Performance of new compiler system

Idea is now propagating the new compiler system so I gave it a trial.  I was surprised that the compilation takes now much longer than before with fsc.  While fsc displayed the first compiler errors after 1-2 seconds the new compiler system takes around 3-4 seconds for that.  Is this something we have to live with?  I already searched for "fast scala compiler" in the settings but could not find it anymore.  Is fast compilation no longer supported?


FSC is still supported. But turning it ON is not obvious.
1. Go to 'Global' Settings -> Compiler -> and turn OFF external build
2. Now go to 'Project' Settings and make sure FSC is selected in all your Scala Facets.



That's exactly the setting I had before when IDEA told me this old compiler system is deprecated and will be removed soon.  That's why I tried the new compiler, but I switched back to the old one when I discovered that the new one is slower.  Let's see how long the old one will be supported.


I think internal compiler (including FSC) will be removed in IDEA 13 (it's not Scala plugin part, so I'm not really sure).

We are planning to support auto-make (but only in case, when application is not under debug), so probably it will be faster for you.

Best regards,
Alexander Podkhalyuzin.


That's a pitty. I doubt auto-compile will help me unless it uses another compiler interface that avoids the initialization overhead the new compiler system currently seems to have. I mean that's why we use fsc in IDEA, because it immediately compiles the changes.

Now I found another thread about configuring the new compiler.  I posted my experiences to


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