問題文
The cluster-wide bandwidth measurement between nodes comes out below expectation. A team member suggests immediately adjusting the tuning variables of the collective library to see whether the figure improves. Why is that the wrong first move?
選択肢
- The tuning has to be applied identically on every node and the team has no way to do that yet, so the attempt would produce an inconsistent configuration.
- They only control how much logging the library produces and which subsystems it reports on during a run, so the tuning variables have no effect on the achieved bandwidth at all.
- The tuning is meant to be tried after the underlying system and fabric checks look healthy, so changing it first can mask a real fault or produce a figure that does not survive later.
- First, the measurement should be repeated more times, so that the spread between consecutive runs is known before any tuning variable is touched.