Berkeley DB Family

Hi guys!

I need to compare the btree and recno format in bdb.
i have some binary dbs with short fixed size records, i can get the records from them in recno format faster than in btree format .the number of records in these dbs is like 1000000 or 2000000 .

and i have some other binary dbs with long(average 620 Kbyte) and variable record size, and i can get these records faster in btree format.the number of records in these dbs is like 1000 or 1200 .

can anybody help me to find or explain the reason, why is getting big and variable records slower in recno format than btree and why is recno faster for short and fixed size records than btree ?

I can' t find the data base structure of recno format in BDB.


thanks and regards
soudi