If they knew what they were talking about they wouldn't have used a raw filesystem benchmarking tool to prove their arguments. They would have used a pair of ac

If they knew what they were talking about they wouldn't have used a raw filesystem benchmarking tool to prove their arguments. They would have used a pair of actual, comparable DBMS implementations. Single-writer is all you need if each write is fast enough. BerkeleyDB, which we used before writing LMDB, is multi-writer. It's still slower than LMDB in every workload, because of all of the lock management that comes with being multi-writer.