Actually, its not a "full" reload, but a update+present refresh
that will be common event. They occurs only during refresh and
then only when something has changed. So, avoid refresh (use
persist mode) and keep the retry interval short (to reduce the
chance something changes while disconnected).
As Jong noted, history information is needed to use the
updates+delete mode (except when there are no deletes, context
CSNs can detect that). That should make syncrepl good enough
for *most* directory deployments. Syncrepl, even with optimal
selection of transfer mode, is likely not good enough for larger
directories and/or frequently updated directories. For this,
one needs a protocol which transfers attribute level (or even
value-level) changes. Syncrel transfers entry-level changes.