Why is string.intern() so slow?

Question

Before anyone questions the fact of using string.intern() at all, let me say that I need it in my particular application for memory and performance reasons.

Answer 1

This article discusses the implementation of String.intern(). In Java 6 and 7, the implementation used a fixed size (1009) hashtable so as the number entries grew, the performance became O(n). The fixed size can be changed using -XX:StringTableSize=N. Apparently, in Java8 the default size is larger but issue remains.