We never targeted weakly-ordered architectures like ARM, only x86. We never used a wide variety of different processors. We are not developing the Linux kernel and are not into control dependencies, just relying on the fences and the memory model. There may be some CPU-dependent performance differences, like discrepancy because of NUMA or false sharing being noticeable on one processor, but not on another. RCU and hazard pointers are nothing new. For the disjoint sets we don't need them. For the forest patches and the tries we do. We are using TBB and OpenMP whenever possible and trying to keep things simple.