http://blogs.sun.com/jrose/entry/linkage_tables_in_the_vm (forthcoming)

Constant pools are inefficient for application linkage:
- they duplicate information shared between classes
- they mix mutable and immutable data
- their tagging scheme makes the VM vulnerable to race conditions

The solution is to remove constant pools as a primary structure in the Hotspot JVM, replacing them by linkage tables.

Features:
- separate mutable from immutable information (making the latter shareable)
- use memory coherence of single-word updates for safe state changes
- can be shared among groups of classes (directly read from Pack200-type inputs)