Depends on many variables, for one how large is the network being monitored, how many elements are being monitored, and at what polling intervals? Any other modules to contend with? As the other posts you mentioned stated, large install can be very I/O intensive with the amount of read/writes on the DB, which may or may not degrade performance. Again, it depends on many things. The general recommendation is that of the
Orion DB Best Practices document mentioned above.Here are a couple of other docs about optimizing the SQL server that you may find helpful.