>whenever I see mmap associated with huge perf I tend to wonder about corruption
If that was the case with lmdb implementation, that works as OpenLDAP backend all over the world, most probably you would have heard about it from the news.
You've have a point. But then, it's a bench mark and it would not be the first time that a bench is done using different settings than in production. Like I said, that lmdb is used in OpenLDAP doesn't automatically mean it is used with the exact same configuration as in the benchmark ;-) Nor did I say a memory store is bad, it's just you're not comparing the same things. Redis could be added to the bench for instance.
If that was the case with lmdb implementation, that works as OpenLDAP backend all over the world, most probably you would have heard about it from the news.