How do i diagnose hotspot problems? Can i prevent some of my code from being JIT'ted?

Davanum Srinivas

If you see HotSpot errors you can work around other situations using the following procedure:

1. Add -XX:+PrintCompilation to your Java args.

2. You'll get a bunch of output lines like

337      java.util.StringTokenizer::scanToken (92 bytes)

3. When you get the HotSpot error, look at the previous line printed (if 
there's a lot of threading it's possible it could be  a few back)

4. Add a file .hotspot_compiler in the directory you run Java in 
containing the name of the method:

exclude java/util/StringTokenizer scanTemplate

(The delimiters *must* be tabs.)
You should now be able to run again without getting the HotSpot error.