[Issue 10220] Feature Request: new option for append-only write transaction

https://bugs.openldap.org/show_bug.cgi?id=10220

--- Comment #2 from Xianghao Tang xhtang518@gmail.com --- (In reply to Howard Chu from comment #1)

No, nor is it necessary. If you want to make LMDB ignore the freelist, just keep a read transaction open all the time.

An active read transaction can prevent pages already in DB from being reused, but futher write commits will create new tree node pages, then I need to reopen the read transaction every time, which sounds a little weird.

Besides, append-only write is friendly to MDB_NOLOCK in single writer scenario, but this workaround requires the writer to check lock.mdb, resulting in extra I/O cost.