Hi, I have a database with about 1 million integer keys. Now I want to append a lot of small values (each 3 bytes) to random keys very often (tens of millions of times). How do I insert into the database the fastest? Currently I am trying the following setup, but I wonder if that is optimal, because I see a decrease in indexing speed after about 500000 random writes (here appends): - I have split the whole key range into 16 databases (each within a different lmdb environment), so each range-db holds about 65000 keys - I open each range-db with the flags: MDB_APPENDDUP | MDB_INTEGERKEY | MDB_INTEGERDUP | MDB_DUPSORT - then when I want to append 3 bytes to the value of a key, I use the following call: res = mdb_put( txn[dbnumber], db[dbnumber], &k, &v, MDB_APPENDDUP ); Thank you for your help! -Tom