For smaller projects I don't think you'll feel any difference.

For reference this is the bug about this, so far they are not acting on it:

https://youtrack.jetbrains.com/issue/IDEA-146040