RCU Judy Array (optimisation over Radix Tree)

Hi Matthew,

Following our discussion at LinuxCon about Radix Trees and Judy Array, here is a pointer to my user-space implementation prototype of RCU Judy Array. I've simplified it a bit (removing features you don't need, just keeping fixed-sized integer keys), and it can still be simplified quite a bit by removing partitioned locking support, but it may contain nice ideas for radix tree improvements regarding the number of cache-lines touched by radix tree lookups.

It's available in this branch:

https://github.com/urcu/userspace-rcu/tree/urcu/rcuja-simple-int

Here are Linux Plumbers 2012 slides and video from a few years ago:

http://www.efficios.com/lpc2012-scaling-rcu-judy-arrays-cache-efficient-compact-fast-and-scalable-trie

Feedback is welcome!

Thanks,

Mathieu

Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com