Estimates for syncprov sessionlog and checkpoint

[Andreas <ahasenack@terra.com.br>]

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?

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

Finally, what about the checkpoint? The admin guide says the sessionlog
is stored in memory, so what does a checkpoint mean in this context?