FYI here's a concurrent version of BLP (I haven't implemented it but I stole their simplified insert algorithm): https://pdfs.semanticscholar.org/6d6c/ca94c57d408c0b1164d6ff.... Also see a compact version (concurrent Cleary hash table) by the same authors: https://www.researchgate.net/profile/Alfons_Laarman/publicat....