A question about indexing and performance measuring.
Under the _nodes/stats API, I see I have a stat called indices.indexing.index_time_in_millis. I am not sure how to interpret this number. (and others with time_in_milli suffix)
Lets say I have 4 CPU system.
If that number increases by 5000 in a 10 real (wall-clock) second interval, what's it telling me?
a) 1 of my CPUs was busy indexing for 5 seconds, and the others were idle
b) All of my CPUs were bust for 5 seconds, so each was busy for approx 1.25 seconds.
c) On average, 50% of the time the CPUs were bust doing indexing.
d) something else.
Put another way, can that difference in values of indices.indexing.index_time_in_millis be (at maximum) over a 10 real (wall-clock) second interval be 40 seconds on 4 CPU system? and therefore (theoretically) 80 seconds on an 8 CPU system?