hanging eclipse problems - eclipse

Question

I'm having some weird problems with Eclipse lately. I haven't installed any new plugins that I think could have caused them (xcarecrows and m2eclipse, both already removed).
The problem is that Eclipse sometimes hangs on random things. Sometimes simply by opening it, sometimes clicking anywhere on the GUI while it's loading something, sometimes while pasting code (Java). But the biggest problem is that it doesn't unfrezze.
AFAIK the problem started when I experimented with settings in eclipse.ini, but I can't be sure because it was some time ago and it hasn't happened all that often.
I don't know how to find out what could be causing this so I'm asking here, maybe someone can suggest some diagnostics.
Also, here's my eclipse.ini, maybe there's something wrong in it:
-showlocation
-showsplash
org.eclipse.platform
--launcher.defaultAction
openFile
-vm
C:/Program Files/Java/jdk1.6.0_22/jre/bin/server/jvm.dll
-vmargs
-Dosgi.requiredJavaVersion=1.6
-Xms128m
-Xmx384m
-Xss4m
-XX:PermSize=128m
-XX:MaxPermSize=384m
-XX:CompileThreshold=5
-XX:MaxGCPauseMillis=10
-XX:MaxHeapFreeRatio=70
-XX:+CMSIncrementalPacing
-XX:+UnlockExperimentalVMOptions
-XX:+UseG1GC
-XX:+UseFastAccessorMethods

Answer 1

The canonical reference for this kind of issues is How to report a deadlock in Eclipse.
You will need to aquire the thread dumps of all threads. Perhaps it will give you insight of a bad plugin, or perhaps Eclipse itself.
If you suspect this is memory-related, you should read Getting a heap dump and analyse the resulting file in the Eclipse Memory Analyzer