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Re: openldap 2.3 recommended bdb version

Aaron Richton wrote:
> OpenLDAP 2.3 requires that you use the transactions patch to BDB
> 4.2.52

 Strictly speaking, this isn't true. It's greatly beneficial to run
 with Degree 2 isolation, but if sites believe they have a compelling
 reason to not use unofficial patches, they don't have to. It's
 probably not in their best interest, but who are we to judge? (Until
 they start asking openldap-software why their disks fill...)

 I have a feeling that the Degree 2 isolation patch is going to become
 a FAQ as 2.3 gets adopted. I've tried to summarize under "Which
 version of BerkeleyDB should I use?" in the FAQ-O-Matic; revisions
 encouraged. Hopefully this will eventually get to be a Google hit for
 "BerkeleyDB 4.2.52 library needs TXN patch!"

Thanks for writing that. I've made some updates. Not completely happy with the focus on "Degree 2 isolation," as that's actually an independent issue. Really the point is that BDB 4.2 has a bug in its transaction initialization sequence that is fixed in 4.3, and the patch we provide for 4.2 is a hack to bypass the bug in one specific use case. The patch is by no means a general-purpose fix, and it does not provide Degree 2 isolation for BDB 4.2, and OpenLDAP does not invoke BDB 4.3's Degree 2 isolation support. I'm not sure the details are important enough to spell out in the FAQ, but still thinking about it.

 -- Howard Chu
 Chief Architect, Symas Corp.       Director, Highland Sun
 http://www.symas.com               http://highlandsun.com/hyc
 Symas: Premier OpenSource Development and Support