IntelliJ 12 compiler speed

Reading about the new compiler I was looking forward to see faster compilations of my big project with IntelliJ 12. The project has almost 10000 Java-files, and it is set up to compile with the Eclipse-compiler, and the project structure is set up for Java 1.6. Am I supposed to get faster compilation with v12 over v11 then? You see, the point is that I don't actually get any noticeable compiler speed improvement. With v12 I get it all compiled at about one minute and 45 seconds, and with v11 the same project is re-built at one minute and 50 seconds. Are there some requirements to use the new compiler? Must I compile for Java 8 or Java 7 in order to be able to use the new compiler? Do I have to compile with the "javac" compiler and not Eclipse?

Anyway, the new Darcula theme looks great. My colleagues are finally starting to ask questions about my IDE over their own Eclipse... ;-)

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Hi Leif Erik,

There are no special requirements for using the new build system.
The spead of compilation depende on your project, operating system, type of file system, disk hardware etc.
For example, the new build system launches javac(or eclipse) compiler in-process. It could be so that compiler requires lots of memory for its internal structures and the whole build process experiences frequent GCs. Please try to increase heap size for the build process and see if it makes any difference.
Another point is that we've done a number optimizations in the way javac interacts with file system and avoided some expencive IO calls. So switching to javac compiler may also change the speed of compilation

Also in the nearest updates we are going to provide "self-profiling" functionality for the build process, so you'll be able to record CPU snapshots of your builds and send them to us for analysys.

Best regards,


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