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Re: syncrepl ramblings again

Kurt D. Zeilenga wrote:

What was the motivation for not keeping tombstones around?

Tombstones, in general, don't hold enough information for
the provider to determine whether or not a delete message
has been sent to a prticular client, resulting in need to
send extra deletes messages. Sessionlogs, on the other
hand, track exactly which deletes a client needs to see.

Note that the question the provider has to answer is
subtlely different than "what entries were deleted since
the client last sync'ed?" but "what delete messages does
the client need in order to sync?". Sessionlogs are better
at answering that question.

I'm not disputing the value of the sessionlog. But if a tombstone carries entryDN, entryUUID, and entryCSN, then it would seem pretty unambiguous to me. The client just says "send me everything >= my-last-CSN" and everything should be fine. No?

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