Hi, I'm a Ph.D from Hunan University of China. Recently, our group are tending to analysis concurrent hash tables using different synchronization mechanisms, urcu-based hashing is one of our targets. Today, we running an urcu-based hash table with only ten percent update operations. We found its CPU utilization is only 3% (while in a read-only workload, the CPU utilization is 50%). Is there any writer performance limits for urcu? Or why this happened in your eye? There is our platform information: Intel SandyBridge EP with 2 sockets, each sockets with 8 cores and 2 physical threads for each core. OS: Ubuntu 14.04 LTS. Experimental configuration: 16 threads, ten percent of update operations and 1 million initial elements in hash table. We are looking forward for your reply. Thanks! -- aimlab zwchen