Keysight Technologies 3458A Guide D'utilisation page 444

D Optimizing Throughout and Reading Rate
The Product Note 3458A-2, High Resolution Digitizing with the 3458A System
Multimeter, covers the use of these commands in detail along with their
associated trigger commands and constraints. In general, the aspects of these
commands that most influence throughput are those associated with ACV, where
the 3458A handles the task of measuring the rms value of either repetitive wave
forms with the synchronous ACV or noise measurements with random ACV. A
detailed look at the techniques and the trade-offs of the three methods of rms
ACV measurement is in the next section.
444 Keysight 3458A User's Guide