We have a customer that has been multi-threading behind multiple servers and writing to our Master server. These writes come in the form of heavy spikes (1k over 5 second intervals) very much burst traffic and all the writes are adding new items to the same ou. While we have plans to throttle them I had a few questions:

a) If they're writing to the same ou / updating the same indexes are they blocked on one items success before another succeeds? So in this case multi threading behind multiple boxes does not give them any performance impact. I would guess this is the case, but I want to be sure. Because replication seems to be fine which goes through a single thread iirc.

b) are there any performance tweaks that can help? I thought maybe looking at nsslapd-threadnumber.

-Jeff