Nice! As far as I understand, it uses RCU-like epochs, except that the reclaimed memory is immediately used for the new version of the data, bounding the memory

Nice! As far as I understand, it uses RCU-like epochs, except that the reclaimed memory is immediately used for the new version of the data, bounding the memory usage at the cost of having the writer block. The oplog seems quite an additional complication, but I guess it makes sense for costly updates. The simplest solution is to just copy the last version over the stale version. edit: note this is not just a map datastructure. As far as I understand, left_right can wrap any data structure.