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Re: Long slapd shutdown times

Audrius Valunas wrote:

slapd shutdown may take hours to complete. the backend in use is BDB with berkley db version 4.2.52. The reason seems to bee flushing of transactions logs or similar. db_archive while slapd running says that ALL logs are still needed. And if wait for slapd to shutdown db_archive allows removal of all of them but last.

Is this behaviour feature, bug or some misconfiguration of mine ?

You didn't mention which version of OpenLDAP you're using, but probably all of the above:

misconfiguration: see the checkpoint directive in slapd-bdb(5).

feature: back-bdb uses a long-lived transaction for read operations, to avoid a cache deadlock issue. All the details are in this email thread.

bug: BerkeleyDB 4.2 holds the transaction log open even if a transaction hasn't done any writes. The long-lived read transactions that back-bdb uses causes the db_archive behavior you're seeing. This bug is fixed in BerkeleyDB 4.3, but as Quanah is quick to point out, BerkeleyDB 4.3 has other problems. I posted a workaround here:

This question was also discussed on this mailing list a couple months ago

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