Fusion apps spend ~10% of their time in string intern because they have such a large number of interned strings; the table gets too full and searching it becomes a huge bottleneck.
We have experimented with changing the size of the string table, and a larger table increases our performance by 7-10%.
We are aware of the new property in JDK 7 for changing the size of the string table, but fusion apps will not be able to move to that release for quite some time. So in a sense, this is a request for a backport of 6962930 -- however, that bug is also tied into moving the string table into the heap (out of permgen). We don't need all of that -- if we can set the size of the string table within permgen at startup, that will be sufficient until we can move to JDK 7.
[Not sure about the subcategory here, but 6962930 is in this subcategory...]