&gt; LMDB writes will keep data exactly where it was placed the first time it was written.<p>Wait a minute. I was under the impression that the reason LMDB works so well under concurrent access is that it _never_ modifies anything in place, but when it has to modify a value it will copy the existing content of the page along with the new value to some unused place... so data _is_ moved between updates.<p>Or am I missing something ?