[Issue 9692] Insertion rate in large groups slows unexpectedly

https://bugs.openldap.org/show_bug.cgi?id=9692

--- Comment #4 from Ondřej Kuzník ondra@mistotebe.net --- For posterity, the assumption was that adding a new value to a large multival enabled attribute would cost on the order of O(log n) where n is the number of existing values, however testing showed that the time it took to actually perform this was at O(n).

Further analysis showed that the cost was due to back-mdb (just like other backends) having to materialise the whole entry before modification to facilitate schema and ACL checking. The time to perform actual insertion was dwarfed by this as would be expected.