[concurrency-interest] A Fast Wait-Free HashTable

Joseph Seigh jseigh_cp00 at xemaps.com
Wed Feb 21 20:56:44 EST 2007

David J. Biesack wrote:

>Does anyone know more about Cliff Click's wait-free hashtable?
>"A Faster Wait-Free Hash Table"
>"I present a wait-free (lock-free) concurrent Hash Table implementation with better single-thread performance than most Hash Tables, and better (usual much better) multi-thread performance than all other implementations I tried. I demonstrate scaling up to 768 CPUs even with high mutation rates. I show correctness by looking at the problem in a very different light than the usual "happens-before" / memory-order / fencing style of thinking -- indeed the algorithm requires no memory-ordering, no memory fencing, no D-CAS and no CAS-spin-loops."
>Sounds interesting. Has anyone seen or reviewed the design or implementation, or comparisons to ConcurrentHashMap?

No.  I guess we'll have to wait for the wait-free hash table. :)

I sort of have a blocking linked list which runs about 3X faster than 
under high contention on a single processor system.  I am waiting for a 
768 processor
system to test how well it will really scale.

Joe Seigh

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