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Re: Estimates for syncprov sessionlog and checkpoint



Andreas wrote:
How could one estimate good values for syncprov's sessionlog and
checkpoint values?

The way I see it, sessionlog should be big enough to store all possible
entries that are going to be added between replication intervals, is
that more or less it?

No. Read the slapo-syncprov(5) manpage again. It clearly says "All write operations (except Adds) are recorded..." Adds don't need to be explicitly saved in the session log; the added entry's entryCSN already makes it obvious that the entry is new.


And what is inside the sessionlog, the operation plus the data I
presume?

Just the entryUUID, entryCSN, and the type of operation. The actual data resulting from the operation is of course present in the entry itself.
Finally, what about the checkpoint? The admin guide says the sessionlog
is stored in memory, so what does a checkpoint mean in this context?

The manpage is pretty explicit about that too. "After a write operation has succeeded, write the contextCSN to the underlying database..."


--
 -- Howard Chu
 Chief Architect, Symas Corp.  http://www.symas.com
 Director, Highland Sun        http://highlandsun.com/hyc
 OpenLDAP Core Team            http://www.openldap.org/project/