Bad JetBrains Intellij IDEA and Android Studios CPU usage on Ubuntu

Question

As an Android developer I've been moving away from Eclipse to Intellij IDEA for production code in anticipation of Google's Android studios which shares a code base with IDEA.

My experience has been a good one up to this point. I've only been using IDEA at the office, where I have a 4x core Intel i7 machine running Ubuntu 12.04 LTS (Sun JDK/JRE), up to this point and I've never noticed what the performance of IDEA really is.

Now however after setting IDEA up on my personal computer at home the performance is abysmal. Memory usage is normal, but the constant CPU usage bounces between 80%-100% (over the whole application lifecycle). And that is when nothing else is running on the machine and no work is being done, by me or visually by the IDE.

This makes IDEA unusable when working on it, and I can forget about having anything else running along side it.

My home specs and software are:

• Intel Core 2 duo 3GHz
• 8 GB RAM
• Ubuntu 12.04 x64 LTS (3.8.0-35-generic) running of SSD SATA
• Intellij IDEA 13.0-0ubuntu1 build: IC-133.193
• Tried both OpenJDK and Sun

And the strange thing is that this happens as well with Android Studios.

All help in trying to debug this behaviour would be appreciated.

#Edit 1:

Noticed that the CPU load falls down to 20% when bringing up dialogs (Project structure, Settings, etc) and then goes right back up when dismissing them.

#Edit 2:

I tested simply getting the tarball straight from JetBrains, instead of using the one in Canonical's ppa. The performance was significantly better for at least an hour (20-30% CPU usage while idle). Seems that the native file watcher in C-PPA wasn't working properly and was indexing the whole filesystem. However the performance became worse after the first hour or so, going back to 90-100% CPU.

Answer 1

The issue turned out to be the native-file watcher being out-of-date. IntelliJ was re indexing my whole drive it seems. Was fixed by uninstalling the version gotten from Canonical's ppa and installing directly from JetBrain's own webpage.

Answer 2

Are you using any plugins outside of the included ones which might cause issues.

I don't run Ubuntu anymore but can't recall any issues with high CPU-usage when i did. (I use Fedora with KDE a colleague uses Fedora with GNOME though. ) Does this always happen or only when you have a project open? I'm thinking if this might have something to do with the background-compile that IDEA does. Might be worth trying to turn this off.

Found under Project Settings -> Compiler -> Make Project Automatically

worst case it is a Unity-integration issue or something. Haven't used unity so can't say.

Answer 3

Usualy I manage to fix it by deleting IDE's index files rm -rf ~/.RubyMine60/system, don't forget to change .RubyMine60 to IDEA's config folder

Answer 4

If you're willing to do some sleuthing, you could run the Oracle JVM and use the VisualVM profiler to see where the IDE is spending all its time, presuming it's a Java-based process that's actually eating your CPU cycles.