Berkeley DB needs too many write locks on specific size of the records

Hi,
I put records to the Berkeley db row by row in single transaction. And i have discovered significant increase of write locks on some specific size of the data.
For example when i put 1000 records, where each record data size is around 3500 bytes, transaction uses 428 locks. On bigger or smaller data size transaction needs fewer locks.
I put statistic in the table:
Record size Lock number needed by transaction
~1400 169
~3500 428
~4300 6
I think it is somehow related to the page size(16384) or cache size (64Mb)
Could someone explain why transaction needs so many write locks with data size ~3500 and fewer locks with data size ~4300?
Is there any way to avoid that raise of lock number? If not, I need to measure maximum number of locks needed for successful end of transactions. Understanding of the source of that issue would help me to prepare data which require the biggest number of locks for putting it in the database in one transaction.
Thanks in advance.

Please delete this post and repost in the appropriate forum. Thank you.

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Message was edited by:
user647892

There is nothing wrong.
Oracle by default locks records. In case 1, you insert a record (1 row level lock) and update that same record. Why is a mystery, but the update doesn't require a lock (by you) as you already did lock the record.
In case 2, you have distinct keys for each line, so each line results in a row level lock as expected.
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