GC Tuning - preventing a Full GC

Question

I\'m trying to avoid the Full GC (from gc.log sample below) running a Grails application in Tomcat in production. Any suggestions on how to better configure the GC?

Answer 1

Your survivor sizes aren't decreasing much, if at all - ideally they should be decreasing steeply, because you only want a minority of objects to survive long enough to reach the Old generation.

This suggests that many objects are living a relatively long time - which can happen when you have many open connections, threads etc that are not handled quickly, for example.

(Do you have any options to change the application, incidentally, or can you only modify the GC settings? There might also be Tomcat settings that would have an effect...)