I find intellij IDEA to be slow. It can take quite a while for it to synchronize if I edit files using anything besides IDEA. Sometimes while it's trying to look for errors in my code, or garbage collect, or whatever it's trying to do, I can't do anything else. Maybe I have my project setup poorly. I don't want to turn off the little green/red light in the corner, and I find most of the features in IDEA beneficial, but is there any work being done to make IDEA faster and more efficient? I see the notes about work being done for 4.5 and all I see is lists of features. I'm pretty happy with the features at this point, I just want it to run more smoothly and efficiently. I want it to never hang.
Once in a while someone will come to my desk and want to look at a file, and while IDEA thinks, I have to open the file with vim, edit it, and check in the file. When I finish sometimes IDEA is still just thinking. Sometimes for the features it's worth it, but other times I just feel silly. I am using a P4 w/ a half a gig of ram running a recent version of rehat linux. It's not the computer that is at fault, although it may be the user; maybe I have something setup funny, I don't know. I'm using it for a fairly large project, over 1500 classes. Is the size of the project an issue? I've never used IDEA on smaller projects. I would expect that the IDE is written to handle large projects though; why else would someone bother using an IDE?
Either way, I'd love to see more emphasis put on performance rather than features. I think that's the bigest thing IDEA has going for it. The reason I started using IDEA was that I heard it performed better than other IDEs and I couldn't see the point of using an IDE if it was going to be slow. If they continue to add features without focusing on performance it's just going to become another POS IDE.